@Override protected void onDraw(Canvas canvas) { for (int i = 0; i < balls.size(); ++i) { ShapeHolder shapeHolder = balls.get(i); canvas.save(); canvas.translate(shapeHolder.getX(), shapeHolder.getY()); shapeHolder.getShape().draw(canvas); canvas.restore(); } }
private ShapeHolder addBall(float x, float y) { OvalShape circle = new OvalShape(); circle.resize(50f, 50f); ShapeDrawable drawable = new ShapeDrawable(circle); ShapeHolder shapeHolder = new ShapeHolder(drawable); shapeHolder.setX(x - 25f); shapeHolder.setY(y - 25f); int red = (int) (Math.random() * 255); int green = (int) (Math.random() * 255); int blue = (int) (Math.random() * 255); int color = 0xff000000 | red << 16 | green << 8 | blue; Paint paint = drawable.getPaint(); // new Paint(Paint.ANTI_ALIAS_FLAG); int darkColor = 0xff000000 | red / 4 << 16 | green / 4 << 8 | blue / 4; RadialGradient gradient = new RadialGradient(37.5f, 12.5f, 50f, color, darkColor, Shader.TileMode.CLAMP); paint.setShader(gradient); shapeHolder.setPaint(paint); balls.add(shapeHolder); return shapeHolder; }
@Override public boolean onTouchEvent(MotionEvent event) { if (event.getAction() != MotionEvent.ACTION_DOWN && event.getAction() != MotionEvent.ACTION_MOVE) { return false; } ShapeHolder newBall = addBall(event.getX(), event.getY()); // Bouncing animation with squash and stretch float startY = newBall.getY(); float endY = getHeight() - 50f; float h = (float) getHeight(); float eventY = event.getY(); int duration = (int) (500 * ((h - eventY) / h)); ValueAnimator bounceAnim = ObjectAnimator.ofFloat(newBall, "y", startY, endY); bounceAnim.setDuration(duration); bounceAnim.setInterpolator(new AccelerateInterpolator()); ValueAnimator squashAnim1 = ObjectAnimator.ofFloat(newBall, "x", newBall.getX(), newBall.getX() - 25f); squashAnim1.setDuration(duration / 4); squashAnim1.setRepeatCount(1); squashAnim1.setRepeatMode(ValueAnimator.REVERSE); squashAnim1.setInterpolator(new DecelerateInterpolator()); ValueAnimator squashAnim2 = ObjectAnimator.ofFloat(newBall, "width", newBall.getWidth(), newBall.getWidth() + 50); squashAnim2.setDuration(duration / 4); squashAnim2.setRepeatCount(1); squashAnim2.setRepeatMode(ValueAnimator.REVERSE); squashAnim2.setInterpolator(new DecelerateInterpolator()); ValueAnimator stretchAnim1 = ObjectAnimator.ofFloat(newBall, "y", endY, endY + 25f); stretchAnim1.setDuration(duration / 4); stretchAnim1.setRepeatCount(1); stretchAnim1.setInterpolator(new DecelerateInterpolator()); stretchAnim1.setRepeatMode(ValueAnimator.REVERSE); ValueAnimator stretchAnim2 = ObjectAnimator.ofFloat(newBall, "height", newBall.getHeight(), newBall.getHeight() - 25); stretchAnim2.setDuration(duration / 4); stretchAnim2.setRepeatCount(1); stretchAnim2.setInterpolator(new DecelerateInterpolator()); stretchAnim2.setRepeatMode(ValueAnimator.REVERSE); ValueAnimator bounceBackAnim = ObjectAnimator.ofFloat(newBall, "y", endY, startY); bounceBackAnim.setDuration(duration); bounceBackAnim.setInterpolator(new DecelerateInterpolator()); // Sequence the down/squash&stretch/up animations AnimatorSet bouncer = new AnimatorSet(); bouncer.play(bounceAnim).before(squashAnim1); bouncer.play(squashAnim1).with(squashAnim2); bouncer.play(squashAnim1).with(stretchAnim1); bouncer.play(squashAnim1).with(stretchAnim2); bouncer.play(bounceBackAnim).after(stretchAnim2); // Fading animation - remove the ball when the animation is done ValueAnimator fadeAnim = ObjectAnimator.ofFloat(newBall, "alpha", 1f, 0f); fadeAnim.setDuration(250); fadeAnim.addListener( new AnimatorListenerAdapter() { @Override public void onAnimationEnd(Animator animation) { balls.remove(((ObjectAnimator) animation).getTarget()); } }); // Sequence the two animations to play one after the other AnimatorSet animatorSet = new AnimatorSet(); animatorSet.play(bouncer).before(fadeAnim); // Start the animation animatorSet.start(); return true; }