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android:onClick intent crashing app, throws IllegalStateException

I am very new to Android development and I am having an issue with an onClick function in my app. I have five buttons on one activity, and all of them are using the exact same code:
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Book 2"
android:layout_weight="1"
android:onClick="openBook2"/>
They're obviously adjusted according to the different java functions, which all look like this:
public void openBook2(View view) {
Intent i = new Intent(this, Real2.class);
startActivity(i);
}
The other four functions work perfectly, without error. For some reason, only this function causes a crash. Like I said, I'm new to this so I don't really understand what is going wrong here (or how to properly debug). I ran breakpoints on the openBook2 function and it came back with this in AppCompatViewInflater.java:
#Override
public void onClick(#NonNull View v) {
if (mResolvedMethod == null) {
resolveMethod(mHostView.getContext(), mMethodName);
}
try {
mResolvedMethod.invoke(mResolvedContext, v);
} catch (IllegalAccessException e) {
throw new IllegalStateException(
"Could not execute non-public method for android:onClick", e);
} catch (InvocationTargetException e) {
throw new IllegalStateException(
"Could not execute method for android:onClick", e);
}
}
I don't know what this means. I also know that I should be using a click listener because having the onClick directly in the xml is bad but I have tried to understand click listeners and I truly do not. And, the onClick has been working perfectly fine for me about a hundred other times in the app so I don't see a problem with it (especially since my app is only buttons and TextViews).
If you need any additional information, please let me know!
Logcat error:
2020-04-24 23:37:07.198 19688-19688/co.hyperstudios.elderscrollslibrary E/AndroidRuntime: FATAL EXCEPTION: main
Process: co.hyperstudios.elderscrollslibrary, PID: 19688
java.lang.RuntimeException: Unable to start activity ComponentInfo{co.hyperstudios.elderscrollslibrary/co.hyperstudios.elderscrollslibrary.Real2}: android.view.InflateException: Binary XML file line #75 in co.hyperstudios.elderscrollslibrary:layout/activity_real2: Binary XML file line #75 in co.hyperstudios.elderscrollslibrary:layout/activity_real2: Error inflating class TextView
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3270)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3409)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016)
at android.os.Handler.dispatchMessage(Handler.java:107)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7356)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
Caused by: android.view.InflateException: Binary XML file line #75 in co.hyperstudios.elderscrollslibrary:layout/activity_real2: Binary XML file line #75 in co.hyperstudios.elderscrollslibrary:layout/activity_real2: Error inflating class TextView
Caused by: android.view.InflateException: Binary XML file line #75 in co.hyperstudios.elderscrollslibrary:layout/activity_real2: Error inflating class TextView
Caused by: java.lang.IndexOutOfBoundsException: setSpan (5851 ... 5857) ends beyond length 16
at android.text.SpannableStringInternal.checkRange(SpannableStringInternal.java:490)
at android.text.SpannableStringInternal.setSpan(SpannableStringInternal.java:196)
at android.text.SpannableStringInternal.setSpan(SpannableStringInternal.java:183)
at android.text.SpannableString.setSpan(SpannableString.java:60)
at android.content.res.StringBlock.applyStyles(StringBlock.java:217)
at android.content.res.StringBlock.get(StringBlock.java:161)
at android.content.res.ApkAssets.getStringFromPool(ApkAssets.java:140)
at android.content.res.AssetManager.getPooledStringForCookie(AssetManager.java:787)
at android.content.res.TypedArray.loadStringValueAt(TypedArray.java:1375)
at android.content.res.TypedArray.getText(TypedArray.java:233)
at android.widget.TextView.<init>(TextView.java:1214)
at android.widget.TextView.<init>(TextView.java:968)
at androidx.appcompat.widget.AppCompatTextView.<init>(AppCompatTextView.java:99)
at androidx.appcompat.widget.AppCompatTextView.<init>(AppCompatTextView.java:95)
at androidx.appcompat.app.AppCompatViewInflater.createTextView(AppCompatViewInflater.java:182)
at androidx.appcompat.app.AppCompatViewInflater.createView(AppCompatViewInflater.java:103)
at androidx.appcompat.app.AppCompatDelegateImpl.createView(AppCompatDelegateImpl.java:1407)
at androidx.appcompat.app.AppCompatDelegateImpl.onCreateView(AppCompatDelegateImpl.java:1457)
at android.view.LayoutInflater.tryCreateView(LayoutInflater.java:1061)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:997)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:961)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:1123)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:1084)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:1126)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:1084)
at android.view.LayoutInflater.inflate(LayoutInflater.java:682)
at android.view.LayoutInflater.inflate(LayoutInflater.java:534)
at android.view.LayoutInflater.inflate(LayoutInflater.java:481)
2020-04-24 23:37:07.198 19688-19688/co.hyperstudios.elderscrollslibrary E/AndroidRuntime: at androidx.appcompat.app.AppCompatDelegateImpl.setContentView(AppCompatDelegateImpl.java:555)
at androidx.appcompat.app.AppCompatActivity.setContentView(AppCompatActivity.java:161)
at co.hyperstudios.elderscrollslibrary.Real2.onCreate(Real2.java:14)
at android.app.Activity.performCreate(Activity.java:7802)
at android.app.Activity.performCreate(Activity.java:7791)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1299)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3245)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3409)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016)
at android.os.Handler.dispatchMessage(Handler.java:107)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7356)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
activity_real2 TextView:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".Real2"
android:orientation="vertical">
<!--Title and author-->
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="20sp"
android:layout_marginTop="16dp"
android:textColor="#android:color/black"
android:text="The Real Barenziah"
android:layout_gravity="center" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="Plitinius Mero" />
<!--Buttons for different parts of the book-->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:paddingBottom="8dp"
android:paddingTop="8dp" >
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Book 1"
android:layout_weight="1"
android:onClick="openBook1"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Book 2"
android:layout_weight="1" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Book 3"
android:layout_weight="1"
android:onClick="openBook3"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Book 4"
android:layout_weight="1"
android:onClick="openBook4"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Book 5"
android:layout_weight="1"
android:onClick="openBook5"/>
</LinearLayout>
<!--Book text-->
<ScrollView
android:layout_width="wrap_content"
android:layout_height="match_parent" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/real2"
android:layout_marginStart="16dp"
android:layout_marginLeft="16dp"
android:paddingRight="16dp"
android:layout_gravity=""
android:textSize="15sp" />
</ScrollView>
</LinearLayout>

Yes, your problem is exactly the ScrollView. ScrollView doesn't work like that it has to have a layout on it to be used. so just add simply a layout on your ScrollView and put your TextView on that layout.
ScrollView > LinearLayout > TextView
(You can change LinearLayout to any ViewGroup type)just like this:
<ScrollView
android:layout_width="wrap_content"
android:layout_height="match_parent" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation:"vertical">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/real2"
android:layout_marginStart="16dp"
android:layout_marginLeft="16dp"
android:paddingRight="16dp"
android:layout_gravity=""
android:textSize="15sp" />
</LinearLayout>
</ScrollView>
Edit:
The Second problem and main problem of your code is probably the long String you had set for TextView just try to reduce the text.

How to fit a bitmap in a rounded square?

I'm using Android Studio and I would like to be able to pickup am image from the gallery, resize it and make it fit inside a rounded square (of about 300x300px) by maintening the correct aspect ratio.
At the moment, I'm able to resize it and display it as a circle.
FixBitmap = MediaStore.Images.Media.getBitmap(getContentResolver(), uri);
bitmap_to_save = scaleBitmapAndKeepRation(FixBitmap, 320, 320);
RoundedBitmapDrawable roundDrawable = RoundedBitmapDrawableFactory.create(getResources(), bitmap_to_save);
roundDrawable.setCircular(true);
p_avatar.setImageDrawable(roundDrawable);
However, I would like to know if it is possible to make the bitmap look like my attached image. Moreover, it would be important for me to resize the image without losing the original aspect ratio.
It is not exactly a well square rounded figure, so I'm not sure that it is possible to do it in Android.
Please, keep in mind that I dinamycally change the imageview inside the code depending on the user actions. So this is not a static image, I replace the original content with a new one if the user upload a new image.
EDIT 1 on May, 20
This is my XML code for the imageview "avatar":
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/ll_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="loginpackage.social.com.ui.profile.ProfileActivity">
<include layout="#layout/custom_toolbar_shadow" />
<ScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fillViewport="true">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center_horizontal"
android:orientation="vertical"
android:paddingTop="#dimen/_20sdp">
<ImageView
android:id="#+id/avatar"
android:layout_width="137dp"
android:layout_height="150dp"
android:layout_gravity="center"
android:clickable="true"
android:paddingBottom="#dimen/_10sdp"
android:paddingTop="#dimen/_10sdp"
/>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="#dimen/_20sdp"
android:orientation="vertical"
android:paddingLeft="#dimen/_16sdp"
android:paddingRight="#dimen/_16sdp">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/profileActivity_name"
android:textSize="#dimen/_14sdp" />
<EditText
android:id="#+id/et_fullname"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="#dimen/_5sdp"
android:background="#color/colorWhite"
android:hint="#string/signActivity_fullname"
android:imeOptions="actionDone"
android:inputType="textNoSuggestions"
android:maxLines="1"
android:padding="#dimen/_10sdp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="#dimen/_10sdp"
android:text="#string/profileActivity_email"
android:textSize="#dimen/_14sdp" />
<EditText
android:id="#+id/et_email"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="#dimen/_5sdp"
android:background="#drawable/editext_back_login"
android:hint="#string/mainActivity_email"
android:imeOptions="actionNext"
android:inputType="textEmailAddress|textNoSuggestions"
android:maxLines="1"
android:padding="#dimen/_10sdp" />
<Button
android:id="#+id/btn_update"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="#dimen/_20sdp"
android:background="#color/colorSignuoBtn"
android:text="#string/profileActivity_update"
android:textColor="#color/colorWhite"
android:textSize="#dimen/_12sdp"
android:visibility="invisible" />
<TextView
android:id="#+id/txt_logout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginBottom="#dimen/_10sdp"
android:layout_marginTop="#dimen/_20sdp"
android:background="#drawable/button_logout_profile"
android:foreground="?attr/selectableItemBackgroundBorderless"
android:gravity="center"
android:paddingBottom="#dimen/_12sdp"
android:paddingTop="#dimen/_12sdp"
android:text="#string/profileActivity_logout"
android:textSize="#dimen/_12sdp" />
</LinearLayout>
</LinearLayout>
</ScrollView>
</LinearLayout>
EDIT 2
At the moment, I'm using Picasso to round the image and it seems to work well.
The problem is that I would like to keep always the same picture size (350x350px) and the aspect ratio. How is it possible to do it?
Transformation transformation = new RoundedTransformationBuilder()
.borderColor(Color.GREEN)
.borderWidthDp(2)
.cornerRadiusDp(15)
.oval(false)
.build();
Picasso.get().load("http://www.server.com/uploads/avatars/"+Conts.USERINFO.getId()).transform(transformation).memoryPolicy(MemoryPolicy.NO_CACHE, MemoryPolicy.NO_STORE).networkPolicy(NetworkPolicy.NO_CACHE) .into(p_avatar);
EDIT3:
<com.makeramen.roundedimageview.RoundedImageView
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/avatar"
android:layout_width="160dp"
android:layout_height="160dp"
android:src="#drawable/adduserprofile"
android:scaleType="centerCrop"
app:riv_border_width="2dip"
app:riv_border_color="#333333"
app:riv_mutate_background="true"
app:riv_oval="false"
app:riv_corner_radius_bottom_left="20dp"
app:riv_corner_radius_top_right="20dp"
/>
Why if I set a different value for riv_corner_radius_top_right, then the app crashes?
For example, if I set:
app:riv_corner_radius_bottom_left="20dp"
app:riv_corner_radius_top_right="10dp"
I get this error:
E/AndroidRuntime: FATAL EXCEPTION: main
Process: loginpackage.social.com, PID: 25495
java.lang.RuntimeException: Unable to start activity ComponentInfo{loginpackage.social.com/loginpackage.social.com.ui.profile.ProfileActivity}: android.view.InflateException: Binary XML file line #24: Error inflating class com.makeramen.roundedimageview.RoundedImageView
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2689)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2754)
at android.app.ActivityThread.access$900(ActivityThread.java:177)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1448)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:5938)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1400)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1195)
Caused by: android.view.InflateException: Binary XML file line #24: Error inflating class com.makeramen.roundedimageview.RoundedImageView
at android.view.LayoutInflater.createView(LayoutInflater.java:640)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:750)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:813)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:821)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:821)
at android.view.LayoutInflater.inflate(LayoutInflater.java:511)
at android.view.LayoutInflater.inflate(LayoutInflater.java:415)
at android.view.LayoutInflater.inflate(LayoutInflater.java:366)
at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:287)
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:139)
at loginpackage.social.com.ui.profile.ProfileActivity.onCreate(ProfileActivity.java:93)
at android.app.Activity.performCreate(Activity.java:6288)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2642)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2754) 
at android.app.ActivityThread.access$900(ActivityThread.java:177) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1448) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:145) 
at android.app.ActivityThread.main(ActivityThread.java:5938) 
at java.lang.reflect.Method.invoke(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:372) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1400) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1195) 
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Constructor.newInstance(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:288)
at android.view.LayoutInflater.createView(LayoutInflater.java:614)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:750) 
at android.view.LayoutInflater.rInflate(LayoutInflater.java:813) 
at android.view.LayoutInflater.rInflate(LayoutInflater.java:821) 
at android.view.LayoutInflater.rInflate(LayoutInflater.java:821) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:511) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:415) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:366) 
at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:287) 
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:139) 
at loginpackage.social.com.ui.profile.ProfileActivity.onCreate(ProfileActivity.java:93) 
at android.app.Activity.performCreate(Activity.java:6288) 
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119) 
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2642) 
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2754) 
at android.app.ActivityThread.access$900(ActivityThread.java:177) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1448) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:145) 
at android.app.ActivityThread.main(ActivityThread.java:5938) 
at java.lang.reflect.Method.invoke(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:372) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1400) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1195) 
Caused by: java.lang.IllegalArgumentException: Multiple nonzero corner radii not yet supported.
at com.makeramen.roundedimageview.RoundedDrawable.setCornerRadius(RoundedDrawable.java:507)
at com.makeramen.roundedimageview.RoundedImageView.updateAttrs(RoundedImageView.java:368)
at com.makeramen.roundedimageview.RoundedImageView.updateDrawableAttrs(RoundedImageView.java:318)
at com.makeramen.roundedimageview.RoundedImageView.<init>(RoundedImageView.java:163)
at com.makeramen.roundedimageview.RoundedImageView.<init>(RoundedImageView.java:86)
at java.lang.reflect.Constructor.newInstance(Native Method) 
at java.lang.reflect.Constructor.newInstance(Constructor.java:288) 
at android.view.LayoutInflater.createView(LayoutInflater.java:614) 
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:750) 
at android.view.LayoutInflater.rInflate(LayoutInflater.java:813) 
at android.view.LayoutInflater.rInflate(LayoutInflater.java:821) 
at android.view.LayoutInflater.rInflate(LayoutInflater.java:821) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:511) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:415) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:366) 
at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:287) 
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:139) 
at loginpackage.social.com.ui.profile.ProfileActivity.onCreate(ProfileActivity.java:93) 
at android.app.Activity.performCreate(Activity.java:6288) 
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119) 
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2642) 
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2754) 
at android.app.ActivityThread.access$900(ActivityThread.java:177) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1448) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:145) 
at android.app.ActivityThread.main(ActivityThread.java:5938) 
at java.lang.reflect.Method.invoke(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:372) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1400) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1195) 

You should not give your time to manage these types of logics if you are working on projects in company.
Instead you can just use libraries which have already done great work.
See https://github.com/vinc3m1/RoundedImageView
Your ImageView will be like
<com.makeramen.roundedimageview.RoundedImageView
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/imageView1"
android:src="#drawable/photo1"
android:scaleType="centerCrop"
app:riv_corner_radius="30dip"
app:riv_border_width="2dip"
app:riv_border_color="#333333"
app:riv_mutate_background="true"
app:riv_tile_mode="repeat"
app:riv_oval="true" />
and dependency
repositories {
mavenCentral()
}
dependencies {
compile 'com.makeramen:roundedimageview:2.3.0'
}
Update
You seem new to android, if you don't understand id and src, no worries!
Basically id is an unique id that you have created and you refer to
imageView1 if you do findViewById(R.id.imageView1) in your java code.
for more info about id : Difference between "#id/" and "#+id/" in Android
src is the source image file for that image, that is located in your drawables directory.
About your issue
You can use different ImageView ScaleType that matches your requirement.
I think you use android:scaleType="centerCrop" that fit your image at imageView.
I also edited scaleType in above answer. If that does not fit your requirement you can use any of these scale type
Update 2 for setting width and height, you can set layout_width and layout_height attribute. like below.
<com.makeramen.roundedimageview.RoundedImageView
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/imageView1"
android:src="#drawable/photo1"
android:scaleType="centerCrop"
app:riv_corner_radius="30dip"
app:riv_border_width="2dip"
app:riv_border_color="#333333"
app:riv_mutate_background="true"
app:riv_tile_mode="repeat"
app:riv_oval="true"
android:layout_width="350dp"
android:layout_height="350dp"/>
see What is the difference between "px", "dip", "dp" and "sp"? for more detail about sp, dp, px in android.

I wrote a MaskView that lets you mask images to any shape, including holes in the middle and partial transparency. It's a lot of code, and I wrote it a long time ago so I wouldn't even use it myself without reviewing it. But the essence of it is an ImageView that takes an alpha mask. When it draws itself, it draws two bitmaps for itself and whatever is behind it, and combines them using the mask.

My app is not working on Marshmallow and below but min sdk is 21. How to resolve?

Click here for gradebuild app file
Min SDK screenshot details:Minsdk is set to 21 & TargetSDK is set to 27
I am a beginner in Android Studio and this is my first app.
Click here for Logcat: Logcat
This is the activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:background="#ffffff"
tools:context=".MainActivity"
tools:layout_editor_absoluteY="25dp"
tools:layout_width="match_parent">
<ImageButton
android:id="#+id/cgpa"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true"
android:layout_marginStart="16dp"
android:layout_marginTop="16dp"
android:background="#ffffff"
android:onClick="clickcgpa"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:srcCompat="#drawable/cal"
android:contentDescription="#string/todo4" />
<ImageButton
android:id="#+id/cal"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentStart="true"
android:background="#ffffff"
android:onClick="clickcal"
app:layout_constraintEnd_toStartOf="#+id/club"
app:layout_constraintStart_toEndOf="#+id/map"
app:layout_constraintTop_toTopOf="#+id/club"
app:srcCompat="#drawable/calender"
android:contentDescription="#string/todo3" />
<ImageButton
android:id="#+id/map"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_alignTop="#+id/cgpa"
android:layout_marginStart="3dp"
android:background="#ffffff"
android:onClick="clickmap"
app:layout_constraintEnd_toStartOf="#+id/calendar"
app:layout_constraintHorizontal_chainStyle="packed"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="#+id/calendar"
app:srcCompat="#drawable/marker"
android:contentDescription="#string/todo1" />
<TextView
android:id="#+id/textView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_below="#+id/cgpa"
android:layout_marginEnd="9dp"
android:text="#string/cgpa_calculator"
android:textAlignment="center"
android:textStyle="bold"
app:layout_constraintEnd_toEndOf="#+id/cgpa"
app:layout_constraintTop_toBottomOf="#+id/cgpa" />
<TextView
android:id="#+id/textView5"
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginStart="16dp"
android:text="#string/campus_map"
android:textAlignment="center"
android:textStyle="bold"
app:layout_constraintBottom_toBottomOf="#+id/textView6"
app:layout_constraintStart_toStartOf="#+id/map"
app:layout_constraintTop_toBottomOf="#+id/map" />
<TextView
android:id="#+id/textView6"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_alignParentTop="true"
android:layout_marginEnd="33dp"
android:gravity="center_vertical"
android:text="#string/Main"
android:textAlignment="center"
android:textStyle="bold"
app:layout_constraintEnd_toEndOf="#+id/calendar"
app:layout_constraintTop_toBottomOf="#+id/calendar" />
<TextView
android:id="#+id/textView7"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="18dp"
android:fontFamily="monospace"
android:text="#string/coming_soon"
android:textAppearance="#style/TextAppearance.AppCompat.Body2"
android:textColor="#777777"
android:textSize="24sp"
android:textStyle="bold"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/textView4" />
<ImageButton
android:id="#+id/club"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="234dp"
android:background="#ffffff"
android:onClick="clickclub"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="#+id/calendar"
app:layout_constraintTop_toTopOf="parent"
app:srcCompat="#drawable/people2"
android:contentDescription="#string/todo2" />
<TextView
android:id="#+id/textView8"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/club"
android:textAlignment="center"
android:textStyle="bold"
app:layout_constraintEnd_toEndOf="#+id/club"
app:layout_constraintStart_toStartOf="#+id/club"
app:layout_constraintTop_toBottomOf="#+id/club" />
</android.support.constraint.ConstraintLayout>
This is activity_welcome.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#000000"
tools:context=".Welcome">
<ImageView
android:id="#+id/imageView5"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="8dp"
android:layout_marginRight="8dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:srcCompat="#drawable/logomain" />
</android.support.constraint.ConstraintLayout>
And Manifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.workingbros.ak.assist" android:versionCode="2">
<application
android:icon="#drawable/logomain1"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity android:name=".CGPA"></activity>
<activity android:name=".MainActivity">
</activity>
<activity android:name=".Welcome">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
Stack Trace:
04-12 23:25:46.153 30277-30277/com.workingbros.ak.assist E/Minikin: addFont failed to create font /system/fonts/NanumGothic.ttf
addFont failed to create font /system/fonts/DroidSansFallback.ttf
04-12 23:25:46.154 30277-30277/com.workingbros.ak.assist E/Minikin: addFont failed to create font /system/fonts/MTLmr3m.ttf
04-12 23:25:46.364 30277-30277/com.workingbros.ak.assist E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.workingbros.ak.assist, PID: 30277
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.workingbros.ak.assist/com.workingbros.ak.assist.MainActivity}: android.view.InflateException: Binary XML file line #13: Binary XML file line #13: Error inflating class ImageButton
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2560)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2626)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1475)
at android.os.Handler.dispatchMessage(Handler.java:111)
at android.os.Looper.loop(Looper.java:207)
at android.app.ActivityThread.main(ActivityThread.java:5740)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:905)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:766)
Caused by: android.view.InflateException: Binary XML file line #13: Binary XML file line #13: Error inflating class ImageButton
at android.view.LayoutInflater.inflate(LayoutInflater.java:539)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
at android.view.LayoutInflater.inflate(LayoutInflater.java:374)
at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:287)
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:139)
at com.workingbros.ak.assist.MainActivity.onCreate(MainActivity.java:15)
at android.app.Activity.performCreate(Activity.java:6543)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1113)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2513)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2626) 
at android.app.ActivityThread.-wrap11(ActivityThread.java) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1475) 
at android.os.Handler.dispatchMessage(Handler.java:111) 
at android.os.Looper.loop(Looper.java:207) 
at android.app.ActivityThread.main(ActivityThread.java:5740) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:905) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:766) 
Caused by: android.view.InflateException: Binary XML file line #13: Error inflating class ImageButton
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:782)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:704)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:835)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798)
at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:374) 
at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:287) 
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:139) 
at com.workingbros.ak.assist.MainActivity.onCreate(MainActivity.java:15) 
at android.app.Activity.performCreate(Activity.java:6543) 
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1113) 
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2513) 
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2626) 
at android.app.ActivityThread.-wrap11(ActivityThread.java) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1475) 
at android.os.Handler.dispatchMessage(Handler.java:111) 
at android.os.Looper.loop(Looper.java:207) 
at android.app.ActivityThread.main(ActivityThread.java:5740) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:905) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:766) 
Caused by: android.content.res.Resources$NotFoundException: Resource ID #0x7f070054
at android.content.res.Resources.getValue(Resources.java:1552)
at android.support.v7.widget.AppCompatDrawableManager.loadDrawableFromDelegates(AppCompatDrawableManager.java:328)
at android.support.v7.widget.AppCompatDrawableManager.getDrawable(AppCompatDrawableManager.java:193)
at android.support.v7.widget.AppCompatDrawableManager.getDrawable(AppCompatDrawableManager.java:186)
at android.support.v7.content.res.AppCompatResources.getDrawable(AppCompatResources.java:100)
at android.support.v7.widget.AppCompatImageHelper.loadFromAttributes(AppCompatImageHelper.java:58)
at android.support.v7.widget.AppCompatImageButton.<init>(AppCompatImageButton.java:78)
at android.support.v7.widget.AppCompatImageButton.<init>(AppCompatImageButton.java:68)
at android.support.v7.app.AppCompatViewInflater.createImageButton(AppCompatViewInflater.java:201)
at android.support.v7.app.AppCompatViewInflater.createView(AppCompatViewInflater.java:121)
at android.support.v7.app.AppCompatDelegateImplV9.createView(AppCompatDelegateImplV9.java:1035)
at android.support.v7.app.AppCompatDelegateImplV9.onCreateView(AppCompatDelegateImplV9.java:1092)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:746)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:704) 
at android.view.LayoutInflater.rInflate(LayoutInflater.java:835) 
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:515) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:423) 
at android.view.LayoutInflater.inflate(LayoutInflater.java:374) 
at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:287) 
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:139) 
at com.workingbros.ak.assist.MainActivity.onCreate(MainActivity.java:15) 
at android.app.Activity.performCreate(Activity.java:6543) 
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1113) 
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2513) 
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2626) 
at android.app.ActivityThread.-wrap11(ActivityThread.java) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1475) 
at android.os.Handler.dispatchMessage(Handler.java:111) 
at android.os.Looper.loop(Looper.java:207) 
at android.app.ActivityThread.main(ActivityThread.java:5740) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:905) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:766) 
MainActivity.java
package com.workingbros.ak.assist;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageButton;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
ImageButton cgpa,cal,map,club;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
cgpa= findViewById(R.id.cgpa);
map=findViewById(R.id.map);
club=findViewById(R.id.club);
cal=findViewById(R.id.cal);
}
public void clickcgpa(View v){
Intent main=new Intent(MainActivity.this,CGPA.class);
startActivity(main);
}
public void clickmap(View v)
{
Toast.makeText(this,"Coming Soon",Toast.LENGTH_SHORT).show();
}
public void clickclub(View v)
{
Toast.makeText(this,"Coming Soon",Toast.LENGTH_SHORT).show();
}
public void clickcal(View v)
{
Toast.makeText(this,"Coming Soon",Toast.LENGTH_SHORT).show();
}
}
Welcome.java
package com.workingbros.ak.assist;
import android.content.Intent;
import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Window;
import android.view.WindowManager;
public class Welcome extends AppCompatActivity {
private static int SPLASH_TIME_OUT=1000;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_welcome);
new Handler().postDelayed(new Runnable(){
#Override
public void run(){
Intent homeIntent=new Intent(Welcome.this,MainActivity.class);
startActivity(homeIntent);
finish();
}
},SPLASH_TIME_OUT);
}
}
please tell me where is the error?
Compilation error after applying fix:
org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':app:compileDebugJavaWithJavac'.
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:100)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:70)
at org.gradle.api.internal.tasks.execution.OutputDirectoryCreatingTaskExecuter.execute(OutputDirectoryCreatingTaskExecuter.java:51)
at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:62)
at org.gradle.api.internal.tasks.execution.ResolveTaskOutputCachingStateExecuter.execute(ResolveTaskOutputCachingStateExecuter.java:54)
at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:60)
at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:97)
at org.gradle.api.internal.tasks.execution.CleanupStaleOutputsExecuter.execute(CleanupStaleOutputsExecuter.java:87)
at org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter.execute(ResolveTaskArtifactStateTaskExecuter.java:52)
at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:52)
at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:54)
at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:34)
at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker$1.run(DefaultTaskGraphExecuter.java:248)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:241)
at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:230)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.processTask(DefaultTaskPlanExecutor.java:123)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.access$200(DefaultTaskPlanExecutor.java:79)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:104)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:98)
at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.execute(DefaultTaskExecutionPlan.java:626)
at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.executeWithTask(DefaultTaskExecutionPlan.java:581)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.run(DefaultTaskPlanExecutor.java:98)
at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.gradle.api.internal.tasks.compile.CompilationFailedException: Compilation failed; see the compiler error output for details.
at org.gradle.api.internal.tasks.compile.JdkJavaCompiler.execute(JdkJavaCompiler.java:50)
at org.gradle.api.internal.tasks.compile.JdkJavaCompiler.execute(JdkJavaCompiler.java:35)
at org.gradle.api.internal.tasks.compile.NormalizingJavaCompiler.delegateAndHandleErrors(NormalizingJavaCompiler.java:98)
at org.gradle.api.internal.tasks.compile.NormalizingJavaCompiler.execute(NormalizingJavaCompiler.java:51)
at org.gradle.api.internal.tasks.compile.NormalizingJavaCompiler.execute(NormalizingJavaCompiler.java:37)
at org.gradle.api.internal.tasks.compile.CleaningJavaCompilerSupport.execute(CleaningJavaCompilerSupport.java:35)
at org.gradle.api.internal.tasks.compile.CleaningJavaCompilerSupport.execute(CleaningJavaCompilerSupport.java:25)
at org.gradle.api.internal.tasks.compile.incremental.IncrementalCompilationFinalizer.execute(IncrementalCompilationFinalizer.java:39)
at org.gradle.api.internal.tasks.compile.incremental.IncrementalCompilationFinalizer.execute(IncrementalCompilationFinalizer.java:24)
at org.gradle.api.tasks.compile.JavaCompile.performCompilation(JavaCompile.java:207)
at org.gradle.api.tasks.compile.JavaCompile.compile(JavaCompile.java:133)
at com.android.build.gradle.tasks.factory.AndroidJavaCompile.compile(AndroidJavaCompile.java:125)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:73)
at org.gradle.api.internal.project.taskfactory.IncrementalTaskAction.doExecute(IncrementalTaskAction.java:46)
at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:39)
at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:26)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$1.run(ExecuteActionsTaskExecuter.java:121)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:110)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:92)
... 32 more

You have given constraints to map Imagebutton, textView6 TextView and club ImageButton with respect to calender id but as i can see in your activity_main.xml file there is no view having calender id. May be you have it earlier but after that you have changed it to cal id. so, you have to refer your view constraints with respect to cal instead of calender id. Because of wrong id you are getting inflating error.
I have modified your activity_main.xml as below. you can just copy and paste it in your code.
edited activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:background="#ffffff"
tools:context=".MainActivity"
tools:layout_editor_absoluteY="25dp"
tools:layout_width="match_parent">
<ImageButton
android:id="#+id/cgpa"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true"
android:layout_marginStart="16dp"
android:layout_marginTop="16dp"
android:background="#ffffff"
android:onClick="clickcgpa"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:srcCompat="#drawable/cal"
android:contentDescription="#string/todo4" />
<ImageButton
android:id="#+id/cal"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentStart="true"
android:background="#ffffff"
android:onClick="clickcal"
app:layout_constraintEnd_toStartOf="#+id/club"
app:layout_constraintStart_toEndOf="#+id/map"
app:layout_constraintTop_toTopOf="#+id/club"
app:srcCompat="#drawable/calender"
android:contentDescription="#string/todo3" />
<ImageButton
android:id="#+id/map"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_alignTop="#+id/cgpa"
android:layout_marginStart="3dp"
android:background="#ffffff"
android:onClick="clickmap"
app:layout_constraintEnd_toStartOf="#+id/cal"
app:layout_constraintHorizontal_chainStyle="packed"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="#+id/cal"
app:srcCompat="#drawable/marker"
android:contentDescription="#string/todo1" />
<TextView
android:id="#+id/textView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_below="#+id/cgpa"
android:layout_marginEnd="9dp"
android:text="#string/cgpa_calculator"
android:textAlignment="center"
android:textStyle="bold"
app:layout_constraintEnd_toEndOf="#+id/cgpa"
app:layout_constraintTop_toBottomOf="#+id/cgpa" />
<TextView
android:id="#+id/textView5"
android:layout_width="wrap_content"
android:layout_height="0dp"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginStart="16dp"
android:text="#string/campus_map"
android:textAlignment="center"
android:textStyle="bold"
app:layout_constraintBottom_toBottomOf="#+id/textView6"
app:layout_constraintStart_toStartOf="#+id/map"
app:layout_constraintTop_toBottomOf="#+id/map" />
<TextView
android:id="#+id/textView6"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_alignParentTop="true"
android:layout_marginEnd="33dp"
android:gravity="center_vertical"
android:text="#string/Main"
android:textAlignment="center"
android:textStyle="bold"
app:layout_constraintEnd_toEndOf="#+id/cal"
app:layout_constraintTop_toBottomOf="#+id/cal" />
<TextView
android:id="#+id/textView7"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="18dp"
android:fontFamily="monospace"
android:text="#string/coming_soon"
android:textAppearance="#style/TextAppearance.AppCompat.Body2"
android:textColor="#777777"
android:textSize="24sp"
android:textStyle="bold"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/textView4" />
<ImageButton
android:id="#+id/club"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="234dp"
android:background="#ffffff"
android:onClick="clickclub"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="#+id/cal"
app:layout_constraintTop_toTopOf="parent"
app:srcCompat="#drawable/people2"
android:contentDescription="#string/todo2" />
<TextView
android:id="#+id/textView8"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/club"
android:textAlignment="center"
android:textStyle="bold"
app:layout_constraintEnd_toEndOf="#+id/club"
app:layout_constraintStart_toStartOf="#+id/club"
app:layout_constraintTop_toBottomOf="#+id/club" />
</android.support.constraint.ConstraintLayout>
And in future if you want to change any views id then i suggest you to change it from design section because it will ask you a option to change id at all places where you have used it. So, you don't need to update it manually at every place.
UPDATE
As i can see in your project code(Received in private chat) there is some images only in drawable-v24. So, this images are only comfortable with some versions as said here. So, you have to put your images in drawable folder also to make compatible your app in all the versions.
As i can see there is two images cal.png and people2.png in only drawable-v24 and not in drawable folder. so, simple copy and paste them into drawable folder and all will be ok. You can run your project on every devices having versions between your minsdk and targetsdk version.

Unfortunately, App has stopped on physical device when making changes to .xml in layout-land file in Android [duplicate]

This question already has answers here:
What is a NullPointerException, and how do I fix it?
(12 answers)
Closed 6 years ago.
In chapter 3 of Big Nerd Ranch guide, they explain how to differently layout the default and landscape views. But when I create an Android Resource Directory with Landscape orientation and then copy the same .xml from the default layout into the /layout-land and make changes into the latter, the app crashes on my physical device when I rotate to landscape mode.
If I don't change anything in the copied .xml inside the /layout-land file, it runs absolutely fine when rotated.
activity.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:orientation="vertical"
>
<TextView
android:id="#+id/question_text_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="24dp" />
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal">
<Button
android:id="#+id/true_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/true_button"/>
<Button
android:id="#+id/false_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/false_button"/>
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
>
<Button
android:id="#+id/prev_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/prev_button"/>
<Button
android:id="#+id/next_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/next_button"/>
</LinearLayout>
</LinearLayout>
/layout-land/activity.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:orientation="vertical"
>
<TextView
android:id="#+id/question_text_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="24dp" />
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal">
<Button
android:id="#+id/true_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/true_button"/>
<Button
android:id="#+id/false_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/false_button"/>
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
>
<Button
android:id="#+id/prev_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/prev_button"/>
</LinearLayout>
</LinearLayout>
Logcat
FATAL EXCEPTION: main
Process: com.bignerdranch.android.geoquiz, PID: 5727
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.bignerdranch.android.geoquiz/com.bignerdranch.android.geoquiz.QuizActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2695)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2769)
at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:4378)
at android.app.ActivityThread.access$1000(ActivityThread.java:177)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1436)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5910)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1405)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1200)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
at com.bignerdranch.android.geoquiz.QuizActivity.onCreate(QuizActivity.java:81)
at android.app.Activity.performCreate(Activity.java:6178)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2648)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2769) 
at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:4378) 
at android.app.ActivityThread.access$1000(ActivityThread.java:177) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1436) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:135) 
at android.app.ActivityThread.main(ActivityThread.java:5910) 
at java.lang.reflect.Method.invoke(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:372)
Cannot figure out what is the problem. Please help

You can have different layout files that appear different, but if you are using findViewById on views that do not exist (such as the next button), then you'll get a NullPointerException when you go to call any methods on that view (such as assign it's click listener, in the case of your error).
The simple solution is to keep all the views in both layouts with the same ids, but just rearrange them according to the orientation.

NPE while inflating layout (Attempt to invoke virtual method 'boolean java.lang.String.equals(java.lang.Object)' on a null object reference)

I keep getting a java.lang.NullPointerException when I try to use ScrollView in an activity.
The weird thing is that I've used the exact same Scrollview setup in other activities. And all of a sudden I'm getting errors. I've tried cleaning the project and rebuilding.
And I've tried the good old restart the program. I learned a lot about Null Pointer Exceptions today, but I haven't been able to figure out why I keep getting Rendering Problems.
This is the java.lang.NullPointerException that is thrown on the XML:
java.lang.NullPointerException
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:738)
at android.view.BridgeInflater.createViewFromTag(BridgeInflater.java:149)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:704)
at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:835)
at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:70)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:811)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798)
at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:838)
at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:70)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:811)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798)
at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:838)
at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:70)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:811)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798)
at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
at android.view.LayoutInflater.inflate(LayoutInflater.java:394)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.inflate(RenderSessionImpl.java:223)
at com.android.layoutlib.bridge.Bridge.createSession(Bridge.java:426)
at com.android.ide.common.rendering.LayoutLibrary.createSession(LayoutLibrary.java:350)
at com.android.tools.idea.rendering.RenderTask$2.compute(RenderTask.java:510)
at com.android.tools.idea.rendering.RenderTask$2.compute(RenderTask.java:498)
at com.intellij.openapi.application.impl.ApplicationImpl.runReadAction(ApplicationImpl.java:888)
at com.android.tools.idea.rendering.RenderTask.createRenderSession(RenderTask.java:498)
at com.android.tools.idea.rendering.RenderTask.access$600(RenderTask.java:72)
at com.android.tools.idea.rendering.RenderTask$3.call(RenderTask.java:610)
at com.android.tools.idea.rendering.RenderTask$3.call(RenderTask.java:607)
at com.android.tools.idea.rendering.RenderService.runRenderAction(RenderService.java:362)
at com.android.tools.idea.rendering.RenderTask.render(RenderTask.java:607)
at com.android.tools.idea.rendering.RenderTask.render(RenderTask.java:629)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager.doRender(AndroidLayoutPreviewToolWindowManager.java:652)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager.access$1700(AndroidLayoutPreviewToolWindowManager.java:80)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager$7$1.run(AndroidLayoutPreviewToolWindowManager.java:594)
at com.intellij.openapi.progress.impl.CoreProgressManager$2.run(CoreProgressManager.java:152)
at com.intellij.openapi.progress.impl.CoreProgressManager.registerIndicatorAndRun(CoreProgressManager.java:452)
at com.intellij.openapi.progress.impl.CoreProgressManager.executeProcessUnderProgress(CoreProgressManager.java:402)
at com.intellij.openapi.progress.impl.ProgressManagerImpl.executeProcessUnderProgress(ProgressManagerImpl.java:54)
at com.intellij.openapi.progress.impl.CoreProgressManager.runProcess(CoreProgressManager.java:137)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager$7.run(AndroidLayoutPreviewToolWindowManager.java:589)
at com.intellij.util.ui.update.MergingUpdateQueue.execute(MergingUpdateQueue.java:320)
at com.intellij.util.ui.update.MergingUpdateQueue.execute(MergingUpdateQueue.java:310)
at com.intellij.util.ui.update.MergingUpdateQueue$2.run(MergingUpdateQueue.java:254)
at com.intellij.util.ui.update.MergingUpdateQueue.flush(MergingUpdateQueue.java:269)
at com.intellij.util.ui.update.MergingUpdateQueue.flush(MergingUpdateQueue.java:227)
at com.intellij.util.ui.update.MergingUpdateQueue.run(MergingUpdateQueue.java:217)
at com.intellij.util.concurrency.QueueProcessor.runSafely(QueueProcessor.java:238)
at com.intellij.util.Alarm$Request$1.run(Alarm.java:351)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
So, none of this is code that I wrote. So I dove into the stack trace and found this:
java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.lang.String.equals(java.lang.Object)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2325)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387)
at android.app.ActivityThread.access$800(ActivityThread.java:151)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5254)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.lang.String.equals(java.lang.Object)' on a null object reference
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:715)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:806)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:809)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:809)
at android.view.LayoutInflater.inflate(LayoutInflater.java:504)
at android.view.LayoutInflater.inflate(LayoutInflater.java:414)
at android.view.LayoutInflater.inflate(LayoutInflater.java:365)
at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:378)
at android.app.Activity.setContentView(Activity.java:2145)
at com.mitchellpalermo.tutroubleshooting.ContactPage.onCreate(ContactPage.java:11)
at android.app.Activity.performCreate(Activity.java:5990)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2278)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387) 
at android.app.ActivityThread.access$800(ActivityThread.java:151) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:135) 
at android.app.ActivityThread.main(ActivityThread.java:5254) 
at java.lang.reflect.Method.invoke(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:372) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
Which points to line 11 on the Contact.java file. Which looks like this (I've put indicators around line 11) :
package com.mitchellpalermo.tutroubleshooting;
import android.app.Activity;
import android.os.Bundle;
public class Contact extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_contact); // line 11
}
}
I don't see a problem with line 11.
Now, I can't figure out what is wrong with my code. Between Rendering Problems and NullPointerExceptions, I can't figure out what is actually wrong with my code.
This is an example of XML in an activity in which the ScrollView doesn't throw any errors:
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
tools:context="com.mitchellpalermo.tutroubleshooting.ComputerOrProjector">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:orientation="vertical">
<TextView
style="#style/HeaderStyle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="#string/solutions"
android:textStyle="bold" />
<!-- A CardView that contains a TextView -->
<android.support.v7.widget.CardView xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_margin="15dp"
card_view:cardBackgroundColor="#FFFFFF"
card_view:cardCornerRadius="4dp"
card_view:cardElevation="5dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
style="#style/Solution"
android:text="#string/pc_v_fifth" />
<View
android:layout_width="match_parent"
android:layout_height="2dp"
android:background="#android:color/darker_gray" />
<TextView
style="#style/Solution"
android:text="#string/pc_v_first" />
<View
android:layout_width="match_parent"
android:layout_height="2dp"
android:background="#android:color/darker_gray" />
<TextView
style="#style/Solution"
android:text="#string/pc_v_second" />
<View
android:layout_width="match_parent"
android:layout_height="2dp"
android:background="#android:color/darker_gray" />
<TextView
style="#style/Solution"
android:text="#string/pc_v_third" />
<View
android:layout_width="match_parent"
android:layout_height="2dp"
android:background="#android:color/darker_gray" />
<TextView
style="#style/Solution"
android:text="#string/pc_v_fourth" />
<View
android:layout_width="match_parent"
android:layout_height="2dp"
android:background="#android:color/darker_gray" />
</LinearLayout>
</android.support.v7.widget.CardView>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<Button
style="#style/NextButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:onClick="sendEmail"
android:text="#string/fixed"
android:textStyle="bold" />
<Button
style="#style/NextButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:onClick="notFixedButton"
android:text="#string/not_fixed"
android:textStyle="bold" />
</LinearLayout>
</LinearLayout>
</ScrollView>
And here is the activity in which I receive errors:
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:fillViewport="false">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
style="#style/HeaderStyle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="#string/still_not_fixed" />
<!-- A CardView that contains a TextView -->
<android.support.v7.widget.CardView xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_margin="15dp"
card_view:cardBackgroundColor="#FFFFFF"
card_view:cardCornerRadius="4dp"
card_view:cardElevation="5dp">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/hector" />
<view
android:layout_width="match_parent"
android:layout_height="2dp"
android:backgroundTint="#android:color/darker_gray" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/robert" />
<view
android:layout_width="match_parent"
android:layout_height="2dp"
android:backgroundTint="#android:color/darker_gray" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/mitch" />
</android.support.v7.widget.CardView>
</LinearLayout>
</ScrollView>
Any suggestions? And thank you so much in advance!

Change <view to <View, because view is not about empty view. It's for custom view defined through class attr, like below:
<view
android:layout_width="wrap_content"
android:layout_height="wrap_content"
class="com.your.package.YourCustomView" />
And you got
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.lang.String.equals(java.lang.Object)' on a null object reference
because of LayoutInflater tries to parse class attr:
LayoutInflater source code
//...
View createViewFromTag(View parent, String name, Context context, AttributeSet attrs,
boolean ignoreThemeAttr) {
if (name.equals("view")) { // line 724
name = attrs.getAttributeValue(null, "class"); // line 725
}
// Apply a theme wrapper, if allowed and one is specified.
if (!ignoreThemeAttr) {
final TypedArray ta = context.obtainStyledAttributes(attrs, ATTRS_THEME);
final int themeResId = ta.getResourceId(0, 0);
if (themeResId != 0) {
context = new ContextThemeWrapper(context, themeResId);
}
ta.recycle();
}
if (name.equals(TAG_1995)) { // line 738
// Let's party like it's 1995!
return new BlinkLayout(context, attrs);
}
//...
On line 724 it check that your tag is view and gets true
On line 725 it tries to get class through class attr and gets null
On line 738 it tries to check for blink tag and gets crash
Also, there is a curious thing, Android developers added Easter egg, you can try it:
<view
android:layout_width="wrap_content"
android:layout_height="wrap_content"
class="blink">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:text="Some text" />
</view>

After 2 days I solved this problem use View instead of view
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="#faf4f4"></View>