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using System;
using System.Collections;
using System.Windows.Threading;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Markup;
using System.Runtime.InteropServices;
using MS.Utility;
using MS.Win32;
using MS.Internal;
using MS.Internal.Data;
using MS.Internal.KnownBoxes;
namespace System.Windows.Controls.Primitives
{
/// <summary>
/// The root element inside a popup.
/// </summary>
internal sealed class PopupRoot : FrameworkElement
{
#region Constructors
static PopupRoot()
{
SnapsToDevicePixelsProperty.OverrideMetadata(typeof(PopupRoot), new FrameworkPropertyMetadata(BooleanBoxes.TrueBox));
}
/// <summary>
/// Default constructor
/// </summary>
internal PopupRoot() : base()
{
Initialize();
}
private void Initialize()
{
// Popup root has a decorator used for
// applying the transforms
_transformDecorator = new Decorator();
AddVisualChild(_transformDecorator);
// Clip so animations do not extend beyond its bounds
_transformDecorator.ClipToBounds = true;
// Under the transfrom decorator is an Adorner
// decorator that handles rendering adorners
// and the animated popup translations
_adornerDecorator = new NonLogicalAdornerDecorator();
_transformDecorator.Child = _adornerDecorator;
}
#endregion
#region Visual Children
/// <summary>
/// Returns the Visual children count.
/// </summary>
protected override int VisualChildrenCount
{
get { return 1; }
}
/// <summary>
/// Returns the child at the specified index.
/// </summary>
protected override Visual GetVisualChild(int index)
{
if (index != 0)
{
throw new ArgumentOutOfRangeException("index", index, SR.Get(SRID.Visual_ArgumentOutOfRange));
}
return _transformDecorator;
}
#endregion
#region Automation
/// <summary>
/// Creates AutomationPeer (<see cref="UIElement.OnCreateAutomationPeer"/>)
/// </summary>
protected override System.Windows.Automation.Peers.AutomationPeer OnCreateAutomationPeer()
{
return new System.Windows.Automation.Peers.PopupRootAutomationPeer(this);
}
#endregion Automation
#region Properties
internal UIElement Child
{
get
{
return _adornerDecorator.Child;
}
set
{
_adornerDecorator.Child = value;
}
}
internal Vector AnimationOffset
{
get
{
TranslateTransform transform = _adornerDecorator.RenderTransform as TranslateTransform;
if (transform != null)
{
return new Vector(transform.X, transform.Y);
}
return new Vector();
}
}
/// <summary>
/// This is the transform matrix that the popup content "inherits" from the placement target.
/// </summary>
internal Transform Transform
{
set
{
_transformDecorator.LayoutTransform = value;
}
}
#endregion
#region Layout
/// <summary>
/// Invoked when remeasuring the control is required.
/// </summary>
/// <param name="constraint">The control cannot return a size larger than the constraint.</param>
/// <returns>The size of the child restricted to 75% of screen</returns>
protected override Size MeasureOverride(Size constraint)
{
// Measure with no constraints to see how big the content wants to be.
Size desiredSize = new Size(Double.PositiveInfinity, Double.PositiveInfinity);
Popup popup = Parent as Popup;
try
{
_transformDecorator.Measure(desiredSize);
}
catch (Exception e)
{
// there have been many reports of a NullReference exception in
// Popup.OnWindowResize (633371, 764558, 780033, 835588, 899575, 915649, etc.).
// This arises when an exception aborts Measure, and the exception is caught;
// the next time layout runs, it delivers a resize request to the popup,
// which never initialized its _positionInfo.
// The catch hides the real problem (which is often the app's fault).
// By the time the null-ref happens, all the evidence is long gone.
// To help developers and users identify the real problem, store the
// exception, so that it can be reported when the crashing null-ref
// occurs.
if (popup != null)
{
popup.SavedException = e;
}
throw;
}
desiredSize = _transformDecorator.DesiredSize;
if (popup != null)
{
// If the parent is a Popup, then the desired size may need to be restricted to satisfy placement constraints.
bool restrictWidth;
bool restrictHeight;
Size restrictedSize = GetPopupSizeRestrictions(popup, desiredSize, out restrictWidth, out restrictHeight);
// If no restrictions are needed, fall through & use the original desired size.
if (restrictWidth || restrictHeight)
{
if (restrictWidth == restrictHeight)
{
// If we need to restrict in both dimensions, re-measure at the restricted size & use the result as our desiredSize.
desiredSize = Get2DRestrictedDesiredSize(restrictedSize);
}
else
{
// If we need to restrict in only one dimension, re-measure with no constraint on the other dimension.
// This will give the content a chance to wrap.
Size restricted1DDesiredSize = new Size(restrictWidth ? restrictedSize.Width : Double.PositiveInfinity,
restrictHeight ? restrictedSize.Height : Double.PositiveInfinity);
_transformDecorator.Measure(restricted1DDesiredSize);
desiredSize = _transformDecorator.DesiredSize;
// Restricting in one dimension may increase the size in the other dimension, so we need to restrict again
// to satisfy placement constraints.
restrictedSize = GetPopupSizeRestrictions(popup, desiredSize, out restrictWidth, out restrictHeight);
if (restrictWidth || restrictHeight)
{
// If a restriction is still in place, we cannot satisfy both desiredSize and placement constraints,
// so respect the placement constraints & clip the content.
desiredSize = Get2DRestrictedDesiredSize(restrictedSize);
}
}
}
}
return desiredSize;
}
/// <summary>
/// Gets teh restricted size of a popup & computes which dimensions were affected.
/// </summary>
private Size GetPopupSizeRestrictions(Popup popup, Size desiredSize, out bool restrictWidth, out bool restrictHeight)
{
Size restrictedSize = popup.RestrictSize(desiredSize);
restrictWidth = Math.Abs(restrictedSize.Width - desiredSize.Width) > Popup.Tolerance;
restrictHeight = Math.Abs(restrictedSize.Height - desiredSize.Height) > Popup.Tolerance;
return restrictedSize;
}
/// <summary>
/// Measures the _transformDecorator at the restricted size to determine a new desired size.
/// </summary>
private Size Get2DRestrictedDesiredSize(Size restrictedSize)
{
_transformDecorator.Measure(restrictedSize);
Size restricted2DDesiredSize = _transformDecorator.DesiredSize;
return new Size(Math.Min(restrictedSize.Width, restricted2DDesiredSize.Width),
Math.Min(restrictedSize.Height, restricted2DDesiredSize.Height));
}
/// <summary>
/// ArrangeOverride allows for the customization of the positioning of children.
/// </summary>
/// <param name="arrangeSize">The final size that element should use to arrange itself and its children.</param>
protected override Size ArrangeOverride(Size arrangeSize)
{
_transformDecorator.Arrange(new Rect(arrangeSize));
return arrangeSize;
}
/// <summary>
/// Sets up bindings between (Min/Max)Width/Height properties on Popup and PopupRoot.
/// </summary>
/// <param name="popup">The parent Popup.</param>
internal void SetupLayoutBindings(Popup popup)
{
Binding binding = new Binding("Width");
binding.Mode = BindingMode.OneWay;
binding.Source = popup;
_adornerDecorator.SetBinding(WidthProperty, binding);
binding = new Binding("Height");
binding.Mode = BindingMode.OneWay;
binding.Source = popup;
_adornerDecorator.SetBinding(HeightProperty, binding);
binding = new Binding("MinWidth");
binding.Mode = BindingMode.OneWay;
binding.Source = popup;
_adornerDecorator.SetBinding(MinWidthProperty, binding);
binding = new Binding("MinHeight");
binding.Mode = BindingMode.OneWay;
binding.Source = popup;
_adornerDecorator.SetBinding(MinHeightProperty, binding);
binding = new Binding("MaxWidth");
binding.Mode = BindingMode.OneWay;
binding.Source = popup;
_adornerDecorator.SetBinding(MaxWidthProperty, binding);
binding = new Binding("MaxHeight");
binding.Mode = BindingMode.OneWay;
binding.Source = popup;
_adornerDecorator.SetBinding(MaxHeightProperty, binding);
}
// Popup is transparent, change opacity of root
internal void SetupFadeAnimation(Duration duration, bool visible)
{
DoubleAnimation anim = new DoubleAnimation(visible ? 0.0 : 1.0, visible ? 1.0 : 0.0, duration, FillBehavior.HoldEnd);
BeginAnimation(PopupRoot.OpacityProperty, anim);
}
// Popup is transparent, we can leave popup size alone
// and animate the translation of the popup
internal void SetupTranslateAnimations(PopupAnimation animationType, Duration duration, bool animateFromRight, bool animateFromBottom)
{
UIElement child = Child;
if (child == null)
return;
TranslateTransform transform = _adornerDecorator.RenderTransform as TranslateTransform;
if (transform == null)
{
transform = new TranslateTransform();
_adornerDecorator.RenderTransform = transform;
}
if (animationType == PopupAnimation.Scroll)
{
// If the flow direction of the child is different than ours, animate in opposite direction
FlowDirection childFlowDirection = (FlowDirection)child.GetValue(FlowDirectionProperty);
FlowDirection thisFlowDirection = FlowDirection;
if (childFlowDirection != thisFlowDirection)
{
animateFromRight = !animateFromRight;
}
double width = _adornerDecorator.RenderSize.Width;
DoubleAnimation xAnim = new DoubleAnimation(animateFromRight ? width : -width, 0.0, duration, FillBehavior.Stop);
transform.BeginAnimation(TranslateTransform.XProperty, xAnim);
}
double height = _adornerDecorator.RenderSize.Height;
DoubleAnimation yAnim = new DoubleAnimation(animateFromBottom ? height : -height, 0.0, duration, FillBehavior.Stop);
transform.BeginAnimation(TranslateTransform.YProperty, yAnim);
}
// Clear animations on this and _adorner
internal void StopAnimations()
{
BeginAnimation(PopupRoot.OpacityProperty, null);
TranslateTransform transform = _adornerDecorator.RenderTransform as TranslateTransform;
if (transform != null)
{
transform.BeginAnimation(TranslateTransform.XProperty, null);
transform.BeginAnimation(TranslateTransform.YProperty, null);
}
}
#endregion
#region Tree Overrides
internal override bool IgnoreModelParentBuildRoute(RoutedEventArgs e)
{
// We do not want QueryCursor event to bubble up past this node
if(e is QueryCursorEventArgs)
{
return true;
}
// Defer to the child to determine if we should route events up the logical tree.
FrameworkElement child = Child as FrameworkElement;
if(child != null)
{
return child.IgnoreModelParentBuildRoute(e);
}
else
{
return base.IgnoreModelParentBuildRoute(e);
}
}
#endregion
#region Data
private Decorator _transformDecorator; // The decorator used to apply animations
private AdornerDecorator _adornerDecorator;
#endregion
}
}
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