I am doing the simplest thing in an activity of an application I am making. In this activity I am just opening an activity when a user clicks a button. At Runtime the application crashes and the logcat shows that there is a 'NullPointException'. Cannot Figure out the reason behind this Exception. log shows
Caused by: java.lang.NullPointerException
at com.example.lenovo.hitchhbo.GameOver.onCreate(GameOver.java:47)
at android.app.Activity.performCreate(Activity.java:5231)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2148)
and my Activity is
public class GameOver extends Activity {
//TextView GO;
Button cont;
Intent startAgain;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getActionBar().hide();
getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE
| View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
| View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
| View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
| View.SYSTEM_UI_FLAG_FULLSCREEN
| View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
| View.INVISIBLE);
cont=(Button)findViewById(R.id.button1);
startAgain=new Intent(this,LauncherActivity2.class);
cont.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
cont.setTextColor(Color.argb(255,0,0,0));
//overridePendingTransition(R.anim.transition1,R.anim.transition2);
startActivity(startAgain);
}
});
setContentView(R.layout.activity_game_over);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.game_over, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
According to Log the error is at
cont.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
cont.setTextColor(Color.argb(255,0,0,0));
//overridePendingTransition(R.anim.transition1,R.anim.transition2);
startActivity(startAgain);
}
});
This is crazy when I have initialized cont in line
cont=(Button)findViewById(R.id.button1);
What can be the problem with this?
You have to call
setContentView(R.layout.activity_game_over);
before you call
cont=(Button)findViewById(R.id.button1);
The reason for this is that it's searching for a button in a view that doesn't exist yet.
And also you should initialize your Intent
object startAgain
. It is null
now. See that:
cont=(Button)findViewById(R.id.button1);
//it is just a comment:
//startAgain=new Intent(this,LauncherActivity2.class);
cont.setOnClickListener(new View.OnClickListener() {
...
You should remove this comment tag.
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