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diff --git a/java/org/gnu/emacs/EmacsDialog.java b/java/org/gnu/emacs/EmacsDialog.java
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+++ b/java/org/gnu/emacs/EmacsDialog.java
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+/* Communication module for Android terminals.  -*- c-file-style: "GNU" -*-
+
+Copyright (C) 2023-2024 Free Software Foundation, Inc.
+
+This file is part of GNU Emacs.
+
+GNU Emacs is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or (at
+your option) any later version.
+
+GNU Emacs is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
+
+package org.gnu.emacs;
+
+import java.util.List;
+import java.util.ArrayList;
+
+import java.util.concurrent.Callable;
+import java.util.concurrent.FutureTask;
+
+import android.app.AlertDialog;
+
+import android.content.Context;
+import android.content.DialogInterface;
+
+import android.content.res.Resources.NotFoundException;
+import android.content.res.Resources.Theme;
+import android.content.res.TypedArray;
+
+import android.os.Build;
+
+import android.provider.Settings;
+
+import android.util.Log;
+
+import android.widget.Button;
+import android.widget.LinearLayout;
+import android.widget.FrameLayout;
+
+import android.view.ContextThemeWrapper;
+import android.view.View;
+import android.view.ViewGroup;
+import android.view.Window;
+import android.view.WindowManager;
+
+/* Toolkit dialog implementation.  This object is built from JNI and
+   describes a single alert dialog.  Then, `inflate' turns it into
+   AlertDialog.  */
+
+public final class EmacsDialog implements DialogInterface.OnDismissListener
+{
+  private static final String TAG = "EmacsDialog";
+
+  /* List of buttons in this dialog.  */
+  private List<EmacsButton> buttons;
+
+  /* Dialog title.  */
+  private String title;
+
+  /* Dialog text.  */
+  private String text;
+
+  /* Whether or not a selection has already been made.  */
+  private boolean wasButtonClicked;
+
+  /* Dialog to dismiss after click.  */
+  private AlertDialog dismissDialog;
+
+  /* The menu serial associated with this dialog box.  */
+  private int menuEventSerial;
+
+  private final class EmacsButton implements View.OnClickListener,
+				  DialogInterface.OnClickListener
+  {
+    /* Name of this button.  */
+    public String name;
+
+    /* ID of this button.  */
+    public int id;
+
+    /* Whether or not the button is enabled.  */
+    public boolean enabled;
+
+    @Override
+    public void
+    onClick (View view)
+    {
+      wasButtonClicked = true;
+      EmacsNative.sendContextMenu ((short) 0, id, menuEventSerial);
+      dismissDialog.dismiss ();
+    }
+
+    @Override
+    public void
+    onClick (DialogInterface dialog, int which)
+    {
+      wasButtonClicked = true;
+      EmacsNative.sendContextMenu ((short) 0, id, menuEventSerial);
+    }
+  };
+
+  /* Create a popup dialog with the title TITLE and the text TEXT.
+     TITLE may be NULL.  MENUEVENTSERIAL is a number which will
+     identify this popup dialog inside events it sends.  */
+
+  public static EmacsDialog
+  createDialog (String title, String text, int menuEventSerial)
+  {
+    EmacsDialog dialog;
+
+    dialog = new EmacsDialog ();
+    dialog.buttons = new ArrayList<EmacsButton> ();
+    dialog.title = title;
+    dialog.text = text;
+    dialog.menuEventSerial = menuEventSerial;
+
+    return dialog;
+  }
+
+  /* Add a button named NAME, with the identifier ID.  If DISABLE,
+     disable the button.  */
+
+  public void
+  addButton (String name, int id, boolean disable)
+  {
+    EmacsButton button;
+
+    button = new EmacsButton ();
+    button.name = name;
+    button.id = id;
+    button.enabled = !disable;
+    buttons.add (button);
+  }
+
+  /* Turn this dialog into an AlertDialog for the specified
+     CONTEXT.
+
+     Upon a button being selected, the dialog will send an
+     ANDROID_CONTEXT_MENU event with the id of that button.
+
+     Upon the dialog being dismissed, an ANDROID_CONTEXT_MENU event
+     will be sent with an id of 0.  */
+
+  public AlertDialog
+  toAlertDialog (Context context)
+  {
+    AlertDialog dialog;
+    int size, styleId, flag;
+    int[] attrs;
+    EmacsButton button;
+    EmacsDialogButtonLayout layout;
+    Button buttonView;
+    ViewGroup.LayoutParams layoutParams;
+    Theme theme;
+    TypedArray attributes;
+    Window window;
+
+    /* Wrap the context within a style wrapper.  Any dialog properties
+       tied to EmacsStyle (such as those applied by the system ``dark
+       theme'') will thus affect the dialog irrespective of whether
+       CONTEXT is an activity or the service.  */
+
+    context = new ContextThemeWrapper (context, R.style.EmacsStyle);
+
+    size = buttons.size ();
+    styleId = -1;
+
+    if (size <= 3)
+      {
+	dialog = new AlertDialog.Builder (context).create ();
+	dialog.setMessage (text);
+	dialog.setCancelable (true);
+	dialog.setOnDismissListener (this);
+
+	if (title != null)
+	  dialog.setTitle (title);
+
+	/* There are less than 4 buttons.  Add the buttons the way
+	   Android intends them to be added.  */
+
+	if (size >= 1)
+	  {
+	    button = buttons.get (0);
+	    dialog.setButton (DialogInterface.BUTTON_POSITIVE,
+			      button.name, button);
+	  }
+
+	if (size >= 2)
+	  {
+	    button = buttons.get (1);
+	    dialog.setButton (DialogInterface.BUTTON_NEGATIVE,
+			      button.name, button);
+	  }
+
+	if (size >= 3)
+	  {
+	    button = buttons.get (2);
+	    dialog.setButton (DialogInterface.BUTTON_NEUTRAL,
+			      button.name, button);
+	  }
+      }
+    else
+      {
+	/* There are more than 3 buttons.  Add them all to a special
+	   container widget that handles wrapping.  First, create the
+	   layout.  */
+
+	layout = new EmacsDialogButtonLayout (context);
+	layoutParams
+	  = new FrameLayout.LayoutParams (ViewGroup.LayoutParams.MATCH_PARENT,
+					  ViewGroup.LayoutParams.WRAP_CONTENT);
+	layout.setLayoutParams (layoutParams);
+
+	/* Add that layout to the dialog's custom view.
+
+	   android.R.id.custom is documented to work.  But looking it
+	   up returns NULL, so setView must be used instead.  */
+
+	dialog = new AlertDialog.Builder (context).setView (layout).create ();
+	dialog.setMessage (text);
+	dialog.setCancelable (true);
+	dialog.setOnDismissListener (this);
+
+	if (title != null)
+	  dialog.setTitle (title);
+
+	/* Now that the dialog has been created, set the style of each
+	   custom button to match the usual dialog buttons found on
+	   Android 5 and later.  */
+
+	if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP)
+	  {
+	    /* Obtain the Theme associated with the dialog.  */
+	    theme = dialog.getContext ().getTheme ();
+
+	    /* Resolve the dialog button style.  */
+	    attrs
+	      = new int [] { android.R.attr.buttonBarNeutralButtonStyle, };
+
+	    try
+	      {
+		attributes = theme.obtainStyledAttributes (attrs);
+
+		/* Look for the style ID.  Default to -1 if it could
+		   not be found.  */
+		styleId = attributes.getResourceId (0, -1);
+
+		/* Now clean up the TypedAttributes object.  */
+		attributes.recycle ();
+	      }
+	    catch (NotFoundException e)
+	      {
+		/* Nothing to do here.  */
+	      }
+	  }
+
+	/* Create each button and add it to the layout.  Set the style
+	   if necessary.  */
+
+	for (EmacsButton emacsButton : buttons)
+	  {
+	    if (styleId == -1)
+	      /* No specific style... */
+	      buttonView = new Button (context);
+	    else
+	      /* Use the given styleId.  */
+	      buttonView = new Button (context, null, 0, styleId);
+
+	    /* Set the text and on click handler.  */
+	    buttonView.setText (emacsButton.name);
+	    buttonView.setOnClickListener (emacsButton);
+	    buttonView.setEnabled (emacsButton.enabled);
+	    layout.addView (buttonView);
+	  }
+      }
+
+    return dialog;
+  }
+
+  /* Internal helper for display run on the main thread.  */
+
+  @SuppressWarnings("deprecation")
+  private boolean
+  display1 ()
+  {
+    Context context;
+    int size, type;
+    Button buttonView;
+    EmacsButton button;
+    AlertDialog dialog;
+    Window window;
+
+    if (EmacsActivity.focusedActivities.isEmpty ())
+      {
+	/* If focusedActivities is empty then this dialog may have
+	   been displayed immediately after another popup dialog was
+	   dismissed.  Or Emacs might legitimately be in the
+	   background, possibly displaying this popup in response to
+	   an Emacsclient request.  Try the service context if it will
+	   work, then any focused EmacsOpenActivity, and finally the
+	   last EmacsActivity to be focused.  */
+
+	if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M
+	    || Settings.canDrawOverlays (EmacsService.SERVICE))
+	  context = EmacsService.SERVICE;
+	else if (EmacsOpenActivity.currentActivity != null)
+	  context = EmacsOpenActivity.currentActivity;
+	else
+	  context = EmacsActivity.lastFocusedActivity;
+
+	if (context == null)
+	  return false;
+      }
+    else
+      /* Display using the activity context when Emacs is in the
+	 foreground, as this allows the dialog to be dismissed more
+	 consistently.  */
+      context = EmacsActivity.focusedActivities.get (0);
+
+    dialog = dismissDialog = toAlertDialog (context);
+
+    try
+      {
+	if (context == EmacsService.SERVICE)
+	  {
+	    /* Apply the system alert window type to make sure this
+	       dialog can be displayed.  */
+
+	    window = dialog.getWindow ();
+	    type = (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O
+		    ? WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY
+		    : WindowManager.LayoutParams.TYPE_PHONE);
+	    window.setType (type);
+	  }
+
+	dismissDialog.show ();
+      }
+    catch (Exception exception)
+      {
+	/* This can happen when the system decides Emacs is not in the
+	   foreground any longer.  */
+	return false;
+      }
+
+    /* If there are less than four buttons, then they must be
+       individually enabled or disabled after the dialog is
+       displayed.  */
+    size = buttons.size ();
+
+    if (size <= 3)
+      {
+	if (size >= 1)
+	  {
+	    button = buttons.get (0);
+	    buttonView
+	      = dialog.getButton (DialogInterface.BUTTON_POSITIVE);
+	    buttonView.setEnabled (button.enabled);
+	  }
+
+	if (size >= 2)
+	  {
+	    button = buttons.get (1);
+	    buttonView
+	      = dialog.getButton (DialogInterface.BUTTON_NEGATIVE);
+	    buttonView.setEnabled (button.enabled);
+	  }
+
+	if (size >= 3)
+	  {
+	    button = buttons.get (2);
+	    buttonView
+	      = dialog.getButton (DialogInterface.BUTTON_NEUTRAL);
+	    buttonView.setEnabled (button.enabled);
+	  }
+      }
+
+    return true;
+  }
+
+  /* Display this dialog for a suitable activity.
+     Value is false if the dialog could not be displayed,
+     and true otherwise.  */
+
+  public boolean
+  display ()
+  {
+    FutureTask<Boolean> task;
+
+    task = new FutureTask<Boolean> (new Callable<Boolean> () {
+	@Override
+	public Boolean
+	call ()
+	{
+	  return display1 ();
+	}
+      });
+
+    return EmacsService.<Boolean>syncRunnable (task);
+  }
+
+
+
+  @Override
+  public void
+  onDismiss (DialogInterface dialog)
+  {
+    if (wasButtonClicked)
+      return;
+
+    EmacsNative.sendContextMenu ((short) 0, 0, menuEventSerial);
+  }
+};