xwt/Xwt.WPF/Xwt.WPFBackend/CustomWidgetBackend.cs

83 строки
2.4 KiB
C#

//
// CustomWidgetBackend.cs
//
// Author:
// Eric Maupin <ermau@xamarin.com>
//
// Copyright (c) 2012 Xamarin, Inc.
//
// 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 System.Windows.Controls;
using Xwt.Backends;
using SW = System.Windows;
namespace Xwt.WPFBackend
{
public class CustomWidgetBackend
: WidgetBackend, ICustomWidgetBackend
{
Widget child;
public CustomWidgetBackend()
{
Widget = new ExUserControl ();
}
public void SetContent (IWidgetBackend widget)
{
if (widget != null) {
child = (Widget)((WidgetBackend)widget).Frontend;
UserControl.Content = widget.NativeWidget;
}
else {
child = null;
UserControl.Content = null;
}
}
protected UserControl UserControl
{
get { return (UserControl) Widget; }
}
// The size of the container is the size of the child,
// so we redirect size calculations to the child.
public override Size GetPreferredSize (SizeConstraint widthConstraint, SizeConstraint heightConstraint)
{
return child != null ? child.Surface.GetPreferredSize (widthConstraint, heightConstraint) : Size.Zero;
}
}
class ExUserControl : UserControl, IWpfWidget
{
public WidgetBackend Backend
{
get;
set;
}
protected override SW.Size MeasureOverride (SW.Size constraint)
{
var s = base.MeasureOverride (constraint);
return Backend.MeasureOverride (constraint, s);
}
}
}