Android案例（属性动画）

1、实现效果

2、布局

donghua.xml

<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_marginBottom="5dp">      <ImageView android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/hcr" android:layout_centerInParent="true" android:id="@ id/pineapple"/>       <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_alignParentBottom="true">         <Button android:id="@ id/btn_one" android:layout_width="0dp" android:layout_height="wrap_content" android:layout_weight="1" android:text="渐变"/>
        <Button android:id="@+id/btn_two" android:layout_width="0dp" android:layout_height="wrap_content" android:layout_weight="1" android:text="旋转"/>
        <Button android:id="@+id/btn_three" android:layout_width="0dp" android:layout_height="wrap_content" android:layout_weight="1" android:text="缩放"/>
        <Button android:id="@+id/btn_four" android:layout_width="0dp" android:layout_height="wrap_content" android:layout_weight="1" android:text="移动" />
    </LinearLayout>


</RelativeLayout>

3、anim alpha_animation.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <alpha android:interpolator="@android:anim/linear_interpolator" android:repeatMode="reverse" android:repeatCount="infinite" android:duration="1000" android:fromAlpha="1.0" android:toAlpha="0.0"/>
</set>

rotate_animation.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <rotate android:fromDegrees="0" android:toDegrees="360" android:pivotX="50%" android:pivotY="50%" android:repeatMode="reverse" android:repeatCount="infinite" android:duration="1000"/>
</set>

scale_animation.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <scale android:fromXScale="1.0" android:fromYScale="1.0" android:toXScale="0.5" android:toYScale="0.5" android:pivotX="50%" android:pivotY="50%" android:repeatMode="reverse" android:repeatCount="infinite" android:duration="3000"/>
</set>

translate_animation.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <translate android:fromXDelta="0.0" android:fromYDelta="0.0" android:toXDelta="100" android:toYDelta="0.0" android:repeatCount="infinite" android:repeatMode="reverse" android:duration="4000"/>
</set>

4、java代码

package com.example.horse_run_application;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.Button;
import android.widget.ImageView;
import androidx.annotation.Nullable;

public class DonghuaActivity extends Activity implements View.OnClickListener{ 
       
    Button bt1,bt2,bt3,bt4;
    ImageView pineapple;
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) { 
       
        super.onCreate(savedInstanceState);
        setContentView(R.layout.donghua);//绑定布局

        bt1=(Button) findViewById(R.id.btn_one);           //绑定button
        bt2=(Button) findViewById(R.id.btn_two);
        bt3=(Button) findViewById(R.id.btn_three);
        bt4=(Button) findViewById(R.id.btn_four);

        pineapple=(ImageView)findViewById(R.id.pineapple);

        bt1.setOnClickListener(this);
        bt2.setOnClickListener(this);
        bt3.setOnClickListener(this);
        bt4.setOnClickListener(this);
    }

    @Override
    public void onClick(View view) { 
       
        switch (view.getId()){ 
       
            //渐变动画
            case R.id.btn_one:
                Animation alpha= AnimationUtils.loadAnimation(this,R.anim.alpha_animation);
                pineapple.startAnimation(alpha);
                break;
            //旋转动画
            case R.id.btn_two:
                Animation rotate=AnimationUtils.loadAnimation(this,R.anim.rotate_animation);
                pineapple.startAnimation(rotate);
                break;
            //缩放动画
            case R.id.btn_three:
                Animation scale=AnimationUtils.loadAnimation(this,R.anim.scale_animation);
                pineapple.startAnimation(scale);
                break;
            //平移动画
            case R.id.btn_four:
                Animation translate=AnimationUtils.loadAnimation(this,R.anim.translate_animation);
                pineapple.startAnimation(translate);
                break;
        }
    }
}