A really useful gist which helps to create pressed state for Android's Button/ImageButton without using additional drawbles

MultiStateDrawable.java

package net.leolink.android.gist;

public class MultiStateDrawable extends LayerDrawable {
	// The color filter to apply when the button is pressed
	protected ColorFilter _pressedFilter = new LightingColorFilter(Color.GRAY, 1);

	public MultiStateDrawable(Drawable d) {
		super(new Drawable[] { d });
	}

	@Override
	protected boolean onStateChange(int[] states) {
		boolean enabled = false;
		boolean pressed = false;

		for (int state : states) {
			if (state == android.R.attr.state_enabled)
				enabled = true;
			else if (state == android.R.attr.state_pressed)
				pressed = true;
		}

		mutate();
		if (enabled) {
			if (pressed) {
		    		setColorFilter(_pressedFilter);
			} else {
		    		setColorFilter(null);
			}
		} else {
			setColorFilter(_pressedFilter);
		}

		invalidateSelf();

		return super.onStateChange(states);
	}

	@Override
	public boolean isStateful() {
		return true;
	}
}

StatefulImageButton.java

package net.leolink.android.gist;

public class StatefulImageButton extends ImageButton {
	public StatefulImageButton(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
	}
	public StatefulImageButton(Context context, AttributeSet attrs) {
		super(context, attrs);
	}
	public StatefulImageButton(Context context) {
		super(context);
	}

	@SuppressLint("NewApi")
	@Override
	public void setBackground(Drawable background) {
		MultiStateDrawable msd = new MultiStateDrawable(background);
		if (Build.VERSION.SDK_INT < 16)
			super.setBackgroundDrawable(msd);
		else
			super.setBackground(msd);
	}
	
	@Override
	public void setImageDrawable(Drawable drawable) {
		MultiStateDrawable msd = new MultiStateDrawable(drawable);
		super.setImageDrawable(msd);
	}
}