Droplet.java 文件源码

/**
 * @Overrided method that handles the core portion, <br>
 * @warning Dont change the implementation
 * This method get called when ever a invalidate is invoked
 */
@Override
protected void onDraw(Canvas canvas) {
    // Gets the whole available width to work on
    width = canvas.getWidth();

    Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.reload);
    // Create a mutable bitmap to work on. @warning dont load large images 
    Bitmap mutableBitmap = bitmap.copy(Bitmap.Config.ARGB_8888, true);

    // Set the radius based on image width
    RADIUS = bitmap.getWidth() / 2;

    calculatePoints();
    // release unused bitmap memory
    bitmap.recycle();
    Path _path = new Path();

    if(distance < REFRESH_POSITION && distance >= 0)
    {
        // Rough Y point which bend to pass through
        BEND_POINT_Y = distance/2;
        // Rough X point which bend to pass through
        BEND_POINT_X = distance/5;

        _path.moveTo(top_X1, CENTER_POINT_Y); 
        _path.quadTo(top_X1 + BEND_POINT_X, CENTER_POINT_Y + BEND_POINT_Y, bottom_X1, CENTER_POINT_Y + distance);

        /* Calculate the radius of the bottom arc */
        int bottomRadius = (bottom_X2 - bottom_X1)/2; 

        _path.quadTo(bottom_X1 + bottomRadius, CENTER_POINT_Y + distance + bottomRadius, bottom_X2, CENTER_POINT_Y + distance);
        _path.quadTo(top_X2 - BEND_POINT_X, CENTER_POINT_Y + BEND_POINT_Y, top_X2, CENTER_POINT_Y );

        _path.lineTo(top_X1, CENTER_POINT_Y);

        _path.setFillType(FillType.WINDING);
    }
    _path.close();

    // Draw on canvas
    canvas.drawPath(_path, paint);
    canvas.drawBitmap(mutableBitmap, (width/2) - RADIUS, CENTER_POINT_Y - RADIUS, paint);

    refreshList();
    mutableBitmap.recycle();
}