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I'm experiencing a NullpointerException with this code: kuglebutton.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { if(toggle.isChecked()) { counter1 = counter1 + 10; column1tv.setText("" + counter1); } else { counter1 = counter1 - 2; column1tv.setText("" + counter1); } } }); Can anyone tell me what i'm doing wrong, and maybe how to fix it?

I've got this ToggleButton which is supposed to change the drawables (and functions) of some other buttons upon toggling on/off. So far i've only managed to make it work one way, by using this code. @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); setContentView(R.layout.main); toggle = (ToggleButton) findViewById(R.id.bRedGreen); toggle.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub minuskugle = (Button) findViewById(R.id.bBallhole); minuskugle.setBackgroundResource(R.drawable.redballinhole); } }); } How do you make it change the drawable back to default upon another click? _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ _ __ ...