Question

I’m attemping to add a new LinearLayout defined by xml on top of my opengl view.

I have this working by using pure java:

public class VortexView extends GLSurfaceView {
 public boolean onTouchEvent(final MotionEvent event) {
        show_something();
 }

void show_something()
{
  //context is the main activity object that gets passed into this
  LinearLayout ll = new LinearLayout(context);
  b = new Button(context);
  b.setText("hello world 1");
  ll.addView(b);
  ll.setGravity(Gravity.CENTER_HORIZONTAL | Gravity.CENTER_VERTICAL);
  context.addContentView(ll, new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));
}
}

However I want to be able to do this:

LinearLayout ll = (LinearLayout)findViewById(R.layout.main);
context.addContentView(ll, new LayoutParams(LayoutParams.FILL_PARENT,  LayoutParams.FILL_PARENT));

My xml is:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
          android:layout_width="fill_parent" 
          android:layout_height="fill_parent" 
          android:orientation="vertical" >
<Button
    android:id="@+id/button1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:padding="10dp"
    android:text="kill"
    />
</LinearLayout>

Everytime I do this though the app crashes. Any ideas?

Answer 1

Is it possible you are making a mess there?
Let’s try it in a different way, create a GLSurfaceView at the background, and add the LinearLayout on top of it.

main.xml file:

    <?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout 
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/relativeLayout"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" >

        <path.to.vortex.VortexView
            android:id="@+id/vortexView"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:layout_alignParentLeft="true"
            android:layout_alignParentTop="true" >
        </path.to.vortex.VortexView>

 <LinearLayout
            android:id="@+id/linearLayout"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent" >
   </LinearLayout>
</RelativeLayout>

in your VortexView class add constructors and initilazation

  public class VortexView extends GLSurfaceView {

    public VortexView (Context context)
    {
        super(context);
        init(context);
    }

    public VortexView (Context context, AttributeSet atts)
    {
        super(context, atts);
        init(context);
    }

    public VortexView (Context context, AttributeSet atts, int defStyle)
    {
        super(context, atts, defStyle);
        init(context);
    }

    public void init(context)
    {
        //do whatever you need to init your view here...
    }
}

In your activity you’ll need to setContentView() on your main.xml:

public class VortexActivity extends Activity
{
    Context mContext;
    VortexView mVortexView;
    RelativeLayout relativeLayout;

    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        mContext = getApplicationContext();
        setContentView(R.layout.main);

        mVortexView = (VortexView) findViewById(R.id.vortexView);
        mRelativeLayout = (RelativeLayout) findViewById(R.id.relativeLayout);
    }
}

now you are free to do whatever you wish with your layouts, and since the VortexView was declared in the xml before the LinearLayout it will be in it’s background.