How do I display an alert dialog on Android?

Question

I want to display a dialog/popup window with a message to the user that shows "Are you sure you want to delete this entry?" with one button that says 'Delete'. When Delete is touched, it should delete that entry, otherwise nothing.

I have written a click listener for those buttons, but how do I invoke a dialog or popup and its functionality?

Answer 1

This is definitely help for you. Try this code: On click of a button, you can put one, two or three buttons with an alert dialog...

SingleButtton.setOnClickListener(new View.OnClickListener() {

    public void onClick(View arg0) {
        // Creating alert Dialog with one Button

        AlertDialog alertDialog = new AlertDialog.Builder(AlertDialogActivity.this).create();

        // Setting Dialog Title
        alertDialog.setTitle("Alert Dialog");

        // Setting Dialog Message
        alertDialog.setMessage("Welcome to Android Application");

        // Setting Icon to Dialog
        alertDialog.setIcon(R.drawable.tick);

        // Setting OK Button
        alertDialog.setButton("OK", new DialogInterface.OnClickListener() {

            public void onClick(DialogInterface dialog,int which)
            {
                // Write your code here to execute after dialog    closed
                Toast.makeText(getApplicationContext(),"You clicked on OK", Toast.LENGTH_SHORT).show();
            }
        });

        // Showing Alert Message
        alertDialog.show();
    }
});

btnAlertTwoBtns.setOnClickListener(new View.OnClickListener() {

    public void onClick(View arg0) {
        // Creating alert Dialog with two Buttons

        AlertDialog.Builder alertDialog = new AlertDialog.Builder(AlertDialogActivity.this);

        // Setting Dialog Title
        alertDialog.setTitle("Confirm Delete...");

        // Setting Dialog Message
        alertDialog.setMessage("Are you sure you want delete this?");

        // Setting Icon to Dialog
        alertDialog.setIcon(R.drawable.delete);

        // Setting Positive "Yes" Button
        alertDialog.setPositiveButton("YES",
                new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog,int which) {
                        // Write your code here to execute after dialog
                        Toast.makeText(getApplicationContext(), "You clicked on YES", Toast.LENGTH_SHORT).show();
                    }
                });

        // Setting Negative "NO" Button
        alertDialog.setNegativeButton("NO",
                new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog,    int which) {
                        // Write your code here to execute after dialog
                        Toast.makeText(getApplicationContext(), "You clicked on NO", Toast.LENGTH_SHORT).show();
                        dialog.cancel();
                    }
                });

        // Showing Alert Message
        alertDialog.show();
    }
});

btnAlertThreeBtns.setOnClickListener(new View.OnClickListener() {

    public void onClick(View arg0) {
        // Creating alert Dialog with three Buttons

        AlertDialog.Builder alertDialog = new AlertDialog.Builder(
                AlertDialogActivity.this);

        // Setting Dialog Title
        alertDialog.setTitle("Save File...");

        // Setting Dialog Message
        alertDialog.setMessage("Do you want to save this file?");

        // Setting Icon to Dialog
        alertDialog.setIcon(R.drawable.save);

        // Setting Positive Yes Button
        alertDialog.setPositiveButton("YES",
            new DialogInterface.OnClickListener() {

                public void onClick(DialogInterface dialog,
                        int which) {
                    // User pressed Cancel button. Write Logic Here
                    Toast.makeText(getApplicationContext(),
                            "You clicked on YES",
                            Toast.LENGTH_SHORT).show();
                }
            });

        // Setting Negative No Button... Neutral means in between yes and cancel button
        alertDialog.setNeutralButton("NO",
            new DialogInterface.OnClickListener() {

                public void onClick(DialogInterface dialog,
                        int which) {
                    // User pressed No button. Write Logic Here
                    Toast.makeText(getApplicationContext(),
                            "You clicked on NO", Toast.LENGTH_SHORT)
                            .show();
                }
            });

        // Setting Positive "Cancel" Button
        alertDialog.setNegativeButton("Cancel",
            new DialogInterface.OnClickListener() {

                public void onClick(DialogInterface dialog,
                        int which) {
                    // User pressed Cancel button. Write Logic Here
                    Toast.makeText(getApplicationContext(),
                            "You clicked on Cancel",
                            Toast.LENGTH_SHORT).show();
                }
            });
        // Showing Alert Message
        alertDialog.show();
    }
});

Answer 2

AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setTitle("This is Title");
    builder.setMessage("This is message for Alert Dialog");
    builder.setPositiveButton("Positive Button", (dialog, which) -> onBackPressed());
    builder.setNegativeButton("Negative Button", (dialog, which) -> dialog.cancel());
    builder.show();

This is a way which alike to create the Alert dialog with some line of code.