android通过xml文件实现Animation动画

Rotate的xml文件编写方法

    <rotate
        android:fromDegrees="0"
        android:toDegrees="+350"
        android:pivotX="50%"
        android:pivotY="50%"
        android:duration="1000"/>

*android:toDegrees="+350"正号代表的是旋转方向，正号为顺时针，负号为逆时针

*android:pivotX的值共有三种设置方法

1.android:pivotX="50"这种方法使用绝对位置定位(屏幕位置坐标上50这个点)

2.android:pivotX="50%"这种方法使用相对于控件本身定位

3.android:pivotX="50%p"这种方法相对于控件的父控件定位

其他几种动画的写法与此类似

MainActivity.java

public class MainActivity extends Activity {

    private ImageView imageView;
    private Button button_1;
    private Button button_2;
    private Button button_3;
    private Button button_4;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        imageView = (ImageView)findViewById(R.id.imageView);
        button_1 = (Button)findViewById(R.id.button_1);
        button_2 = (Button)findViewById(R.id.button_2);
        button_3 = (Button)findViewById(R.id.button_3);
        button_4 = (Button)findViewById(R.id.button_4);

        AlphaButtonListener alphaButtonListener = new AlphaButtonListener();
        RotateButtonListener rotateButtonListener = new RotateButtonListener();
        ScaleButtonListener scaleButtonListener = new ScaleButtonListener();
        TranslateButtonListener translateButtonListener = new TranslateButtonListener();

        button_1.setOnClickListener(alphaButtonListener);
        button_2.setOnClickListener(rotateButtonListener);
        button_3.setOnClickListener(scaleButtonListener);
        button_4.setOnClickListener(translateButtonListener);
    }
    //淡入淡出
    private class AlphaButtonListener implements OnClickListener {
        @Override
        public void onClick(View v) {
            //使用AnimationUtils装载动画文件
            Animation animation = AnimationUtils.loadAnimation(MainActivity.this, R.anim.alpha);
            imageView.startAnimation(animation);
        }
    }
    //旋转
    private class RotateButtonListener implements OnClickListener {
        @Override
        public void onClick(View v) {
            Animation animation = AnimationUtils.loadAnimation(MainActivity.this, R.anim.rotate);
            imageView.startAnimation(animation);
        }
    }
    //水平
    private class TranslateButtonListener implements OnClickListener {
        @Override
        public void onClick(View v) {
            Animation animation = AnimationUtils.loadAnimation(MainActivity.this, R.anim.translate);
            imageView.startAnimation(animation);
        }
    }
    //缩放
    private class ScaleButtonListener implements OnClickListener {
        @Override
        public void onClick(View v) {
            Animation animation = AnimationUtils.loadAnimation(MainActivity.this, R.anim.scale);
            imageView.startAnimation(animation);
        }
    }

}

在res目录下新建anim文件夹

alpha.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
    android:interpolator="@android:anim/accelerate_interpolator">

    <alpha
        android:fromAlpha="1.0"
        android:toAlpha="0.0"
        android:startOffset="500"
        android:duration="500"/>

</set>

rotate.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
    android:interpolator="@android:anim/accelerate_interpolator">

    <rotate
        android:fromDegrees="0"
        android:toDegrees="360"
        android:pivotX="50%"
        android:pivotY="50%"
        android:duration="3000"/>

</set>

scale.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <scale
        android:fromXScale="1.0"
        android:toXScale="0.0"
        android:fromYScale="1.0"
        android:toYScale="0.0"
        android:pivotX="50%"
        android:pivotY="50%"
        android:duration="1000"/>

</set>

translate.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
    android:interpolator="@android:anim/accelerate_interpolator">

    <translate
        android:fromXDelta="50%"
        android:toXDelta="100%"
        android:fromYDelta="50%"
        android:toYDelta="100%"
        android:duration="1000"/>

</set>