Question

In my android, I want to show a message box with no way to quit it, and while its showing, another process needs to run (in my case an email sending function). Then after the email is finished sending, the alert box needs to close.

This is what i got so far, but it’s not working…

Can anyone help?

    AlertDialog.Builder alertDialog = new Builder(this); // create an alert box
    alertDialog.setTitle("Sending...");
    alertDialog.setMessage("Please wait while your details and image is being sent to x.");

    alertDialog.show(); // show the alert box
    Reusable_CodeActivity.send_email(gmailAC, gmpassword, get_all_details(), image_path, this);

    alertDialog.setPositiveButton("OK", new DialogInterface.OnClickListener() { // define the 'OK' button
        public void onClick(DialogInterface dialog, int which) {
            dialog.cancel();
        } 
    });

Answer 1

I’m not sure about the email-sending part, but I can help you make the message box like you want to.

If you remove the following code:

alertDialog.setPositiveButton("OK", new DialogInterface.OnClickListener() { // define the 'OK' button
    public void onClick(DialogInterface dialog, int which) {
        dialog.cancel();
    } 
});

Then the dialog will display with no buttons, and if you add .setCancelable(false) it will not be dismissed until you tell it to, using alertDialog.cancel();

Here’s an example (modified from one of my dialogs):

AlertDialog.Builder builder = new AlertDialog.Builder(this); // Create the dialog object
        builder.setMessage(R.string.dialog_disclaimer_text)  // I use a reference to a string resource - it's good practice instead of using hardcoded text
               .setIcon(android.R.drawable.ic_dialog_info)   // Here I specify an icon to be displayed in the top corner
               .setTitle(R.string.dialog_disclaimer_title)
               .setCancelable(false) // This one makes the dialog stay until the dismiss is called

               .create().show(); // Show the dialog

This code will display a dialog with text, which will not disappear until the activity calls builder.dismiss(); – which you’d then have to implement in some sort of a listener, or callback once the sending is complete.

Update

Looking at the other answer, this is probably how your code should look like (thanks to iturki)

private class SendEmailTask extends AsyncTask<Void, Void, Void> {  
    AlertDialog.Builder alertDialog; // Define the AlertDialog builder object so it can be used/adressed across the entire class

    protected void onPreExecute() {
       //Show the dialog first
       alertDialog = new Builder(context);
       alertDialog.setTitle("Sending...")
                  .setMessage("Please wait while your details and image is being sent to x.");
                  .setCancelable(false)
                  .show();
    }
    protected void doInBackground(Void... params) {
       //Send Email Code
       Reusable_CodeActivity.send_email(gmailAC, gmpassword, get_all_details(), image_path, this);
    }

    protected void onPostExecute(Void result) {
       //Dismiss the dialog 
       alertDialog.dismiss();
    }
}