【android seekbar 增大拖動區域】

//seekbarLayout 是seekBar對象statusSeekbar的父層布局
seekbarLayout = mStatusViewLayout.findViewById(R.id.id_seekbar_layout);
seekbarLayout.setOnTouchListener(new View.OnTouchListener() {
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        Rect seekRect = new Rect();
        statusSeekbar.getHitRect(seekRect);
        if ((event.getY() >= (seekRect.top - 500)) && (event.getY() <= (seekRect.bottom + 500))) {
            float y = seekRect.top + seekRect.height() / 2;
            //seekBar only accept relative x
            float x = event.getX() - seekRect.left;
            if (x < 0) {
                x = 0;
            } else if (x > seekRect.width()) {
                x = seekRect.width();
            }
            MotionEvent me = MotionEvent.obtain(event.getDownTime(), event.getEventTime(),
                    event.getAction(), x, y, event.getMetaState());
            return statusSeekbar.onTouchEvent(me);
        }
        return false;
    }
});

原理：給一個大一點面積的View 獲取觸摸事件，直接手動調用seekbar onTouchEvent.