自定義View——抖音飄動紅心

效果展示

動畫效果
使用自定義view完成紅心飄動效果

View實現

動畫：屬性動畫（位移+縮放+透明度+旋轉）
+
隨機數：（屬性動畫參數+顏色選取）

View

/**
 * 飄心效果
 * 1.創建ImageView
 * 2.ImageView執行組合動畫
 * 3.動畫執行完成後銷燬View
 */
public class FlyHeartView extends RelativeLayout {

    private int defoutWidth = 200;//默認控件寬度
    private long mDuration = 3000;//默認動畫時間
    //顏色集合 從中獲取顏色
    private int[] color = {
            0xFFFF34B3, 0xFF9ACD32, 0xFF9400D3, 0xFFEE9A00,
            0xFFFFB6C1, 0xFFDA70D6, 0xFF8B008B, 0xFF4B0082,
            0xFF483D8B, 0xFF1E90FF, 0xFF00BFFF, 0xFF00FF7F
    };

    public FlyHeartView(Context context) {
        super(context);
        initFrameLayout();
    }

    public FlyHeartView(Context context, AttributeSet attrs) {
        super(context, attrs);
        initFrameLayout();
    }

    private void initFrameLayout() {
        ViewGroup.LayoutParams params = new ViewGroup.LayoutParams(defoutWidth, ViewGroup.LayoutParams.WRAP_CONTENT);
        setLayoutParams(params);
    }

    /**
     * 創建一個心形的view視圖
     */
    private ImageView createHeartView() {
        ImageView heartIv = new ImageView(getContext());
        LayoutParams params = new LayoutParams(defoutWidth / 2, defoutWidth / 2);

        //控件位置
        params.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM);
        params.addRule(RelativeLayout.CENTER_HORIZONTAL);

        heartIv.setLayoutParams(params);
        heartIv.setImageResource(R.mipmap.ic_heart);
        //改變顏色
        heartIv.setImageTintList(ColorStateList.valueOf(color[(int) (color.length * Math.random())]));
        return heartIv;
    }

    /**
     * 執行動畫
     * 在展示調用該方法
     */
    public void startFly() {
        final ImageView heartIv = createHeartView();
        addView(heartIv);
        AnimatorSet animatorSet = new AnimatorSet();
        animatorSet.play(createTranslationX(heartIv))
                .with(createTranslationY(heartIv))
                .with(createScale(heartIv))
                .with(createRotation(heartIv))
                .with(createAlpha(heartIv));
        //執行動畫
        animatorSet.start();
        //銷燬view
        animatorSet.addListener(new AnimatorListenerAdapter() {
            @Override
            public void onAnimationEnd(Animator animation) {
                super.onAnimationEnd(animation);
                removeView(heartIv);
            }
        });
    }

    /**
     * 橫向正弦位移動畫
     *
     * @return
     */
    private Animator createTranslationX(View view) {
        ObjectAnimator animator = ObjectAnimator.ofFloat(view, "translationX", 0, (float) (defoutWidth * Math.random() / 4));
        animator.setDuration(mDuration);
        //CycleInterpolator cycles 正弦曲線數
        animator.setInterpolator(new CycleInterpolator((float) (3 * Math.random())));
        return animator;
    }


    /**
     * 縱向加速位移動畫
     *
     * @return
     */
    private Animator createTranslationY(View view) {
        ObjectAnimator animator = ObjectAnimator.ofFloat(view, "translationY", 0, -1000);
        animator.setDuration(mDuration);
        animator.setInterpolator(new AccelerateInterpolator());
        return animator;
    }


    /**
     * 加速放大動畫
     *
     * @return
     */
    private Animator createScale(View view) {
        ObjectAnimator animatorX = ObjectAnimator.ofFloat(view, "scaleX", 1, 1.5f);
        ObjectAnimator animatorY = ObjectAnimator.ofFloat(view, "scaleY", 1, 1.5f);
        AnimatorSet animatorSet = new AnimatorSet();
        animatorSet.setDuration(mDuration);
        animatorSet.setInterpolator(new AccelerateInterpolator());
        animatorSet.play(animatorX).with(animatorY);
        return animatorSet;
    }

    /**
     * 透明度動畫
     *
     * @return
     */
    private Animator createAlpha(View view) {
        ObjectAnimator animator = ObjectAnimator.ofFloat(view, "alpha", 1, 0.1f);
        animator.setDuration(mDuration);
        animator.setInterpolator(new AccelerateInterpolator());
        return animator;
    }

    /**
     * 旋轉動畫
     *
     * @return
     */
    private Animator createRotation(View view) {
        ObjectAnimator animator = ObjectAnimator.ofFloat(view, "rotation", 0, (float) (25f * Math.random()));
        animator.setDuration(mDuration);
        animator.setInterpolator(new CycleInterpolator((float) (6 * Math.random())));
        return animator;
    }


}