Question

so from debugging and commenting out things i have come to the conclusion that the problem from this program is in the addTextView() method. I have absolutely no idea where the problem is going wrong. My guess is in the layout that i am trying to add to the TextView.
thanks you so much in advance for your help.

public class Books extends Activity{
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.books);
        addTextView("Hello World");
    }


    public void addTextView(String text)
    {
        ScrollView viewport = (ScrollView)findViewById(R.id.books);
        TextView textview= (TextView)new TextView(this);
        textview.setText(text);
        //textview.setLayoutParams(new ScrollView.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
        viewport.addView(textview, new ScrollView.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
    }

    public void addButton(String text)
    {
        ScrollView scrollview = (ScrollView)findViewById(R.id.books);
        Button btnTag = (Button)new Button(Books.this);
        btnTag.setLayoutParams(new ScrollView.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
        btnTag.setText(text);
        scrollview.addView(btnTag);
    }

}

Answer 1

ScrollViews can only have one child, typically a LinearLayout. When you call scrollview.addView(blah blah) you’re adding more children to the ScrollView which is not allowed.

See here for documentation about ScrollView.

—

On a side note, when posting questions on StackOverflow about errors you encounter, please state:

• the error you encounter (in Android, this’ll be found in the LogCat view)
• your expected results (what you were trying to do)
• the relevant code (in this case, you should include your layout XML file too – while the ScrollView error is definitely one of the errors you’ll get, it might not be the first one that needs fixing, in order to move forward).

It’ll help everyone, including people in future who stumble upon this question.