Creating a listener onRotate()

I've been trying to find a listener that can execute seekmark.markPlace(). The function takes in the dimensions and padding for a seekBar defined in my layout. When I call the function from onCreate it returns 0 for the values of the seekBar. I need a listener that can call the function outside of onCreate. The function should only run if the screen is rotated (when layout-land is created).

    public class seekMark {
    private int seekLength;     // in pixels 
    private int seekLeftPad;    // in pixels
    private int seekBottomPad;  // in pixels
    private int trackLength;    // in ms

    public seekMark(){
        seekLength = progressBar.getWidth();
        seekLeftPad = progressBar.getPaddingLeft();
        seekBottomPad 开发者_如何学C= progressBar.getPaddingBottom();
        trackLength = player.getDuration();
    }

    private int pxPerMs(){
        return (seekLength/trackLength);
    }

    public void markPlace() throws XmlPullParserException, IOException {
        Drawable marker = context.getResources().getDrawable(R.drawable.audio);
        int y = seekBottomPad;
        int x = 0;
        int w = marker.getIntrinsicWidth();
        int h = marker.getIntrinsicHeight();
        int[] bmPos = markPxList(); // returns a list of px (from the left) read from a xml database

        for(int i = 0; i <= bmPos.length; i++){
            x = bmPos[i] + seekLeftPad;
            marker.setBounds( x, y, x + w, y + h );
            marker.draw( canvas );
        }

    }

}

Is it possible to make your own listener like onRotate() or something?

Since onCreate is going to be called when the device is rotated anyways, why not just use a private variable to store the orientation of the display. Each time onCreate() is called, you can compare to see if the display orientation is changed:

Display display = ((WindowManager) getSystemService(WINDOW_SERVICE)).getDefaultDisplay();
int rotation = display.getRotation();

if(rotation != mPreviousRotation) {
    mPreviousRotation = rotation;

    // Insert code for handling rotation here
}

I'll leave it to you to decide how to handle initialization of the mPreviousRotation variable during the first invocation of onCreate().