using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Windows;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Automation;
using System.Windows.Controls;
using System.ComponentModel;
using IntegratedHelpInWPF.Languages;
namespace IntegratedHelpInWPF.AttachProperties
{
public class DynamicHelper
{
public static event EventHandler<HelperPublishEventArgs> OnHelpMessagePublished;
public static event EventHandler<HelperModeEventArgs> OnHelpModeSelection;
private static bool HelpActive { get; set; }
public static void SetDynamicHelp(UIElement element, bool value)
{
element.SetValue(DynamicHelpProperty, value);
}
public static bool GetDynamicHelp(UIElement element)
{
return (Boolean)element.GetValue(DynamicHelpProperty);
}
public static readonly DependencyProperty DynamicHelpProperty =
DependencyProperty.RegisterAttached("DynamicHelp", typeof(bool), typeof(UIElement),
new PropertyMetadata(false, DynamicHelpChanged));
private static readonly List<HelpGroup> HelpGroups = new List<HelpGroup>();
public static HelpGroup Current
{
get
{
return HelpGroups.LastOrDefault();
}
}
private static void DynamicHelpChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var element = d as UIElement;
if (null != element)
{
if (null != HelpGroups && !HelpGroups.Any(g => null != g.Element && g.Element.Equals(element)))
{
UIElement window = null;
if (element is Window)
window = (Window)element;
else
window = Window.GetWindow(element);
//Note: Use below code if you have used any custom window class other than child of Window (for example WindowBase is base of your custom window)
//if (window == null)
//{
// if (element is WindowBase)
// window = (WindowBase)element;
// else
// window = element.TryFindParent<WindowBase>();
//}
if (null != window)
{
var currentGroup = new HelpGroup { Screen = window, Element = element, ScreenAdorner = new HelpTextAdorner(element) };
var newVal = (bool)e.NewValue;
var oldVal = (bool)e.OldValue;
// Register Events
if (newVal && !oldVal)
{
if (currentGroup.Screen != null)
{
if (!currentGroup.Screen.CommandBindings.OfType<CommandBinding>().Any(c => c.Command.Equals(ApplicationCommands.Help)))
{
if (currentGroup._helpCommandBind == null)
{
currentGroup._helpCommandBind = new CommandBinding(ApplicationCommands.Help, HelpCommandExecute);
}
currentGroup.Screen.CommandBindings.Add(currentGroup._helpCommandBind);
}
if (currentGroup._helpHandler == null)
{
currentGroup._helpHandler = new MouseButtonEventHandler(ElementMouse);
}
currentGroup.Screen.PreviewMouseLeftButtonDown += currentGroup._helpHandler;
if (window is Window)
{
((Window)currentGroup.Screen).Closing += WindowClosing;
((Window)currentGroup.Screen).LocationChanged += WindowLocationChanged;
((Window)currentGroup.Screen).StateChanged += WindowStateChanged;
}
//else
// ((WindowBase)currentGroup.Screen).Closed += new EventHandler<WindowClosedEventArgs>(RadWindowClosed);
}
}
HelpGroups.Add(currentGroup);
}
}
}
}
static void WindowStateChanged(object sender, EventArgs e)
{
if (sender is Window)
{
var current = HelpGroups.Where(g => g.Screen.Equals(sender)).FirstOrDefault();
if ((sender as Window).WindowState == WindowState.Normal
|| (sender as Window).WindowState == WindowState.Maximized)
{
if (null != OnHelpModeSelection)
{
OnHelpModeSelection(Current.Element, new HelperModeEventArgs() { IsHelpActive = HelpActive, Current = Current });
}
UpdateScreen(current);
}
else
DynamicHelperViewer.ToggoleDetailMode(true);
}
}
static void WindowLocationChanged(object sender, EventArgs e)
{
var current = HelpGroups.Where(g => g.Screen.Equals(sender)).FirstOrDefault();
UpdateScreen(current, (sender is Window && (sender as Window).WindowState == WindowState.Minimized));
}
static void UpdateScreen(HelpGroup current, bool forceClose = false)
{
if (HelpActive)
{
if (current != null)
{
foreach (var item in current._popUps.Values)
{
if (null != item && null != item.Data)
{
item.Data.IsVisible = false;
item.Data.IsVisible = forceClose? false : !current.IsDetailShown;
}
}
}
}
}
static void WindowClosing(object sender, CancelEventArgs e)
{
OnClosingScreen(sender);
}
private static void OnClosingScreen(object sender)
{
var group = HelpGroups.FirstOrDefault(g => g.Screen.Equals(sender));
if (null != group)
{
HelpGroups.Remove(group);
if (null != group._helpCommandBind)
group.Screen.CommandBindings.Remove(group._helpCommandBind);
group.Screen.PreviewMouseLeftButtonDown -= group._helpHandler;
if (group.Screen is Window)
{
((Window)group.Screen).Closing -= WindowClosing;
((Window)group.Screen).LocationChanged -= WindowLocationChanged;
((Window)group.Screen).StateChanged -= WindowStateChanged;
}
//Note: Use Below Code if you have used any custom window class other than child of Window (for example WindowBase is base of your custom window)
//else
// ((WindowBase)group.Screen).Closed -= WindowBaseClosed;
group._helpHandler = null;
group._helpCommandBind = null;
group.Screen = null;
group.Element = null;
group.HelpDO = null;
group._popUps.Clear();
group._cacheText.Clear();
}
}
static void ElementMouse(object sender, System.Windows.Input.MouseButtonEventArgs e)
{
if(e.ButtonState != MouseButtonState.Pressed
|| e.ClickCount != 1)
return;
var element = sender as DependencyObject;
if (null != element)
{
UIElement window = null;
if (element is Window)
window = (Window)element;
else
window = Window.GetWindow(element);
//Note: Use bellow code if you have used any custom window class other than child of Window (for example WindowBase is base of your custom window)
//if (window == null)
//{
// if (element is WindowBase)
// window = (WindowBase) element;
// else
// window = element.TryFindParent<WindowBase>();
//}
if (null != window)
{
// Walk up the tree in case a parent element has help defined
var hitElement = (DependencyObject)window.InputHitTest(e.GetPosition(window));
var checkHelpDo = hitElement;
string helpText = Current.FetchHelpText(checkHelpDo);
while ( string.IsNullOrWhiteSpace(helpText) && checkHelpDo != null &&
!Equals(checkHelpDo, Current.Element) &&
!Equals(checkHelpDo, window))
{
checkHelpDo = (checkHelpDo is Visual)? VisualTreeHelper.GetParent(checkHelpDo) : null;
helpText = Current.FetchHelpText(checkHelpDo);
}
if (string.IsNullOrWhiteSpace(helpText))
{
Current.HelpDO = null;
}
else if (!string.IsNullOrWhiteSpace(helpText) && Current.HelpDO != checkHelpDo)
{
Current.HelpDO = checkHelpDo;
}
if (null != OnHelpMessagePublished)
OnHelpMessagePublished(checkHelpDo, new HelperPublishEventArgs() { HelpMessage = helpText, Sender = hitElement});
}
}
}
static void HelpCommandExecute(object sender, RoutedEventArgs e)
{
e.Handled = true;
ToggleHelp();
}
public static void ToggleHelp()
{
// Turn the current help off
Current.HelpDO = null;
// Toggle current state; add/remove mouse handler
HelpActive = !HelpActive;
if (null != OnHelpModeSelection)
{
OnHelpModeSelection(Current.Element, new HelperModeEventArgs() { IsHelpActive = HelpActive, Current = Current});
}
}
}
public class HelperPublishEventArgs : EventArgs
{
public string HelpMessage { get; set; }
public DependencyObject Sender { get; set; }
}
public class HelperModeEventArgs : EventArgs
{
public bool IsHelpActive { get; set; }
public HelpGroup Current { get; set; }
}
public class HelpModeViewData
{
public ControlTemplate Template { get; set; }
public DynamicHelpModel Data { get; set; }
}
public class HelpGroup
{
public bool IsDetailShown { get; set; }
public HelpTextAdorner ScreenAdorner { get; set; }
public DependencyObject HelpDO { get; set; }
public UIElement Screen { get; set; }
public UIElement Element { get; set; }
public MouseButtonEventHandler _helpHandler = null;
public CommandBinding _helpCommandBind = null;
public Dictionary<int, HelpModeViewData> _popUps = new Dictionary<int, HelpModeViewData>();
public Dictionary<int, string> _cacheText = new Dictionary<int, string>();
public string FetchHelpText(DependencyObject element)
{
if (null != element)
{
if (_cacheText.ContainsKey(element.GetHashCode()))
{
return _cacheText[element.GetHashCode()];
}
else
{
string helpText = AutomationProperties.GetHelpText(element);
if (!string.IsNullOrWhiteSpace(helpText))
{
_cacheText.Add(element.GetHashCode(), helpText);
}
return helpText;
}
}
return null;
}
}
public class HelpTextAdorner : Adorner
{
public HelpTextAdorner(UIElement adornedElement)
: base(adornedElement)
{ }
protected override int VisualChildrenCount
{
get
{
return 1;
}
}
protected override Visual GetVisualChild(int index)
{
if (index != 0) throw new ArgumentOutOfRangeException();
return _child;
}
private Control _child;
public Control Child
{
get { return _child; }
set
{
if (_child != null)
{
RemoveVisualChild(_child);
}
_child = value;
if (_child != null)
{
AddVisualChild(_child);
}
}
}
protected override Size MeasureOverride(Size constraint)
{
if(null !=Child)
{
_child.Measure(constraint);
return _child.DesiredSize;
}
return base.MeasureOverride(constraint);
}
protected override Size ArrangeOverride(Size finalSize)
{
if (null != Child)
{
_child.Arrange(new Rect(new Point(0, 0), finalSize));
return new Size(_child.ActualWidth, _child.ActualHeight);
}
return base.ArrangeOverride(finalSize);
}
//protected override void OnRender(DrawingContext drawingContext)
//{
// var segment = (this.AdornedElement as UIElement);
// if (segment != null)
// {
// var adornedElementRect = new Rect(this.AdornedElement.DesiredSize);
// //Some arbitrary drawing implements.
// var renderBrush = new SolidColorBrush(Colors.WhiteSmoke) { Opacity = 0.1 };
// drawingContext.DrawRectangle(renderBrush, null, new Rect(RenderSize));
// var ft = new FormattedText(
// LanguageLoader.GetText("HelpTextMode"), Thread.CurrentThread.CurrentCulture,
// System.Windows.FlowDirection.LeftToRight,
// new Typeface(new FontFamily("Arial"), FontStyles.Normal, FontWeights.Bold, FontStretches.Normal),
// 25, Brushes.SlateGray);
// drawingContext.DrawText(ft, new Point(adornedElementRect.TopLeft.X + 20, adornedElementRect.TopLeft.Y + 20));
// }
//}
}
}
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