// Copyright (c) 2014 AlphaSierraPapa for the SharpDevelop Team // // Permission is hereby granted, free of charge, to any person obtaining a copy of this // software and associated documentation files (the "Software"), to deal in the Software // without restriction, including without limitation the rights to use, copy, modify, merge, // publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons // to whom the Software is furnished to do so, subject to the following conditions: // // The above copyright notice and this permission notice shall be included in all copies or // substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, // INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR // PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE // FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER // DEALINGS IN THE SOFTWARE. using ICSharpCode.AvalonEdit.Utils; using System; using System.Collections.Generic; using System.Collections.ObjectModel; using System.Windows.Input; namespace ICSharpCode.AvalonEdit.Editing { /// <summary> /// A set of input bindings and event handlers for the text area. /// </summary> /// <remarks> /// <para> /// There is one active input handler per text area (<see cref="Editing.TextArea.ActiveInputHandler"/>), plus /// a number of active stacked input handlers. /// </para> /// <para> /// The text area also stores a reference to a default input handler, but that is not necessarily active. /// </para> /// <para> /// Stacked input handlers work in addition to the set of currently active handlers (without detaching them). /// They are detached in the reverse order of being attached. /// </para> /// </remarks> public interface ITextAreaInputHandler { /// <summary> /// Gets the text area that the input handler belongs to. /// </summary> TextArea TextArea { get; } /// <summary> /// Attaches an input handler to the text area. /// </summary> void Attach(); /// <summary> /// Detaches the input handler from the text area. /// </summary> void Detach(); } /// <summary> /// Stacked input handler. /// Uses OnEvent-methods instead of registering event handlers to ensure that the events are handled in the correct order. /// </summary> public abstract class TextAreaStackedInputHandler : ITextAreaInputHandler { readonly TextArea textArea; /// <inheritdoc/> public TextArea TextArea { get { return textArea; } } /// <summary> /// Creates a new TextAreaInputHandler. /// </summary> protected TextAreaStackedInputHandler(TextArea textArea) { if (textArea == null) throw new ArgumentNullException("textArea"); this.textArea = textArea; } /// <inheritdoc/> public virtual void Attach() { } /// <inheritdoc/> public virtual void Detach() { } /// <summary> /// Called for the PreviewKeyDown event. /// </summary> public virtual void OnPreviewKeyDown(KeyEventArgs e) { } /// <summary> /// Called for the PreviewKeyUp event. /// </summary> public virtual void OnPreviewKeyUp(KeyEventArgs e) { } } /// <summary> /// Default-implementation of <see cref="ITextAreaInputHandler"/>. /// </summary> /// <remarks><inheritdoc cref="ITextAreaInputHandler"/></remarks> public class TextAreaInputHandler : ITextAreaInputHandler { readonly ObserveAddRemoveCollection<CommandBinding> commandBindings; readonly ObserveAddRemoveCollection<InputBinding> inputBindings; readonly ObserveAddRemoveCollection<ITextAreaInputHandler> nestedInputHandlers; readonly TextArea textArea; bool isAttached; /// <summary> /// Creates a new TextAreaInputHandler. /// </summary> public TextAreaInputHandler(TextArea textArea) { if (textArea == null) throw new ArgumentNullException("textArea"); this.textArea = textArea; commandBindings = new ObserveAddRemoveCollection<CommandBinding>(CommandBinding_Added, CommandBinding_Removed); inputBindings = new ObserveAddRemoveCollection<InputBinding>(InputBinding_Added, InputBinding_Removed); nestedInputHandlers = new ObserveAddRemoveCollection<ITextAreaInputHandler>(NestedInputHandler_Added, NestedInputHandler_Removed); } /// <inheritdoc/> public TextArea TextArea { get { return textArea; } } /// <summary> /// Gets whether the input handler is currently attached to the text area. /// </summary> public bool IsAttached { get { return isAttached; } } #region CommandBindings / InputBindings /// <summary> /// Gets the command bindings of this input handler. /// </summary> public ICollection<CommandBinding> CommandBindings { get { return commandBindings; } } void CommandBinding_Added(CommandBinding commandBinding) { if (isAttached) textArea.CommandBindings.Add(commandBinding); } void CommandBinding_Removed(CommandBinding commandBinding) { if (isAttached) textArea.CommandBindings.Remove(commandBinding); } /// <summary> /// Gets the input bindings of this input handler. /// </summary> public ICollection<InputBinding> InputBindings { get { return inputBindings; } } void InputBinding_Added(InputBinding inputBinding) { if (isAttached) textArea.InputBindings.Add(inputBinding); } void InputBinding_Removed(InputBinding inputBinding) { if (isAttached) textArea.InputBindings.Remove(inputBinding); } /// <summary> /// Adds a command and input binding. /// </summary> /// <param name="command">The command ID.</param> /// <param name="modifiers">The modifiers of the keyboard shortcut.</param> /// <param name="key">The key of the keyboard shortcut.</param> /// <param name="handler">The event handler to run when the command is executed.</param> public void AddBinding(ICommand command, ModifierKeys modifiers, Key key, ExecutedRoutedEventHandler handler) { this.CommandBindings.Add(new CommandBinding(command, handler)); this.InputBindings.Add(new KeyBinding(command, key, modifiers)); } #endregion #region NestedInputHandlers /// <summary> /// Gets the collection of nested input handlers. NestedInputHandlers are activated and deactivated /// together with this input handler. /// </summary> public ICollection<ITextAreaInputHandler> NestedInputHandlers { get { return nestedInputHandlers; } } void NestedInputHandler_Added(ITextAreaInputHandler handler) { if (handler == null) throw new ArgumentNullException("handler"); if (handler.TextArea != textArea) throw new ArgumentException("The nested handler must be working for the same text area!"); if (isAttached) handler.Attach(); } void NestedInputHandler_Removed(ITextAreaInputHandler handler) { if (isAttached) handler.Detach(); } #endregion #region Attach/Detach /// <inheritdoc/> public virtual void Attach() { if (isAttached) throw new InvalidOperationException("Input handler is already attached"); isAttached = true; textArea.CommandBindings.AddRange(commandBindings); textArea.InputBindings.AddRange(inputBindings); foreach (ITextAreaInputHandler handler in nestedInputHandlers) handler.Attach(); } /// <inheritdoc/> public virtual void Detach() { if (!isAttached) throw new InvalidOperationException("Input handler is not attached"); isAttached = false; foreach (CommandBinding b in commandBindings) textArea.CommandBindings.Remove(b); foreach (InputBinding b in inputBindings) textArea.InputBindings.Remove(b); foreach (ITextAreaInputHandler handler in nestedInputHandlers) handler.Detach(); } #endregion } }