Question

我正在开展一个项目，要求我同时为2个视图制作动画。

状态0： 2个观看次数位于圈子的x1 = -Radius, y1 = 0 / x2 = Radius, y2 = 0。

状态1：他们应该同时移动到圆圈的顶部中心并发生碰撞（如钟摆）

状态2：他们应该同时回到圆圈的底部中心并且也会碰撞

状态3 .. N：他们应该到顶部中心碰撞然后再回到底部中心并再次碰撞......

我尝试了多个库，包括ArcAnimator，但似乎没有人支持这个。

有没有办法做到这一点？仅通过XML或以编程方式并不重要。

编辑：

这是我到目前为止所做的：

private void startAnimation () {

    DisplayMetrics metrics = new DisplayMetrics();
    getWindowManager ().getDefaultDisplay ().getMetrics (metrics);

    int width   = metrics.widthPixels;
    int height  = metrics.heightPixels;
    float scale = metrics.density;

    float initLeftX         = leftBall.getX ();
    float initLeftY         = leftBall.getY ();
    float targetLeftX       = topHelperView.getX (); // helper view on top of circle.
    float targetLeftY       = topHelperView.getY (); 

    float initRightX        = rightBall.getX ();
    float initRightY        = rightBall.getY ();
    float targetRightX      = topHelperView.getX ();
    float targetRightY      = topHelperView.getY ();

    AnimatorSet animSet     = new AnimatorSet ();

    ObjectAnimator anim1    = ObjectAnimator.ofFloat (leftBall, "x", initLeftX, targetLeftX);
    ObjectAnimator anim2    = ObjectAnimator.ofFloat (leftBall, "y", initLeftY, targetLeftY);
    ObjectAnimator anim3    = ObjectAnimator.ofFloat (rightBall, "x", initRightX, targetRightX);
    ObjectAnimator anim4    = ObjectAnimator.ofFloat (rightBall, "y", initRightY, targetRightY);

    animSet.play (anim1).with (anim2).with (anim3).with (anim4);

    animSet.setDuration (5000);
    animSet.start ();

}

然而问题是动画线性地进行并且不跟随外圆的弯曲路径。我无法想到任何实现钟摆碰撞的概念。

Answer 1

此示例代码需要进行一些调整，但我相信它会对您有所帮助：

package com.pachacuti.bouncingball;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.DisplayMetrics;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.AnimationSet;
import android.view.animation.RotateAnimation;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        DisplayMetrics displayMetrics = new DisplayMetrics();
        this.getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);
        int windowHeight = displayMetrics.heightPixels;
        int windowWidth =  displayMetrics.widthPixels;

        final RotateAnimation rAnimLeft1 = new RotateAnimation(0, 90,
                Animation.ABSOLUTE, windowWidth/2, Animation.ABSOLUTE, 0);
        rAnimLeft1.setDuration(4000);

        final RotateAnimation rAnimLeft2 = new RotateAnimation(0, -180,
                Animation.ABSOLUTE, windowWidth/2, Animation.ABSOLUTE, 0);
        rAnimLeft2.setDuration(4000);
        rAnimLeft2.setRepeatCount(-1);
        rAnimLeft2.setRepeatMode(2);

        final RotateAnimation rAnimRight1 = new RotateAnimation(0, -90,
                Animation.ABSOLUTE, -windowWidth/2, Animation.ABSOLUTE, 0);
        rAnimRight1.setDuration(4000);

        final RotateAnimation rAnimRight2 = new RotateAnimation(0, 180,
                Animation.ABSOLUTE, -windowWidth/2, Animation.ABSOLUTE, 0);
        rAnimRight2.setDuration(4000);
        rAnimRight2.setRepeatCount(-1);
        rAnimRight2.setRepeatMode(2);

        final View bleft = findViewById(R.id.bLeft);
        AnimationSet animSetLeft = new AnimationSet(true);
        animSetLeft.addAnimation(rAnimLeft1);
        animSetLeft.addAnimation(rAnimLeft2);
        bleft.startAnimation(animSetLeft);

        final View bright = findViewById(R.id.bRight);
        AnimationSet animSetRight = new AnimationSet(true);
        animSetRight.addAnimation(rAnimRight1);
        animSetRight.addAnimation(rAnimRight2);
        bright.startAnimation(animSetRight);
    }

}

布局文件：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.moahh.bouncingball.MainActivity">

    <View
        android:id="@+id/bLeft"
        android:layout_width="10px"
        android:layout_height="10px"
        android:background="@color/colorAccent"
        android:layout_centerVertical="true"
        android:layout_alignParentLeft="true"
         />

    <View
        android:id="@+id/bRight"
        android:layout_width="10px"
        android:layout_height="10px"
        android:background="@color/colorAccent"
        android:layout_centerVertical="true"
        android:layout_alignParentRight="true"
        />
</RelativeLayout>

无限动画的2个视图跟随夸脱/半圈

1 个答案: