//  AlertDialogDemoActivity.java  (c) Kari Laitinen

//  http://www.naturalprogramming.com

//  2013-04-02  File created.
//  2015-03-17  Latest modification.

//  A long press on the touch display shows an alert dialog.

//  This program also shows how an activity can terminate itself.

//  When creating a project for this app, set the Minimum Required SDK
//  to something like Android 4.0. This program will not work on old
//  Androids.

//  This program is a simplified version of the program shown at:
//    http://developer.android.com/reference/android/app/DialogFragment.html

//  To run this program, create a project and set AlertDialogDemoActivity as
//  its main activity, and use the package name that is used here.
//  The you can use this file to overwrite the .java file created by 
//  Android Studio.

package alert.dialog.demo ;

import android.app.Activity ;
import android.os.Bundle ;
import android.graphics.* ;  // Classes Canvas, Color, Paint, RectF, etc.
import android.view.View ;
import android.view.MotionEvent ;
import android.view.GestureDetector ;
import android.content.Context ;
import java.util.ArrayList ;

import android.app.AlertDialog ;
import android.app.Dialog ;
import android.content.DialogInterface ;
import android.app.DialogFragment ;


class AlertDialogDemoView extends View
                          implements GestureDetector.OnGestureListener
{
   GestureDetector gesture_detector ;

   public AlertDialogDemoView( Context context ) 
   {
      super( context ) ;

      gesture_detector = new GestureDetector( context, this ) ;
   }


   public boolean onDown( MotionEvent motion_event )
   {
      return true ;
   }

   public boolean onFling( MotionEvent first_down_motion,
                           MotionEvent last_move_motion,
                           float velocity_x, float velocity_y )
   {
      return true ;
   }

   public void onLongPress( MotionEvent first_down_motion )
   {
      ((AlertDialogDemoActivity) getContext()).show_alert_dialog() ;
   }

   public boolean onScroll( MotionEvent first_down_motion,
                            MotionEvent last_move_motion,
                            float distance_x, float distance_y )
   {
      return true ;
   }

   public void onShowPress( MotionEvent down_motion )
   {
   }

   public boolean onSingleTapUp( MotionEvent up_motion )
   {
      return true ;
   }

   public boolean onTouchEvent ( MotionEvent motion_event )
   {
      gesture_detector.onTouchEvent( motion_event ) ;

      return true ;
   }


   protected void onDraw( Canvas canvas ) 
   {
      Paint outline_paint = new Paint() ;
      outline_paint.setStyle( Paint.Style.STROKE ) ;
      outline_paint.setTextSize( 24 ) ;
      // Default color for a Paint is black.

      canvas.drawText( "LONG PRESS SHOWS AN ALERT DIALOG",
                       20, 80, outline_paint ) ;
   }
}


public class AlertDialogDemoActivity extends Activity
{
   public static class AlertDialogFragment extends DialogFragment
   {
      public static AlertDialogFragment newInstance( String given_title )
      {
         AlertDialogFragment alert_dialog_fragment = new AlertDialogFragment() ;
         Bundle arguments = new Bundle() ;
         arguments.putString( "title", given_title ) ;
         alert_dialog_fragment.setArguments( arguments ) ;
         return alert_dialog_fragment ;
      }

      @Override
      public Dialog onCreateDialog( Bundle savedInstanceState )
      {
         String dialog_title = getArguments().getString( "title" ) ;

         return new AlertDialog.Builder( getActivity() )
            //.setIcon(R.drawable.alert_dialog_icon)
            .setTitle( dialog_title )
            .setPositiveButton( "Yes",
               new DialogInterface.OnClickListener()
               {
                  public void onClick(DialogInterface dialog, int whichButton )
                  {
                     ((AlertDialogDemoActivity)getActivity()).do_positive_things() ;
                  }
               } )
            .setNegativeButton( "No",
               new DialogInterface.OnClickListener()
               {
                  public void onClick(DialogInterface dialog, int whichButton )
                  {
                     ((AlertDialogDemoActivity)getActivity()).do_negative_things() ;
                  }
               } )
            .create() ;
      }
   }

   public void onCreate( Bundle savedInstanceState )
   {
      super.onCreate( savedInstanceState ) ;

      setContentView( new AlertDialogDemoView( this ) ) ;
   }


   //  The following method will be called from the View-based class.

   public void show_alert_dialog() 
   {
       DialogFragment alert_dialog_fragment = AlertDialogFragment.newInstance(
                                                    "EXIT THIS ACTIVITY ?" ) ;

       alert_dialog_fragment.show( getFragmentManager(), "dialog" ) ;
   }


   public void do_positive_things()
   {
      finish() ; // This will finish the entire activity.
   }

   public void do_negative_things()
   {
   }
}