消息：如果没有连接，请在恢复时发送消息

Question

I have created an instant messaging app for Android. But now I want to add some functionality:

If the users have not internet connection at the moment they try to send the message, it will have to be sent when the users recover the connection.

I guess the best way to do it is with a broadcast receiver. But I am not sure.

Answer 1

EDIT: You could keep track of all the fail requests once the connection fails and set a thread who runs in the background that tries to send the failed messages. Let's say every 10-20 seconds or more. And if fails the thread goes to sleep. Once all the messages are sent you close the thread and a new thread starts only if a message fails. if another message fails you check int he Queue. You could also use of PriorityQueue to schedule the messages in a easier way

You can Get the Network State like this.

 public boolean getInternetState() {

   ConnectivityManager conMgr =  (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
   NetworkInfo activeNetwork = conMgr.getActiveNetworkInfo();

    if (activeNetwork != null && activeNetwork.isConnected()) {
        return true;
    } else {
        DialogFragment noInternet = new NoInternetDialog();
        noInternet.show(getFragmentManager(), "noInternet");
        return false;
    }
}

And the you can show a DialogFragment to the user which will take him to wifi-settings or wherever you want.

public class NoInternetDialog extends DialogFragment {

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    // Use the Builder class for convenient dialog construction
    AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
    builder.setMessage("No Internet Connection! Please Check your Internet Connection and try Again!")
            .setPositiveButton("Open Wi-fi Settings", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int id) {
                    startActivity(new Intent(WifiManager.ACTION_PICK_WIFI_NETWORK));
                }
            })
            .setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int id) {
                    // User cancelled the dialog
                }
            });
    // Create the AlertDialog object and return it
    return builder.create();
}

}

if(getInternetState()) {
      // do network request here
}