Develop Reference

android.content.ActivityNotFoundException: Unable to find explicit activity class {com.myapp/androidx.fragment.app.FragmentActivity}

I am using BottomNavigation Menu in my app which has 4 submenus: Address, Dashboard, Home, Notifications.
When I want to startActivity from HomeFragment to Dashboard Fragment it gives me error that I have depicted below.
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.karatasyazilim.su, PID: 21216
android.content.ActivityNotFoundException: Unable to find explicit activity class {com.karatasyazilim.su/androidx.fragment.app.FragmentActivity}; have you declared this activity in your AndroidManifest.xml?
at android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:2069)
at android.app.Instrumentation.execStartActivity(Instrumentation.java:1717)
at android.app.Activity.startActivityForResult(Activity.java:5252)
at androidx.fragment.app.FragmentActivity.startActivityForResult(FragmentActivity.java:675)
at androidx.core.app.ActivityCompat.startActivityForResult(ActivityCompat.java:234)
at androidx.fragment.app.FragmentActivity.startActivityFromFragment(FragmentActivity.java:790)
at androidx.fragment.app.FragmentActivity$HostCallbacks.onStartActivityFromFragment(FragmentActivity.java:932)
at androidx.fragment.app.Fragment.startActivity(Fragment.java:1257)
at androidx.fragment.app.Fragment.startActivity(Fragment.java:1245)
at com.karatasyazilim.su.ui.home.HomeFragment$5.onClick(HomeFragment.java:333)
at android.view.View.performClick(View.java:7869)
at android.widget.TextView.performClick(TextView.java:14958)
at com.google.android.material.button.MaterialButton.performClick(MaterialButton.java:992)
at android.view.View.performClickInternal(View.java:7838)
at android.view.View.access$3600(View.java:886)
at android.view.View$PerformClick.run(View.java:29362)
at android.os.Handler.handleCallback(Handler.java:883)
at android.os.Handler.dispatchMessage(Handler.java:100)
at android.os.Looper.loop(Looper.java:237)
at android.app.ActivityThread.main(ActivityThread.java:8016)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:496)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1087)
My manifest is :
<?xml version="1.0" encoding="utf-8"?>
<uses-permission android:name="android.permission.INTERNET" />
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/Theme.Su">
<activity android:name=".CreateAddress"></activity>
<activity android:name=".PhoneActivation" />
<activity
android:name=".Genel"
android:label="#string/title_activity_genel" />
<activity android:name=".SignUp" />
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<meta-data
android:name="com.facebook.sdk.ApplicationId"
android:value="#string/facebook_app_id" />
<activity
android:name="com.facebook.FacebookActivity"
android:configChanges="keyboard|keyboardHidden|screenLayout|screenSize|orientation"
android:label="#string/app_name" />
<activity
android:name="com.facebook.CustomTabActivity"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.DEFAULT" />
<category android:name="android.intent.category.BROWSABLE" />
<data android:scheme="#string/fb_login_protocol_scheme" />
</intent-filter>
</activity>
</application>
And here is my activiy code.
Intent kalimera = new Intent(getActivity(), FragmentActivity.class);
startActivity(kalimera);
What am I doing wrong?

You're trying to start the androidx FragmentActivity class directly. This is a parent class that you should subclass to create your own Activity.
Instead, make sure that you're using the name of the Activity you want to launch instead:
Intent intent = new Intent(getActivity(), NameOfTheActivityThatYouWantToLaunch.class);
startActivity(intent);
Alternately, if you aren't trying to launch an Activity and just got this code from somewhere, simply remove those lines.
If you're trying to launch a Fragment instead, take a look at How to start Fragment from an Activity

android sdk product flavors - activity not found when I start a new activity using intent

I have a working app to which I have added 2 product flavors. This app has a menu on the first screen which allows the user to choose the next activity, which I load with an intent.
Here is AndroidManifest.xml:
<?xml version="1.0" encoding="utf-8"?>
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity
android:name="com.alpha.aloedu.MainActivity"
android:screenOrientation="portrait">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.alpha.aloedu.guideddrawing.GuidedLetterDrawingActivity"
android:label="Guided Letter Drawing"
android:screenOrientation="portrait" />
<activity
android:name="com.alpha.aloedu.buildvocabulary.BuildVocabularyActivity"
android:label="Image Plus Word"
android:screenOrientation="portrait" />
<activity
android:name="com.alpha.aloedu.findthepicture.FindThePictureActivity"
android:label="Find the Picture"
android:screenOrientation="portrait" />
<activity
android:name="com.alpha.aloedu.findtheletter.FindTheLetterActivity"
android:label="Find the Letter"
android:screenOrientation="portrait" />
<activity
android:name="com.alpha.aloedu.fillintheletter.FillInTheLetterActivity"
android:label="Find the Letter"
android:screenOrientation="portrait" />
<activity
android:name="com.alpha.aloedu.EndActivity"
android:label="End Activity"
android:screenOrientation="portrait" />
<activity
android:name="com.alpha.aloedu.AdminActivity"
android:label="Admin Activity"
android:theme="#style/AppTheme.NoActionBar"
android:screenOrientation="portrait"
/>
</application>
<supports-screens
android:largeScreens="true"
android:normalScreens="true"
android:requiresSmallestWidthDp="480"
android:resizeable="false"
android:smallScreens="false"
android:xlargeScreens="true" />
Here is the relevant portion of the gradle file:
productFlavors {
de {
applicationIdSuffix ".de"
versionName "1.1de"
}
fr {
applicationIdSuffix ".fr"
versionName "1.1fr"
}
}
Here is the source tree:
Here is the code where I load the next activity:
Intent intent = new Intent();
intent.setClassName("com.alpha.aloedu", newClassName);
currentActivity.startActivity(intent);
currentActivity.finish();
I have set a breakpoint on the second line and "newClassName" has the correct value. However, when I run the "deDebug" variant, I get an error on the third line:
android.content.ActivityNotFoundException:
Unable to find explicit activity class
{com.alpha.aloedu/com.alpha.aloedu.guideddrawing.GuidedLetterDrawingActivity};
have you declared this activity in your AndroidManifest.xml?
The class GuidedLetterDrawingActivity does exist in the main source tree, and also in AndroidManifest.xml.
Thank you for any help you can provide.

You must declare activities of each flavor in its manifest file
...\src\ de \AndroidManifest.xml
...\src\ fr \AndroidManifest.xml

Declare each new activity in manifest. Even if you change the name you have to modify the manifest file.
<application
android:allowBackup="true"
android:icon="#drawable/icon"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".new_Activity"
android:label="#string/app_name"/>
<activity
android:name=".new_Activity2"
android:label="#string/app_name"/>
</application>
This has to be declared in main java file
Intent intent = new Intent(MainActivity.this, newActivity.class);
startActivity(intent);
Intent intent1 = new Intent(MainActivity.this, newActivity2.class);
startActivity(intent1);
execute the intent block of code as per your requirement in the same or different functions.

Cause of Error Message "Error:(27) Tag <manifest> attribute package has invalid type 4."

When trying to build my app, I get the following error message: "Error:(27) Tag <manifest> attribute package has invalid type 4." Any ideas on what is causing this? Here is a copy of my manifest:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.dummy.tanc">
<application
android:supportsRtl="true"
android:allowBackup="true"
android:fullBackupContent="false"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<meta-data android:name="com.google.android.gms.games.APP_ID"
android:value="#string/app_id" />
<meta-data android:name="com.google.android.gms.version"
android:value="#integer/google_play_services_version"/>
<activity
android:name="com.google.example.games.tanc.MainActivity"
android:label="#string/title_activity_main"
android:screenOrientation="portrait" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>

I think it is because, in your manifest, you've set your package name (line 2) to be
package="com.dummy.tanc"
and in when defining the activity (line 18), you've used
android:name="com.google.example.games.tanc.MainActivity"
Because of this mismatch, the issue could be arising. Change the line 18 to
android:name="com.dummy.tanc.MainActivity"

It means attribute package has type float but not string.
I guess your package name contains only numbers, something like package="1.0".

error AppCompat you need use app.themecompat

referring to thread Unfortunately, 'app_name' has stopped, I solved it, I get a new error:
FATAL EXCEPTION: main
Process: com.cursoandroid.miarrayadapter, PID: 1253
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.cursoandroid.miarrayadapter/com.cursoandroid.miarrayadapter.MainActivity}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
at android.app.ActivityThread
Mi main Activity is already app.compat
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.cursoandroid.miarrayadapter" >
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/Theme.AppCompat" >
<activity
android:theme="#style/Theme.AppCompat"
android:name=".MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
But I´m geeting to execute the application:
I dont understand it?

Since you are using the appcompat library the xmlns attribute in menu_main.xml should be:
<menu xmlns:yourapp="http://schemas.android.com/apk/res-auto" .... >
as given in the android documentation:
http://developer.android.com/guide/topics/ui/actionbar.html

I haveSecurityException: Permission Denial error

I am getting the following error:
ActivityManager: java.lang.SecurityException: Permission Denial: starting Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10000000 cmp=com.optionpricing/.optionListNew } from null (pid=1160, uid=2000) requires null
I am new to programming in Android and I could not make sense of the other postings related to my problem. I wonder if there is an issue with the optionListNew class? Can someone lend a hand so I can move on to completing my app. Also, the app runs in my virtual device, and I only get this error when I try to test it on my actual phone.
Any ideas are appreciated. Below is the manifest file.
<?xml version="1.0" encoding="UTF-8"?>
<manifest android:versionCode="1" android:versionName="1.0"
package="com.optionpricing" xmlns:android="http://schemas.android.com/apk/res/android">
<uses-sdk android:minSdkVersion="8"/>
<application android:icon="#drawable/icon"
android:label="#string/app_name"
android:debuggable="true">
<activity android:name=".optionListNew">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<activity android:name=".OptionPricing"/>
<activity android:name=".optionListNew"/>
<activity android:name=".futureOptionActivity"/>
<activity android:name=".currencyOptionActivity"/>
<activity android:name=".gapOptionActivity"/>
<activity android:name=".gapOptionList01"/>
<activity android:name=".barrierSingleUpInActivity"/>
<activity android:name=".testActivity"/>
<activity android:name=".barrierlistview"/>
<activity android:name=".barrierSingleDownInActivity"/>
</application>
</manifest>

You added "optionListNew" activity twice in the manifest file.. remove below activity by deleting this line
<activity android:name=".optionListNew"/>
Your Manifest.xml code will become
<?xml version="1.0" encoding="UTF-8"?>
<manifest android:versionCode="1" android:versionName="1.0"
package="com.optionpricing" xmlns:android="http://schemas.android.com/apk/res/android">
<uses-sdk android:minSdkVersion="8"/>
<application android:icon="#drawable/icon"
android:label="#string/app_name"
android:debuggable="true">
<activity android:name=".optionListNew">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<activity android:name=".OptionPricing"/>
<activity android:name=".futureOptionActivity"/>
<activity android:name=".currencyOptionActivity"/>
<activity android:name=".gapOptionActivity"/>
<activity android:name=".gapOptionList01"/>
<activity android:name=".barrierSingleUpInActivity"/>
<activity android:name=".testActivity"/>
<activity android:name=".barrierlistview"/>
<activity android:name=".barrierSingleDownInActivity"/>
</application>
</manifest>

optionListNew is present twice in the manifest. Remove the second.