解决Android帧动画在Oncreate中启动只显示第一帧 和 Android中获取设备的IP

http://berdy.iteye.com/blog/1894802

做了个简单的帧动画，在onCreate方法中start，发现只能看到第一帧 

 <?xml version="1.0" encoding="utf-8"?>
 <animation-list xmlns:android="http://schemas.android.com/apk/res/android"
     android:oneshot="false" >

     <item
         android:drawable="@drawable/fire01"
         android:duration="200"/>
     <item
         android:drawable="@drawable/fire02"
         android:duration="200"/>
     <item
         android:drawable="@drawable/fire03"
         android:duration="200"/>
     <item
         android:drawable="@drawable/fire04"
         android:duration="200"/>
     <item
         android:drawable="@drawable/fire05"
         android:duration="200"/>
     <item
         android:drawable="@drawable/fire06"
         android:duration="200"/>
     <item
         android:drawable="@drawable/fire07"
         android:duration="200"/>
     <item
         android:drawable="@drawable/fire08"
         android:duration="200"/>
     <item
         android:drawable="@drawable/fire09"
         android:duration="200"/>

 </animation-list>

 <RelativeLayout 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"
     >
     <ImageView
         android:id="@+id/fire_img"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_centerInParent="true"
         android:background="@drawable/fire_anim" />
 </RelativeLayout>

 ImageView fireImg = null;

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

     ImageView fireImg = (ImageView) findViewById(R.id.fire_img);
     final AnimationDrawable animDrawable = (AnimationDrawable) fireImg
             .getBackground();
     animDrawable.start();
 }

stackoverflow 上发现一个解决办法 

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

     ImageView fireImg = (ImageView) findViewById(R.id.fire_img);
     final AnimationDrawable animDrawable = (AnimationDrawable) fireImg
             .getBackground();
     fireImg.post(new Runnable() {
         @Override
         public void run() {
             animDrawable.start();
         }
     });
 }

或者在Activity中的onWindowFocusChanged方法中start 

 @Override
 public void onWindowFocusChanged(boolean hasFocus) {
     super.onWindowFocusChanged(hasFocus);
     if (fireImg != null) {
         AnimationDrawable animDrawable = (AnimationDrawable) fireImg
                 .getBackground();
         animDrawable.start();
     }
 }

在wifi环境下，可以通过WifiInfo来获取设备的ip 

 public String getIpAddress() {
     WifiManager wifiManager = (WifiManager) getSystemService(WIFI_SERVICE);
     WifiInfo wifiInfo = wifiManager.getConnectionInfo();
     int ipAddress = wifiInfo.getIpAddress();
     int[] ipAddr = new int[4];
     ipAddr[0] = ipAddress & 0xFF;
     ipAddr[1] = (ipAddress >> 8) & 0xFF;
     ipAddr[2] = (ipAddress >> 16) & 0xFF;
     ipAddr[3] = (ipAddress >> 24) & 0xFF;
     return new StringBuilder().append(ipAddr[0]).append(".").append(ipAddr[1]).append(".").append(ipAddr[2])
             .append(".").append(ipAddr[3]).append(".").toString();

 }

执行上面的代码需要 

 <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />

当然也可通过jdk总的NetworkInterface来获取的，就是遍历所有的网络接口，获取到非loopback ip 

 public String getLocalIpAddress() {
     try {
         for (Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces(); en.hasMoreElements();) {
             NetworkInterface intf = en.nextElement();
             for (Enumeration<InetAddress> enumIpAddr = intf.getInetAddresses(); enumIpAddr.hasMoreElements();) {
                 InetAddress inetAddress = enumIpAddr.nextElement();
                 if (!inetAddress.isLoopbackAddress()) {
                     return inetAddress.getHostAddress().toString();
                 }
             }
         }
     } catch (SocketException ex) {
         Log.e("", ex.toString());
     }
     return null;
 }