Question

package com.example.test3;

import java.util.HashMap;

import android.os.Bundle;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.DialogFragment;
import android.app.FragmentManager;
import android.content.Context;
import android.content.DialogInterface;
import android.content.SharedPreferences;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;

public class Test3 extends Activity {

    Button testShowPinDialogButton;
    public AlertDialog alertCreate;
    AlertDialog.Builder alert;
    private HashMap<String, Boolean> pinDialogState;
    EditText input;
    Context context;
    private String tag = "Test3";
    private String click1 = "click1";
    private SharedPreferences sharedPreferences;
    private SharedPreferences.Editor editor;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_test3);
        context = this;
        sharedPreferences = context.getSharedPreferences(click1, MODE_PRIVATE);
        editor = sharedPreferences.edit();
        testShowPinDialogButton = (Button) findViewById(R.id.testShowPinDialogBbutton);
        testShowPinDialogButton.setOnClickListener(showPinDialog);
        pinDialogState = new HashMap<String, Boolean>();
        Log.d(tag, "onCreate()");
    }

    private OnClickListener showPinDialog = new OnClickListener() {

        @Override
        public void onClick(View v) {
            launchDialog();
        }
    };

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.activity_test3, menu);
        return true;
    }

    protected void launchDialog() {
        alert = new AlertDialog.Builder(context);
        alert.setTitle("Title");
        alert.setMessage("Message");

        alert.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int whichButton) {

            }
        });

        alert.setNegativeButton("Cancel",
                new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int whichButton) {
                        dialog.dismiss();
                    }
                });

        Log.d(tag, "launchDialog()");
        alertCreate = alert.create();
        alertCreate.show();
    }

    @Override
    protected void onPause() {
        super.onPause();
        Log.d(tag, "onPause()");
        if (alertCreate != null) {
//          alertCreate.dismiss();
            editor.putBoolean(click1, true);
            editor.commit();
        }
    }

    @Override
    protected void onRestart() {
        super.onRestart();

    }

    @Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onResume();
        Log.d("Test3", "onResume()");
        boolean isShown = sharedPreferences.getBoolean(click1, false);
        if (isShown) {
//          alertCreate.show();
//          launchDialog();
        }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        Log.d("Test3", "onDestroy()");
    }

}

The alert dialog stays there if I home out on it. So, if I click the show dialog button and then home out and come back to the app, the dialog is still there. But if I turn on the “Don’t keep activities” option under developer options then the alert dialog is not there. Is it possible to keep it there?

Answer 1

The easiest way (but deprecated now) to do this is to use showDialog(int) and override the onCreateDialog(int) method and provide your custom implementation. This will show your dialog (duh) and re-display it if your activity is recreated (e.g. orientation switch).

Original (non fragment) dialog tutorial

Once you get this working you might want to try to use DialogFragment instead, which is the way to do this going forward.

Documentation on modern Fragment Dialogs