Android: Passing parameters to Alert Dialog

Question

I am showing a simple Alert Dialog with OK/Cancel buttons. When user clicks OK, some code runs - that needs a parameter.

AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(
        MainActivity.this);
        alertDialogBuilder
        .setTitle("Are you sure?")
        .setCancelable(false)
        .setPositiveButton("OK", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int id) {
                //TODO: Do something with parameter.
            }
        })
        .setNegativeButton("Cancel",
                new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int id) {
                        dialog.cancel();

                    }
                });

// create alert dialog
AlertDialog alertDialog = alertDialogBuilder.create();

// show it
alertDialog.show();

How do i pass the parameter to AlertDialog?

Answer 1

If you declare the variable as final then you can set it in your code before calling AlertDialog.Builder() and then access it in the onClick(), like this:

    final int someParameter = someValue;

    AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(
            this);
            alertDialogBuilder
            .setTitle("Are you sure?")
            .setCancelable(false)
            .setPositiveButton("OK", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int id) {
                    // Do something with parameter.
                    doSomeStuff(someParameter);
                }
            })
            .setNegativeButton("Cancel",
                    new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int id) {
                            dialog.cancel();

                        }
                    });

    // create alert dialog
    AlertDialog alertDialog = alertDialogBuilder.create();

    // show it
    alertDialog.show();

This way, someParameter is implicitly passed to onClick() via a function closure, so there is no need to subclass AlertDialog or add extra member variables to your Activity.