Android 检测网络连接状态

Android连接网络的时候,并不是每次都能连接到网络,因此在程序启动中需要对网络的状态进行判断,如果没有网络则提醒用户进行设置。

首先,要判断网络状态,需要有相应的权限,下面为权限代码(AndroidManifest.xml):

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

然后,检测网络状态是否可用

/** 
 * 对网络连接状态进行判断 
 * @return  true, 可用; false, 不可用 
 */  
private boolean isOpenNetwork() {  
   ConnectivityManager connManager = (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);  
   if(connManager.getActiveNetworkInfo() != null) {  
   return connManager.getActiveNetworkInfo().isAvailable();  
   }  
  
   return false;  
}  

最后,不可用则打开网络设置

/** 
 * 访问百度主页,网络不可用则需设置 
 */  
private void initMoreGames() {  
   String URL_MOREGAMES = "http://www.baidu.com";  
   mWebView = (WebView) findViewById(R.id.view_gamesort);  
  
   if (mWebView != null) {  
   mWebView.requestFocus();  
   WebSettings webSettings = mWebView.getSettings();  
   if (webSettings != null) {  
   webSettings.setJavaScriptEnabled(true);  
   webSettings.setCacheMode(MODE_PRIVATE);  
   webSettings.setDefaultTextEncodingName("utf-8");  
   }  
  
   // 判断网络是否可用  
   if(isOpenNetwork() == true) {  
   mWebView.loadUrl(URL_MOREGAMES);  
   } else {  
   AlertDialog.Builder builder = new AlertDialog.Builder(MoreGamesActivity.this);  
   builder.setTitle("没有可用的网络").setMessage("是否对网络进行设置?");  
   
   builder.setPositiveButton("是", new DialogInterface.OnClickListener() {  
   @Override  
   public void onClick(DialogInterface dialog, int which) {  
   Intent intent = null;  
   
   try {  
   String sdkVersion = android.os.Build.VERSION.SDK;  
   if(Integer.valueOf(sdkVersion) > 10) {  
   intent = new Intent(android.provider.Settings.ACTION_WIRELESS_SETTINGS);  
   }else {  
   intent = new Intent();  
   ComponentName comp = new ComponentName("com.android.settings", "com.android.settings.WirelessSettings");  
   intent.setComponent(comp);  
   intent.setAction("android.intent.action.VIEW");  
   }  
   MoreGamesActivity.this.startActivity(intent);  
   } catch (Exception e) {  
   Log.w(TAG, "open network settings failed, please check...");  
   e.printStackTrace();  
   }  
   }  
   }).setNegativeButton("否", new DialogInterface.OnClickListener() {  
   @Override  
   public void onClick(DialogInterface dialog, int which) {  
   dialog.cancel();          
   finish();  
   }  
   }).show();  
   }  
   } else {  
   Log.w(TAG, "mWebView is null, please check...");  
   }  
}