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 a basic sample of how to create an Alert Dialog :

AlertDialog.Builder dialog = new AlertDialog.Builder(MainActivity.this);
dialog.setCancelable(false);
dialog.setTitle("Dialog on Android");
dialog.setMessage("Are you sure you want to delete this entry?" );
dialog.setPositiveButton("Delete", new DialogInterface.OnClickListener() {
    @Override
    public void onClick(DialogInterface dialog, int id) {
        //Action for "Delete".
    }
})
        .setNegativeButton("Cancel ", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
            //Action for "Cancel".
            }
        });

final AlertDialog alert = dialog.create();
alert.show();

Answer 2

Just be careful when you want to dismiss the dialog - use dialog.dismiss(). In my first attempt I used dismissDialog(0) (which I probably copied from some place) which sometimes works. Using the object the system supplies sounds like a safer choice.

Answer 3

public void showSimpleDialog(View view) {
    // Use the Builder class for convenient dialog construction
    AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
    builder.setCancelable(false);
    builder.setTitle("AlertDialog Title");
    builder.setMessage("Simple Dialog Message");
    builder.setPositiveButton("OK!!!", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int id) {
            //
        }
    })
    .setNegativeButton("Cancel ", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {

        }
    });

    // Create the AlertDialog object and return it
    builder.create().show();
}

Also check out my blog on Dialogs in Android, you will find all the details here: http://www.fahmapps.com/2016/09/26/dialogs-in-android-part1/.

Answer 4

Nowadays it's better to use DialogFragment instead of direct AlertDialog creation.

• How? See: https://stackoverflow.com/a/21032871/1390874
• Why? See: https://stackoverflow.com/a/13765411/1390874

Answer 5

you may try this way also, it will provide you material style dialogs

private void showDialog()
{
    String text2 = "<font color=#212121>Medi Notification</font>";//for custom title color

    AlertDialog.Builder builder = new AlertDialog.Builder(this, R.style.AppCompatAlertDialogStyle);
    builder.setTitle(Html.fromHtml(text2));

    String text3 = "<font color=#A4A4A4>You can complete your profile now or start using the app and come back later</font>";//for custom message
    builder.setMessage(Html.fromHtml(text3));

    builder.setPositiveButton("DELETE", new DialogInterface.OnClickListener()
    {
        @Override
        public void onClick(DialogInterface dialog, int which)
        {
            toast = Toast.makeText(getApplicationContext(), "DELETE", Toast.LENGTH_SHORT);
            toast.setGravity(Gravity.CENTER, 0, 0);
            toast.show();              
        }
    });

    builder.setNegativeButton("CANCEL", new DialogInterface.OnClickListener()
    {
        @Override
        public void onClick(DialogInterface dialog, int which)
        {
            toast = Toast.makeText(getApplicationContext(), "CANCEL", Toast.LENGTH_SHORT);
            toast.setGravity(Gravity.CENTER, 0, 0);
            toast.show();
        }
    });
    builder.show();
}

Answer 6

import android.app.*;
import android.os.Bundle;
import android.view.Gravity;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup.LayoutParams;
import android.widget.*;

public class ShowPopUp extends Activity {

PopupWindow popUp;
LinearLayout layout;
TextView tv;
LayoutParams params;
LinearLayout mainLayout;
Button but;
boolean click = true;


public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    popUp = new PopupWindow(this);
    layout = new LinearLayout(this);
    mainLayout = new LinearLayout(this);
    tv = new TextView(this);
    but = new Button(this);
    but.setText("Click Me");
    but.setOnClickListener(new OnClickListener() {

        public void onClick(View v) {
            if (click) {
                popUp.showAtLocation(mainLayout, Gravity.BOTTOM, 10, 10);
                popUp.update(50, 50, 300, 80);
                click = false;
            } else {
                popUp.dismiss();
                click = true;
            }
        }

    });
    params = new LayoutParams(LayoutParams.WRAP_CONTENT,
            LayoutParams.WRAP_CONTENT);
    layout.setOrientation(LinearLayout.VERTICAL);
    tv.setText("Hi this is a sample text for popup window");
    layout.addView(tv, params);
    popUp.setContentView(layout);
    // popUp.showAtLocation(layout, Gravity.BOTTOM, 10, 10);
    mainLayout.addView(but, params);
    setContentView(mainLayout);
       }
   }