Android SeekBar Flipped Horizontally

With the Android SeekBar, you can normally drag the thumb to the left or to the right and the yellow progress color is to the left of the thumb. I want the exact opposite, essentially flipping the yellow progress color to the right of the thumb and flipping the entire SeekBar on the y-axis.

Can a开发者_StackOverflow中文版nyone point me in the right direction? Thanks!

After fiddling around with some code this is what I got and it seems to work pretty well. Hopefully it will help someone else in the future.

public class ReversedSeekBar extends SeekBar {

    public ReversedSeekBar(Context context) {
        super(context);
    }

    public ReversedSeekBar(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public ReversedSeekBar(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        float px = this.getWidth() / 2.0f;
        float py = this.getHeight() / 2.0f;

        canvas.scale(-1, 1, px, py);

        super.onDraw(canvas);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        event.setLocation(this.getWidth() - event.getX(), event.getY());

        return super.onTouchEvent(event);
    }
}

This was thrown together with the help of these two questions:

1. How can you display upside down text with a textview in Android?
2. How can I get a working vertical SeekBar in Android?

Have you tried seekbar.setRotation( 180 )? It flips the seekbar 180 degrees and is upside down, meaning left side is max, right side is 0 with the color on the right of the thumb. No need to create a custom seekbar this way.

Have you tried setting this in xml

            android:rotationY="180"

You should look into making a custom progress bar. Considering what you want to do, you already have the images you need in the Android SDK. I'd extract them and edit them accordingly. Here's a tutorial to help get you started.

This should fix a few issues with @mhenry answer

class ReverseSeekBar : SeekBar {
    constructor(context: Context) : super(context) {
        init()
    }
    constructor(context: Context, attrs: AttributeSet?) : super(context, attrs) {
        init()
    }
    constructor(context: Context, attrs: AttributeSet?, defStyle: Int) : super(context, attrs, defStyle) {
        init()
    }

    var first = true

    override fun onTouchEvent(event: MotionEvent): Boolean {
        event.setLocation(this.width - event.x, event.y)
        return super.onTouchEvent(event)
    }

    override fun getProgress(): Int {
        return max - super.getProgress() + min
    }

    override fun setProgress(progress: Int) {
        super.setProgress(max - progress + min)
    }

    override fun onDraw(canvas: Canvas?) {
        if (first) {
            first = false
            val old = progress
            progress = min + max - progress
            super.onDraw(canvas)
            progress = old
        } else
            super.onDraw(canvas)
    }

    private fun init() {
        rotation = 180f
    }

}