Android：捕捉異常，如果移動數據未啓用

Question

目前我的應用程序崩潰，如果沒有啓用互聯網。我想知道如何捕捉異常，並顯示我的popupdialog（下面），以便他們可以導航以重新打開數據。我檢查這樣的電話狀態：

public void CheckInternet() 
{ 
    ConnectivityManager connec = (ConnectivityManager) this.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()) { 

    } else if (!mobile.isConnected()) { 
     AlertDialog.Builder builder = new AlertDialog.Builder(this); 
     builder.setMessage("You need to enable mobile data in order to use this application:") 
       .setCancelable(false) 
       .setPositiveButton("Turn on Data", new DialogInterface.OnClickListener() { 
        public void onClick(DialogInterface dialog, int id) { 
         dialog.cancel(); 
         Intent newintent = new Intent(android.provider.Settings.ACTION_WIRELESS_SETTINGS); 
         startActivity(newintent); 


        } 
       }) 
       .setNegativeButton("Exit", new DialogInterface.OnClickListener() { 
        public void onClick(DialogInterface dialog, int id) { 
         Main.this.finish(); 
        } 
       }); 
     AlertDialog alert = builder.show(); 
    } else if (mobile.isConnected()) { 
     //nothing 
    } 
} 

而我在onCreate（）的開頭調用函數。

在此先感謝！

Answer 1

您可以創建這個布爾方法，並調用它時，你需要做一些事情需要網絡連接：

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

而且例子可能是以下幾點：

if (isOnline()) { 
    // Do network stuff 
} else { 
    // Show network error 
}