檢查數據連接

Question

我有一個onclick事件按鈕，打開另一個類。另一類正在進行網絡調用以檢索數據，因此如果沒有連接，則應用程序部隊將關閉。

我該如何實現一個try catch或if語句來檢查數據連接，如果沒有，則顯示吐司這樣說。如果有，然後進入第二課。

Answer 1

我使用：在您的Android清單

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

：

public boolean isOnline() { 
    ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE); 
    NetworkInfo netInfo = cm.getActiveNetworkInfo(); 
    if (netInfo != null && netInfo.isConnectedOrConnecting()) { 
     return true; 
    } 
    return false; 
} 

Answer 2

做這樣的事情，檢查互聯網連接：

static public boolean isInternetActive() 
{ 
    ConnectivityManager connectivity = (ConnectivityManager) getApplicationContext().getSystemService(Context.CONNECTIVITY_SERVICE); 

    NetworkInfo info = (NetworkInfo) connectivity.getActiveNetworkInfo(); 

    if (info == null || !info.isConnected()) 
    { 
     return false; 
    } 
    if (info.isRoaming()) 
    { 
     return false; 
    } 
    return true; 
} 

Answer 3

public boolean isOnline() { 
ConnectivityManager cm = 
    (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE); 

return cm.getActiveNetworkInfo() != null && 
    cm.getActiveNetworkInfo().isConnectedOrConnecting(); 
} 

你也需要。

Answer 4

這段代碼檢查是否是互聯網連接開啓或關閉的代碼檢查wifi和電話網。

public boolean CheckInternet() 
{ 
    ConnectivityManager connec = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE); 
android.net.NetworkInfo wifi = connec.getNetworkInfo(ConnectivityManager.TYPE_WIFI); 

    android.net.NetworkInfo mobile = connec.getNetworkInfo(ConnectivityManager.TYPE_MOBILE); 

    // Here if condition check for wifi and mobile network is available or not. 
    // If anyone of them is available or connected then it will return true, otherwise false; 

    if (wifi.isConnected()) { 
     return true; 
    } else if (mobile.isConnected()) { 
     return true; 
    } 
    return false; 
} 

清單文件::

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

Answer 5

試試這個，這將幫助你..

public class CheckNetworkInfo { 

    public static boolean haveNetworkConnection(Context context) { 

     ConnectivityManager cm = (ConnectivityManager) context 
        .getSystemService(Context.CONNECTIVITY_SERVICE); 
      // test for connection 
      if (cm.getActiveNetworkInfo() != null 
        && cm.getActiveNetworkInfo().isAvailable() 
        && cm.getActiveNetworkInfo().isConnected()) { 
       Log.v("Yeah", "Internet is working"); 
       // txt_status.setText("Internet is working"); 
       return true; 
      } else { 
       // txt_status.setText("Internet Connection Not Present"); 
       Log.v("Sorry", "Internet Connection Not Present"); 
       return false; 
      } 
} 

//調用上面類的靜態方法，其中u要檢查網絡可用性

class Myactivity extends Activity{ 

public void onCreate(Bundle savedInstanceState) { 

    if(CheckNetworkInfo.haveNetworkConnection(Myactivity.this)){ 
      startActivity(new Intent(HomePage.this,SearchTerm.class)); 
     } 
     else{ 
      AlertDialog.Builder a=new AlertDialog.Builder(Myactivity.this); 
      a.setTitle("Check Network Connection"); 
      a.setPositiveButton("OK",new android.content.DialogInterface.OnClickListener() { 

       @Override 
       public void onClick(DialogInterface dialog, int which) { 
        // TODO Auto-generated method stub 
       dialog.dismiss(); 
       } 
      }); 
      a.show(); 
     } 
} 
} 

Answer 6

只需使用它。

從任何地方調用此代碼，它會返回您當前的網絡狀態。

public static boolean isInternetAvailable(Context c) 
    { 
     ConnectivityManager connectivityManager 
     = (ConnectivityManager) c.getSystemService(Context.CONNECTIVITY_SERVICE); 
     NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo(); 
     return activeNetworkInfo != null && activeNetworkInfo.getState() == NetworkInfo.State.CONNECTED; 
    } 

如果連接則返回true，否則返回false。對其輸出採取任何所需的操作。

注意：它是一種靜態方法。因此，如果您只想從Android Activity類中調用它，請移除static關鍵字。