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android - How do I declare a TextView variable so that I can use it anywhere?

I have started coding in java/android just today so excuse me if I am being a total idiot here.

I have been facing this problem for the past hour, I have tried to google it but couldn't find any answers.

How do I declare a TextView as a static/variable so that I can access it simply by typing "variablename." anywhere in my code?

I am not trying to access the TextView from another activity, these are all in the same one.

This is what my code looks like(all in mainactivity.java) :

public class MainActivity extends Activity {

    TextView test = (TextView)findViewById(R.id.textView2);

    public void registermessage(View view) {
        test.setText("Test");
    }
}

This doesn't give any errors in Eclipse but will simply force close when I try to run it on my phone.

I can succeed when I move the line I declare test as a textview to the public void but I want to be able to use the variable test from any void in the activity.

Thank you!

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You have to instantiate the variable after the setcontentView method was called, so you have to do the following:

public class MainActivity extends Activity {

TextView test;

@Override
onCreate(Bundle s){
    ...
    setContentView(R.layout.yourLayout);
    test = (TextView)findViewById(R.id.textView2);
}


public void registermessage(View view) {

    test.setText("Test");
}

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