Question

I have a public class which has some common generic functions, like e.g. for displaying dialogs in my application. I made a generic alertButtonDialog function and want to call it in activities whenever I’m using dialogs. I am very new to Java so please excuse me if it’s very basic.

public static class AlertDialogs{

    public static void alertButtonDialog(Activity activity, Context context, String title, String message, 
            String positiveButton, String negativeButton) {

        AlertDialog.Builder alertBuilder = new AlertDialog.Builder(context);
        alertBuilder.setTitle(title);
        alertBuilder.setMessage(message);
        alertBuilder.setPositiveButton(positiveButton, new OnClickListener() {

            public void onClick(DialogInterface dialog, int which) {
                Activity.this.finish(); // *?? How to do this part ??*
                // the activity to be finished is the activity which calls this function
            }
        })

    }
}

Later in any other activity, whenever I’m displaying a dialog, I would just do

 AlertDialogs.alertButtonDialog(...all my Strings...)

This is only for convenience accessing.

Answer 1

In your alertButtonDialog function, define the Activity activity argument as final. Then, from within the onClick listener invoke activity.finish();.

public static void alertButtonDialog(final Activity activity, Context context, String title, String message, 
        String positiveButton, String negativeButton) {

    AlertDialog.Builder alertBuilder = new AlertDialog.Builder(context);
    ...
    alertBuilder.setPositiveButton(positiveButton, new OnClickListener() {

        public void onClick(DialogInterface dialog, int which) {
            activity.finish();
        }
    })

}

Note that you do not need both an Activity and a Context -since the former extends the later-, unless you are expecting to pass activity as null somewhere.