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Cant start new activity. It keeps crashing

When pressing the button, new activity should open but app instantly crashes. I have searched for answer and making a few adjustments to my code and only thing i dont know how to do is Manifest, can u help me with that?
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="Starting.Programm"
android:versionCode="1"
android:versionName="1.0">
<application android:label="#string/app_name"
android:icon="#drawable/ic_launcher">
<activity 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>
<activity
android:name="InformationActivity"
android:label="#string/app_name"
>
</activity>
</application>
MainActivity:
package Starting.Programm;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
public class MainActivity extends InformationActivity
{
/** Called when the activity is first created. */
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
}
public void startJourney(View view) {
Intent intent = new Intent(this, InformationActivity.class);
startActivity(intent);
}
}
main.xml
<?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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity"
>
<Button android:id="#+id/button_StartApp"
android:layout_width="100dp"
android:layout_height="60dp"
android:text="#string/button_StartApp"
android:layout_gravity="center"
android:layout_marginTop="70dp"
android:layout_marginLeft="115dp"
android:onClick="startJourney"
/>
</LinearLayout>
And next activity which should be opening
package Starting.Programm;
import android.app.Activity;
import android.os.Bundle;
class InformationActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.information);
}
}

<activity> android:name=".InformationActivity" </activity>
Remove android:label="#string/app_name" too. I don't think it is needed.

Add dot to end of pacakager name
package="Starting.Programm."

Application crashes upon new Activity

I know and I do understand that this question has been asked, but I can't seem to interpret it for my application. I am creating an application - using Android Studio - that opens a Activity (called 'About'). When a user clicks on the 'about button' on my MainActivity, it should launch the 'About' activity. However, when I test this out on my device, it says the app has stopped. And on my output panel, it says something about an error with my Manifest.xml file?
MainActivity:
package com.msp.supercarsounds;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void clickedAbout(View view) {
final int result = 1;
Intent AboutButtonClicked = new Intent (this, About.class);
AboutButtonClicked.putExtra("About", "MainActivity");
startActivityForResult(AboutButtonClicked, result);
}
}
AndroidManifest.xml:
<?xml version="1.0" encoding="utf-8"?>
<manifest
xmlns:android="http://schemas.android.com/apk/res/android"
package="com.msp.supercarsounds">
<uses-sdk android:minSdkVersion="17"
android:targetSdkVersion="22"/>
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
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>
</application>
</manifest>
Thank you for your help and time!

You have to declare About activity
<activity android:name=".About">
</activity>
Add this below the </activity> tag of MainActivity

your second activity "about" is not added to manifest.xml add this under the mainactivity
<activity android:name=".about">/activity>

Android layout can not display in device

My Android Studio version is 1.5.1
I have created an XML and it can show well in the AndroidStudio,
but when i run it in genymotion or my phone,it can not show the layout.
I am annoyed at this.I do not know what is wrong.
hope someone could help me.
code image
code:
SplashActivity
import android.content.Intent;
import android.os.Bundle;
import android.os.PersistableBundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
public class SplashActivity extends AppCompatActivity {
private Button mEnterButton;
private View.OnClickListener mOnClickListener = new View.OnClickListener() {
#Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.enter_button:
Intent intent = new Intent(SplashActivity.this, MainActivity.class);
startActivity(intent);
break;
}
}
};
#Override
public void onCreate(Bundle savedInstanceState, PersistableBundle persistentState) {
super.onCreate(savedInstanceState, persistentState);
setContentView(R.layout.activity_splash);
mEnterButton = (Button) findViewById(R.id.enter_button);
mEnterButton.setOnClickListener(mOnClickListener);
}
}
MainActivity
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
findViewById(R.id.button_first).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent=new Intent(MainActivity.this,SplashActivity.class);
startActivity(intent);
}
});
}
}
avtivity_splash_layout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:background="#color/splashBackground">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/splash_tv_text"
android:textSize="28sp"
android:id="#+id/text_splash"
android:textColor="#color/white"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/splash_click_to_inter"
android:id="#+id/enter_button"/>
</LinearLayout>
Manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest
xmlns:android="http://schemas.android.com/apk/res/android"
package="com.geekband.geekbandprojects">
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme" >
<activity android:name=".MainActivity" >
</activity>
<activity android:name=".SplashActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>

Why you need a PersistableBundle ?
make your OnCreateMethod like:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//anything here
}

i'm considering that you haven't already set the SplashActivity as the startup activity.So add the following code(or change it) on Manifest:
<activity
android:name=".Splash"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".MainActivity"/>
And let us know your MainActivity code and of course your Manifest with the logcat.
I will updated my answer after that.
And of course, i think you should use onClick on Oncreate method.

java.lang.IllegalStateException: Could not execute method of the activity - starting new Activity

I am trying to start a New Activity using Intent but I keep getting java.lang.IllegalStateException: Could not execute method of the activity
What am I doing wrong?
Main Activity
package com.example.wrw;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void clicked(View v)
{
Intent intent = new Intent(this, newact.class);
startActivity(intent);
}
}
newact.java
package com.example.wrw;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
public class newact extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.newlayout);
}
}
act_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
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/hello_world" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Start Act"
android:onClick="clicked"
/>
</LinearLayout>
newlayout.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:orientation="vertical" >
</LinearLayout>
Manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.wrw"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="21" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
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>

In android app, all Activity must be configured in the Manifest.xml file firstly, so you should add newact Activity to your manifest
<activity 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>
<activity android:name="com.example.wrw.newact"></activity>

Add this to your manifest file
<activity
android:name=".newact"
android:label="#string/title_activity_login">

Replace this to your MainActivity, this may resolve your problem.
Intent intent = new Intent(MainActivity.this, newact.class);
startActivity(intent);
After this, do not forget to add this in your android menifest file,
<activity
android:name=".newact"
android:label="#string/app_name">
</activity>

try this
Intent intent = new Intent(MainActivity.this, newact.class)
and also register newact in manifest file like this
<activity
android:name=".newact"
android:label="#string/app_name">
</activity>

Moving from one activity to another Activity in Android

I want to move from one activity to another (using virtual device). When I click on button to move, My emulator ones a dialog box showing unfortunately SMS1 has stopped working (SMS1 is my app name).
Can anybody help me in correcting my code?
MainActivity.java:
package com.example.sms1;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
public class MainActivity extends Activity implements OnClickListener
{
Button b1;
TextView tv1;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
b1 = (Button) findViewById(R.id.button1);
tv1 = (TextView) findViewById(R.id.textView1);
b1.setOnClickListener(this);
}
#Override
public boolean onCreateOptionsMenu(Menu menu)
{
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public void onClick(View v)
{
// TODO Auto-generated method stub
Intent i = new Intent(getApplicationContext(),NextActivity.class);
startActivity(i);
setContentView(R.layout.avtivity_next);
}
}
Here is the NextActivity
package com.example.sms1;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.TextView;
public class NextActivity extends Activity {
TextView tv1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.avtivity_next);
tv1 = (TextView) findViewById(R.id.textView1);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
Manifest.XML
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.sms1"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.example.sms1.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>
NextActivityLayout
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context=".NextActivity" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="next activity" />
</RelativeLayout>
MainActivity Layout
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/hello_world" />
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/textView1"
android:layout_marginTop="80dp"
android:layout_toRightOf="#+id/textView1"
android:text="Button" />
</RelativeLayout>

First You have to use this code in MainActivity.java class
#Override
public void onClick(View v)
{
// TODO Auto-generated method stub
Intent i = new Intent(getApplicationContext(),NextActivity.class);
startActivity(i);
}
You can pass intent this way.
Second
add proper entry into manifest.xml file.
<activity android:name=".NextActivity" />
Now see what happens.

You haven't defined NextActivity in the AndroidManifest.xml file.
Add these lines in android manifest after</activity> tag. It should work.
<activity
android:name=".NextActivity" >
</activity>
final code will be
<application
android:allowBackup="true"
android:icon="#drawable/app_icon"
android:label="#string/app_name" >
<activity
android:name=".MainActivity"
android:label="Main Activity" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".NextActivity" >
</activity>
</application>

button1 in activity2
code written in activity 2
button1.setOnClickListener(new View.OnClickListener() {
public void onClick(View v)
{
// starting background task to update product
Intent fp=new Intent(getApplicationContext(),activity1.class);
startActivity(fp);
}
});
This might help

Simply add your NextActivity in the Manifest.XML file
<activity
android:name="com.example.sms1.NextActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
</intent-filter>
</activity>

public void onClick(View v)
{
startActivity(new Intent(getApplicationContext(), Next.class));
}
it is direct way to move second activity and there is no need for call intent

#Override
public void onClick(View v)
{
// TODO Auto-generated method stub
Intent intent = new Intent(Activity1.this,Activity2.class);
startActivity(intent);
}

1) place setContentView(R.layout.avtivity_next); to the next-activity's onCreate() method just like this (main) activity's onCreate()
2) if you have not defined the next-activity in your-apps manifest file then do this also, like:
<application
android:allowBackup="true"
android:icon="#drawable/app_icon"
android:label="#string/app_name" >
<activity
android:name=".MainActivity"
android:label="Main Activity" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".NextActivity"
android:label="Next Activity" >
</activity>
</application>
You must have to perform the 2nd step every time you create a new activity, otherwise your app will crash

When you have to go from one page to another page in android changes made in 2 files
Intent intentSignUP = new Intent(this,SignUpActivity.class);
startActivity(intentSignUP);
add activity in androidManifest file also like
<activity android:name=".SignUpActivity"></activity>

setContentView(R.layout.avtivity_next);
I think this line of code should be moved to the next activity...

Below code is working fine with Android 4.3:
Intent i = new Intent(this,MainActivity2.class);
startActivity(i);

First you have to declare the activity in Manifest. It is important. You can add this inside application like this.

It is mainly due to unregistered activity in manifest file as "NextActivity"
Firstly register NextActivity in Manifest like
<activity android:name=".NextActivity">
then use the code in the where you want
Intent intent=new Intent(MainActivity.this,NextActivity.class);
startActivity(intent);
where you have to call the NextActivity..

Register your java class on Android manifest file
After that write this code on button click
startActivity(new intent(MainActivity.this,NextActivity.class));

You can do
Intent i = new Intent(classname.this , targetclass.class);
startActivity(i);