Navigation:  I Want To... > Basics > Change the icon of a toolbar button when pressed

Use Case

Relevant Architecture

Relevant Types

Sample Code

using System;

using ClearCanvas.Common;

using ClearCanvas.Common.Utilities;

using ClearCanvas.Desktop;

using ClearCanvas.Desktop.Actions;

using ClearCanvas.ImageViewer;

using ClearCanvas.ImageViewer.BaseTools;

 

// ... (other using namespace statements here)

 

namespace MyPlugin.Basics

{

   [MenuAction("stateToggle", "global-menus/MenuTools/MenuStandard/MenuIconToggleTool", "Toggle")]

   [ButtonAction("stateToggle", "global-toolbars/ToolbarStandard/ToolbarIconToggleTool", "Toggle")]

   [Tooltip("stateToggle", "TooltipIconToggleTool")]

   [IconSetObserver("stateToggle", "StateIconSet", "StateChanged")]

   [EnabledStateObserver("stateToggle", "Enabled", "EnabledChanged")]

   //

   // ... (other action attributes here)

   [ExtensionOf(typeof (ImageViewerToolExtensionPoint))]

   public class IconToggleTool : ImageViewerTool

   {

      private readonly IconSet _trueIcons;

      private readonly IconSet _falseIcons;

      private bool _state;

      private event EventHandler _stateChangedEvent;

 

      public IconToggleTool()

      {

         _trueIcons = new IconSet(IconScheme.Colour, "Icons.TrueSmall.png", "Icons.TrueMedium.png", "Icons.TrueLarge.png");

         _falseIcons = new IconSet(IconScheme.Colour, "Icons.FalseSmall.png", "Icons.FalseMedium.png", "Icons.FalseLarge.png");

      }

 

      public IconSet StateIconSet

      {

         get { return this.State ? _trueIcons : _falseIcons; }

      }

 

      public bool State

      {

         get { return _state; }

         set

         {

            if (_state != value)

            {

               _state = value;

               EventsHelper.Fire(_stateChangedEvent, this, EventArgs.Empty);

            }

         }

      }

 

      public event EventHandler StateChanged

      {

         add { _stateChangedEvent += value; }

         remove { _stateChangedEvent -= value; }

      }

 

      public void Toggle()

      {

         this.State = !this.State;

      }

   }

}

Remarks

In the example above, the IconSetObserverAttribute listens for the StateChanged event.  When that event is raised, it reads the StateIconSet property and updates the button's icon.

Examples in Code Base