Android Drawable Animation 学习

Drawable Animation（Frame Animation） Drawable Animation（Frame Animation）：帧动画，就像GIF图片，通过一系列Drawable依次显示来模拟动画的效果。在XML中的定义方式如下：

<?xml version="1.0" encoding="utf-8"?>
<animation-list android:oneshot="false"
  xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:duration="400" android:drawable="@drawable/send_loading1" />
    <item android:duration="400" android:drawable="@drawable/send_loading2" />
    <item android:duration="400" android:drawable="@drawable/send_loading3" />
    <item android:duration="400" android:drawable="@drawable/send_loading4" />
    <item android:duration="400" android:drawable="@drawable/send_loading5" />
    <item android:duration="400" android:drawable="@drawable/send_loading1" />
</animation-list>

下面通过一个例子演示其作用

目录结构

common_loading_animation.xml

<?xml version="1.0" encoding="utf-8"?>
<animation-list android:oneshot="false"
  xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:duration="400" android:drawable="@drawable/send_loading1" />
    <item android:duration="400" android:drawable="@drawable/send_loading2" />
    <item android:duration="400" android:drawable="@drawable/send_loading3" />
    <item android:duration="400" android:drawable="@drawable/send_loading4" />
    <item android:duration="400" android:drawable="@drawable/send_loading5" />
    <item android:duration="400" android:drawable="@drawable/send_loading1" />
</animation-list>

horizontal_loading_animation.xml

<?xml version="1.0" encoding="utf-8"?>
<animation-list android:oneshot="false"
  xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo1" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo2" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo3" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo4" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo4" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo5" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo6" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo7" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo8" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo9" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo10" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo11" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo12" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo13" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo14" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo15" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo16" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo17" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo18" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo19" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo20" />
    <item android:duration="400" android:drawable="@drawable/progressbar_indeterminate_holo21" />
</animation-list>

activity_main.xml

<LinearLayout 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:orientation="vertical"
    tools:context=".MainActivity" >

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp" >

        <ProgressBar
            android:layout_width="match_parent"
            android:layout_height="2dp"
            android:indeterminateDrawable="@drawable/horizontal_loading_animation" />
    </RelativeLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:orientation="vertical" >

        <ImageView
            android:id="@+id/iv"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" 
            android:contentDescription="@string/app_name"
            />
        
        <Button 
            android:id="@+id/bt_start"
            android:layout_marginTop="10dp"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="开始"
            />
        
    </LinearLayout>

</LinearLayout>

MainActivity.java

package com.example.loadingview;

import android.app.Activity;
import android.graphics.drawable.AnimationDrawable;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;

public class MainActivity extends Activity {

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

		findView();
	}

	private void findView() {

		ImageView rocketImage = (ImageView) findViewById(R.id.iv);
		rocketImage.setBackgroundResource(R.drawable.common_loading_animation);
		
		final AnimationDrawable rocketAnimation = (AnimationDrawable) rocketImage
				.getBackground();

		Button bt_start = (Button) findViewById(R.id.bt_start);
		bt_start.setOnClickListener(new OnClickListener() {

			@Override
			public void onClick(View v) {
				
				rocketAnimation.start();
//				rocketAnimation.stop();	//停止
			}
		});
	}

}

详细可参考：http://developer.android.com/guide/topics/graphics/drawable-animation.html