ControlView.java 文件源码

/**
 * Generates bitmaps used for drawing joystick.
 */
void generateBitmap() {
    // Size and shape of joystick gate
    ShapeDrawable squareShape = new ShapeDrawable();
    squareShape.setShape(new RectShape());
    squareShape.setBounds(0, 0, (int) radius * 2, (int) radius * 2);

    // Create joystick gate bitmap and render shape
    handlesBitmap = Bitmap.createBitmap((int) radius * 2, (int) radius * 2, Bitmap.Config.ARGB_4444);
    Canvas handlesCanvas = new Canvas(handlesBitmap);
    squareShape.getPaint().set(parent.blackPaint);
    squareShape.draw(handlesCanvas);
    parent.strokePaint.setStrokeWidth(standardRadius * .1f);
    squareShape.getPaint().set(parent.strokePaint);
    squareShape.draw(handlesCanvas);
    handlesCanvas.rotate(45, radius, radius);
    squareShape.getPaint().set(parent.clearPaint);
    squareShape.draw(handlesCanvas);
    parent.strokePaint.setStrokeWidth(standardRadius * .05f);
    squareShape.getPaint().set(parent.strokePaint);
    squareShape.draw(handlesCanvas);
}