Android 自定义帧动画

Android L ； Android Studio

帧动画

和gif图片类似，顺序播放准本好的图片文件；图片资源在xml文件中配置好

Android 帧动画例子

可以把动画放进子线程中启动，也可以在主线程直接启动动画

主线程的UI不能放进子线程去设置；即子线程不能直接修改主UI；

动画资源

图片资源来自Android L Launcher3 res

配置文件 transition_stack.xml

         
          
      ......
     

Java代码

• 1.取得ImageView
• 2.为ImageView设置背景资源文件

• 3.把ImageView的背景赋给动画AnimationDrawable

  public class MainActivity extends AppCompatActivity {private ImageView mTransitionIcon;private ImageView mStackIcon;private AnimationDrawable frameAnimation;private AnimationDrawable stackAnimation;private Thread stackThread;private Button stopButton;public boolean action = false;private TextView tvState;@Overrideprotected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);    setSupportActionBar(toolbar);    tvState = (TextView) findViewById(R.id.tv_state);    stopButton = (Button) findViewById(R.id.btn_stop);    Button btn1 = (Button) findViewById(R.id.btn1);    Button btn2 = (Button) findViewById(R.id.btn2);    /*************************************************     * AnimationDrawable extends DrawableContainer     *************************************************/     // 1.取得ImageView    mTransitionIcon = (ImageView) findViewById(R.id.settings_transition_image);    // 2.为ImageView设置背景资源文件    mTransitionIcon.setBackgroundResource(R.drawable.transition_none);    // 3.把ImageView的背景赋给动画AnimationDrawable    frameAnimation = (AnimationDrawable) mTransitionIcon.getBackground();    mStackIcon = (ImageView) findViewById(R.id.transition_stack);    mStackIcon.setBackgroundResource(R.drawable.transition_stack);    stackAnimation = (AnimationDrawable) mStackIcon.getBackground();    stackThread = new Thread() {        @Override        public void run() {            stackAnimation.start();// 子线程中开始动画        }    };    btn1.setOnClickListener(new View.OnClickListener() {        @Override        public void onClick(View v) {            action = !action;// 主线程中控制动画启动与停止            if (action) {                frameAnimation.start(); // 启动（重启）动画            } else {                frameAnimation.stop(); // 停止动画            }        }    });    btn2.setOnClickListener(new View.OnClickListener() {        @Override        public void onClick(View v) {            if (stackThread.getState() == (Thread.State.NEW))                stackThread.start();// 放到子线程中开启动画        }// 先查询子线程状态再启动，避免Thread报错导致app退出    });    stopButton.setOnClickListener(new View.OnClickListener() {        @Override        public void onClick(View v) {            String s = "";// 用于显示状态            s = action ? "action! " + stackThread.getState().toString() :                    "stop!" + stackThread.getState().toString();            tvState.setText(s);        }    });}}

  Thread 类

  状态一览：

  /** * A representation of a thread's state. A given thread may only be in one * state at a time. */public enum State {    /**     * The thread has been created, but has never been started.     */    NEW,    /**     * The thread may be run.     */    RUNNABLE,    /**     * The thread is blocked and waiting for a lock.     */    BLOCKED,    /**     * The thread is waiting.     */    WAITING,    /**     * The thread is waiting for a specified amount of time.     */    TIMED_WAITING,    /**     * The thread has been terminated.     */    TERMINATED}

  一个Button用于启动子线程，可以先判断子线程的状态，再决定是否启动