Button Start New Activity cannot start?

Question

i have created apps in eclipse with target sdk in API 15 and. I want to make button start new activity. i have created that code but i have a problem. when i run in on my phone ninetology stealh 2, when i click a button and my app has crash and my phone show me this :

"Unfortunately start"

i have tested it in others phone two and it show same problem. i also use more technique that i learn from thenewboston, vongella an other but still have same problem. here is my .xml and java code :-

1. menu.java

package com.mytuturkiu.mytuturkiu;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;                                                                                                                                                                                                                       
import android.widget.Button;
import android.content.Intent;

    public class Menu extends Activity {

      Button btnmodul;

      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_menu);

          btnmodul = (Button)findViewById(R.id.btnmodul);      
            btnmodul.setOnClickListener(new View.OnClickListener() {

              @Override
              public void onClick(View v) {
          // TODO Auto-generated method stub
              Intent vokal = new Intent(v.getContext(),Modul_Vokal.class);
              startActivity(vokal);
          }
      } );

  }



}

1. Modul_vokal.java

package com.mytuturkiu.mytuturkiu;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;

public class Modul_Vokal extends Activity {

  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_modul__vokal);
  }

  @Override
  public boolean onCreateOptionsMenu(Menu menu) {
      // Inflate the menu; this adds items to the action bar if it is present.
      getMenuInflater().inflate(R.menu.modul__vokal, menu);
      return true;
  }

}

1. AndroidManifest.xml

   <uses-sdk
       android:minSdkVersion="14"
       android:targetSdkVersion="15" />
   
   <application
       android:allowBackup="true"
       android:icon="@drawable/ic_launcher"
       android:label="@string/app_name"
       android:theme="@style/AppTheme" >
       <activity
           android:name="com.mytuturkiu.mytuturkiu.Menu"
           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.mytuturkiu.mytuturkiu.Modul_Vokal"
           android:label="@string/title_activity_modul__vokal" >
       </activity>
   
   </application>
   

what problem with my apps?..

Answer 1

Try,

 Intent vokal = new Intent(getApplicationContext(),Modul_Vokal.class);
              startActivity(vokal);

in place of,

   Intent vokal = new Intent(v.getContext(),Modul_Vokal.class);
              startActivity(vokal);

It will definately work my friend.

Answer 2

You can add a function like this in your class:

  public class Menu extends Activity {

  Button btnmodul;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_menu);

      btnmodul = (Button)findViewById(R.id.btnmodul);      
      btnmodul.setOnClickListener(new View.OnClickListener() {

          @Override
          public void onClick(View v) {
            // CALL THE FUNCTION
            startMyActivity();
          }
      } );

  }

  private void startMyActivity(){
         Intent vokal = new Intent(this,Modul_Vokal.class);
         startActivity(vokal);
  }

}

The function is in your activity context and when you put "this" in the Intent constructor, it will take the correct one.

Answer 3

You should not do v.getContext()... You should use getApplicationContext()..

The View v is the view you clicked on. So v.getContext() returns the context which the view runs on. This is the issue.

I think using Application's context is better and doesn't cause an issue.