Nuclex.Windows.Forms/Source/Messages/StandardMessageBoxManager.cs

163 lines
6.3 KiB
C#

#region CPL License
/*
Nuclex Framework
Copyright (C) 2002-2019 Nuclex Development Labs
This library is free software; you can redistribute it and/or
modify it under the terms of the IBM Common Public License as
published by the IBM Corporation; either version 1.0 of the
License, or (at your option) any later version.
This library 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
IBM Common Public License for more details.
You should have received a copy of the IBM Common Public
License along with this library
*/
#endregion
using System;
using System.Windows.Forms;
namespace Nuclex.Windows.Forms.Messages {
/// <summary>Uses task dialogs to display message boxes</summary>
public class StandardMessageBoxManager : IMessageService {
#region class MessageScope
/// <summary>Triggers the message displayed and acknowledged events</summary>
private class MessageScope : IDisposable {
/// <summary>
/// Initializes a new message scope, triggering the message displayed event
/// </summary>
/// <param name="self">Message service the scope belongs to</param>
/// <param name="image">Image of the message being displayed</param>
/// <param name="text">Text contained in the message being displayed</param>
public MessageScope(
StandardMessageBoxManager self, MessageBoxIcon image, MessageText text
) {
EventHandler<MessageEventArgs> messageDisplayed = self.MessageDisplaying;
if(messageDisplayed != null) {
messageDisplayed(this, new MessageEventArgs(image, text));
}
this.self = self;
}
/// <summary>Triggers the message acknowledged event</summary>
public void Dispose() {
EventHandler messageAcknowledged = self.MessageAcknowledged;
if(messageAcknowledged != null) {
messageAcknowledged(this, EventArgs.Empty);
}
}
/// <summary>Message service the scope belongs to</summary>
private StandardMessageBoxManager self;
}
#endregion // class MessageScope
/// <summary>Delegate for the standard message box show function</summary>
/// <param name="owner">Window that will modally display the message box</param>
/// <param name="text">Text that will be presented to the user</param>
/// <param name="caption">Contents of the message box' title bar</param>
/// <param name="buttons">Buttons available for the user to choose from</param>
/// <param name="icon">Icon that will be displayed next to the text</param>
/// <returns>The choice made by the user if multiple buttons were provided</returns>
private delegate DialogResult ShowMessageBoxDelegate(
IWin32Window owner,
string text,
string caption,
MessageBoxButtons buttons,
MessageBoxIcon icon
);
/// <summary>Triggered when a message is displayed to the user</summary>
public event EventHandler<MessageEventArgs> MessageDisplaying;
/// <summary>Triggered when the user has acknowledged the current message</summary>
public event EventHandler MessageAcknowledged;
/// <summary>Initializes a new task dialog message service</summary>
public StandardMessageBoxManager() : this(NullActiveWindowTracker.Default) { }
/// <summary>Initializes a new task dialog message service</summary>
/// <param name="tracker">
/// Active window tracker used to obtain the parent window for message boxes
/// </param>
public StandardMessageBoxManager(IActiveWindowTracker tracker) {
this.tracker = tracker;
this.showMessageDelegate = new ShowMessageBoxDelegate(MessageBox.Show);
}
/// <summary>Asks the user a question that can be answered via several buttons</summary>
/// <param name="image">Image that will be shown on the message box</param>
/// <param name="text">Text that will be shown to the user</param>
/// <param name="buttons">Buttons available for the user to click on</param>
/// <returns>The button the user has clicked on</returns>
public DialogResult ShowQuestion(
MessageBoxIcon image, MessageText text, MessageBoxButtons buttons
) {
using(var scope = new MessageScope(this, image, text)) {
return showMessageBoxInActiveUiThread(
text.Message,
text.Caption,
buttons,
image
);
}
}
/// <summary>Displays a notification to the user</summary>
/// <param name="image">Image that will be shown on the message bx</param>
/// <param name="text">Text that will be shown to the user</param>
public void ShowNotification(MessageBoxIcon image, MessageText text) {
using(var scope = new MessageScope(this, image, text)) {
showMessageBoxInActiveUiThread(
text.Message,
text.Caption,
MessageBoxButtons.OK,
image
);
}
}
/// <summary>Displays the message box in the active view's thread</summary>
/// <param name="message">Text that will be presented to the user</param>
/// <param name="caption">Contents of the message box' title bar</param>
/// <param name="buttons">Buttons available for the user to choose from</param>
/// <param name="image">Image that will be displayed next to the text</param>
/// <returns></returns>
private DialogResult showMessageBoxInActiveUiThread(
string message,
string caption,
MessageBoxButtons buttons,
MessageBoxIcon image
) {
Form mainWindow = this.tracker.ActiveWindow;
if(mainWindow != null) {
return (DialogResult)mainWindow.Invoke(
this.showMessageDelegate,
(IWin32Window)mainWindow, message, caption, buttons, image
);
}
// No window tracker or unknown main window -- just show the message box
return MessageBox.Show(message, caption, buttons, image);
}
/// <summary>Provides the currently active top-level window</summary>
private IActiveWindowTracker tracker;
/// <summary>Delegate for the MessageBox.Show() method</summary>
private ShowMessageBoxDelegate showMessageDelegate;
}
} // namespace Nuclex.Windows.Forms.Messages