Android用Animation实现图像的 渐变、缩放、位移、旋转

? Android 平台提供了两类动画。 一类是Tween动画，就是对场景里的对象不断的进行图像变化来产生动画效果（旋转、平移、放缩和渐变）。 二.RotateAnimation

    <?xml version="1.0" encoding="utf-8"?>  
    <AbsoluteLayout  
        android:layout_width="fill_parent"  
        android:layout_height="fill_parent"  
        xmlns:android="http://schemas.android.com/apk/res/android">  
    <Button  
        android:id="@+id/button_scale"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:text="scale"  
        android:layout_x="5dp"  
        android:layout_y="383dp" />  
    <Button  
        android:id="@+id/button_rotate"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:text="rotate"  
        android:layout_x="158dp"  
        android:layout_y="383dp" />  
    <Button  
        android:id="@+id/button_alpha"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:text="alpha"  
        android:layout_x="5dp"  
        android:layout_y="331dp" />  
    <Button  
        android:id="@+id/button_translate"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:text="translate"  
        android:layout_x="160dp"  
        android:layout_y="329dp" />  
    <Button  
        android:id="@+id/button_alpha_translate"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:text="alpha_translate"  
        android:layout_x="84dp"  
        android:layout_y="265dp" />  
      
    <ImageView  
        android:id="@+id/imageview"  
        android:layout_width="wrap_content"  
        android:layout_height="wrap_content"  
        android:layout_x="105dp"  
        android:layout_y="133dp"   
        android:src="@drawable/ic_launcher"  
        />  
    </AbsoluteLayout>  

实现本实例的源代码如下：

    public class Animations_Activity extends Activity {  
        private Button button1;  
        private Button button2;  
        private Button button3;  
        private Button button4;  
        private Button button5;  
        private ImageView imageView;  
      
        @Override  
        protected void onCreate(Bundle savedInstanceState) {  
            super.onCreate(savedInstanceState);  
            setContentView(R.layout.activity_animations_);  
            button1=(Button)findViewById(R.id.button_alpha);  
            button2=(Button)findViewById(R.id.button_rotate);  
            button3=(Button)findViewById(R.id.button_scale);  
            button4=(Button)findViewById(R.id.button_translate);  
            button5=(Button)findViewById(R.id.button_alpha_translate);  
            imageView=(ImageView)findViewById(R.id.imageview);  
            button1.setOnClickListener(new MyButton());  
            button2.setOnClickListener(new MyButton());  
            button3.setOnClickListener(new MyButton());  
            button4.setOnClickListener(new MyButton());  
            button5.setOnClickListener(new MyButton());  
        }  
        class MyButton implements OnClickListener{  
      
            @Override  
            public void onClick(View arg0) {  
                // TODO Auto-generated method stub  
                switch (arg0.getId()) {  
                case R.id.button_alpha:  
                    Alpha();  
                    break;  
                case R.id.button_rotate:  
                    Rotata();  
                    break;  
                case R.id.button_scale:  
                    Scale();  
                    break;  
                case R.id.button_translate:  
                    Translate();  
                    break;  
                case R.id.button_alpha_translate:  
                    Alpha_Translate();  
                    break;  
      
                default:  
                    break;  
                }  
            }  
              
        }  
          
        /* 
         * 1.创建一个AnimationSet对象，该对象存储的是动画的集合 
         * 2.根据需要创建相应的Animation对象 
         * 3.根据动画的需求，为Animation对象设置相应的数据（即执行效果） 
         * 4.奖Animation对象添加到AnimationSet对象当中 
         * 5.使用控件对象开始执行AnimationSet 
         */  
        public void Alpha() {  
            AnimationSet animationSet=new AnimationSet(true);  
            AlphaAnimation alphaAnimation=new AlphaAnimation(1,0);  
            alphaAnimation.setDuration(2000);  
            animationSet.addAnimation(alphaAnimation);  
            imageView.startAnimation(animationSet);  
        }  
        public void Rotata(){  
            AnimationSet animationSet=new AnimationSet(true);  
            //后面的四个参数定义的是旋转的圆心位置  
            RotateAnimation rotateAnimation=new RotateAnimation(  
                    0,360,Animation.RELATIVE_TO_PARENT,1f,0f);  
            rotateAnimation.setDuration(2000);  
            animationSet.addAnimation(rotateAnimation);  
            imageView.startAnimation(animationSet);  
        }  
        public void Scale() {  
            AnimationSet animationSet=new AnimationSet(true);  
            ScaleAnimation scaleAnimation=new ScaleAnimation(  
                    1,0.1f,1,Animation.RELATIVE_TO_SELF,0.5f,0.5f);  
            scaleAnimation.setDuration(2000);  
            animationSet.addAnimation(scaleAnimation);  
            imageView.startAnimation(scaleAnimation);  
        }  
        public void Translate() {  
            AnimationSet animationSet=new AnimationSet(true);  
            TranslateAnimation translateAnimation=new TranslateAnimation(  
                    Animation.RELATIVE_TO_SELF,0f,//X轴的开始位置  
                    Animation.RELATIVE_TO_SELF,//X轴的结束位置  
                    Animation.RELATIVE_TO_SELF,//Y轴的开始位置  
                    Animation.RELATIVE_TO_SELF,1.0f);  //Y轴的结束位置  
            translateAnimation.setDuration(2000);  
            animationSet.addAnimation(translateAnimation);  
              
            /* 
             * 第一行的设置如果为true，则动画执行完之后效果定格在执行完之后的状态 
             * 第二行的设置如果为false，则动画执行完之后效果定格在执行完之后的状态 
             * 第三行设置的是一个long类型的值，是指动画延迟多少毫秒之后执行 
             * 第四行定义的是动画重复几次执行 
             */  
            animationSet.setFillAfter(true);  
            animationSet.setFillBefore(false);  
            animationSet.setStartOffset(2000);  
            animationSet.setRepeatCount(3);  
              
            imageView.startAnimation(animationSet);  
        }  
        public void Alpha_Translate() {  
            AnimationSet animationSet=new AnimationSet(true);  
            AlphaAnimation alphaAnimation=new AlphaAnimation(1,0);  
            alphaAnimation.setDuration(2000);  
            animationSet.addAnimation(alphaAnimation);  
            TranslateAnimation translateAnimation=new TranslateAnimation(  
                    Animation.RELATIVE_TO_SELF,1.0f);  //Y轴的结束位置  
            translateAnimation.setDuration(2000);  
            animationSet.addAnimation(translateAnimation);  
            imageView.startAnimation(animationSet);  
        }  
      
        @Override  
        public boolean onCreateOptionsMenu(Menu menu) {  
            // Inflate the menu; this adds items to the action bar if it is present.  
            getMenuInflater().inflate(R.menu.activity_animations_,menu);  
            return true;  
        }  
      
    }