7
我正在创建一个游戏桌。我想指定字段大小(一个字段是一个正方形)作为附加属性,并使用ViewPort的这个数据集值来绘制2x2矩阵(并且平铺模式将完成游戏桌面的其余部分)。TemplateBinding与转换器 - 有什么不对?
我很不知所措,因为绑定不起作用。
检测线在XAML的行为,我想有:
<DrawingBrush Viewport="0,0,100,100" ViewportUnits="Absolute" TileMode="None">
游戏桌是基于这个样本DrawingPaint的:http://msdn.microsoft.com/en-us/library/aa970904.aspx(图像是这里)
XAML:
<Window x:Class="Sokoban.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:Sokoban"
Title="Window1" Height="559" Width="419">
<Window.Resources>
<local:FieldSizeToRectConverter x:Key="fieldSizeConverter" />
<Style x:Key="GameDesk" TargetType="{x:Type Rectangle}">
<Setter Property="local:GameDeskProperties.FieldSize" Value="50" />
<Setter Property="Fill">
<Setter.Value>
<!--<DrawingBrush Viewport="0,0,100,100" ViewportUnits="Absolute" TileMode="None">-->
<DrawingBrush Viewport="{TemplateBinding local:GameDeskProperties.FieldSize, Converter={StaticResource fieldSizeConverter}}" ViewportUnits="Absolute" TileMode="None">
<DrawingBrush.Drawing>
<DrawingGroup>
<GeometryDrawing Brush="CornflowerBlue">
<GeometryDrawing.Geometry>
<RectangleGeometry Rect="0,0,100,100" />
</GeometryDrawing.Geometry>
</GeometryDrawing>
<GeometryDrawing Brush="Azure">
<GeometryDrawing.Geometry>
<GeometryGroup>
<RectangleGeometry Rect="0,0,50,50" />
<RectangleGeometry Rect="50,50,50,50" />
</GeometryGroup>
</GeometryDrawing.Geometry>
</GeometryDrawing>
</DrawingGroup>
</DrawingBrush.Drawing>
</DrawingBrush>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<StackPanel>
<Rectangle Style="{StaticResource GameDesk}" Width="300" Height="150" />
</StackPanel>
</Window>
转换器和属性定义:
using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Controls;
using System.Windows;
using System.Diagnostics;
using System.Windows.Data;
namespace Sokoban
{
public class GameDeskProperties : Panel
{
public static readonly DependencyProperty FieldSizeProperty;
static GameDeskProperties()
{
PropertyChangedCallback fieldSizeChanged =
new PropertyChangedCallback(OnFieldSizeChanged);
PropertyMetadata fieldSizeMetadata =
new PropertyMetadata(50, fieldSizeChanged);
FieldSizeProperty = DependencyProperty.RegisterAttached("FieldSize",
typeof(int), typeof(GameDeskProperties), fieldSizeMetadata);
}
public static int GetFieldSize(DependencyObject target)
{
return (int)target.GetValue(FieldSizeProperty);
}
public static void SetFieldSize(DependencyObject target, int value)
{
target.SetValue(FieldSizeProperty, value);
}
static void OnFieldSizeChanged(DependencyObject target,
DependencyPropertyChangedEventArgs e)
{
Debug.WriteLine("FieldSize just changed: " + e.NewValue);
}
}
[ValueConversion(/* sourceType */ typeof(int), /* targetType */ typeof(Rect))]
public class FieldSizeToRectConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
Debug.Assert(targetType == typeof(int));
int fieldSize = int.Parse(value.ToString());
return new Rect(0, 0, 2 * fieldSize, 2 * fieldSize);
}
public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
// should not be called in our example
throw new NotImplementedException();
}
}
}
我在Visual Studio的输出窗口中发现了这个错误: System.Windows.Data错误:2:找不到目标元素的管理FrameworkElement或FrameworkContentElement。 BindingExpression:路径=(0);的DataItem = NULL;目标元素是'DrawingBrush'(HashCode = 35191196);目标属性是'视口'(类型'Rect') – 2010-04-06 16:18:52
对不起,我没有仔细看看你设置的财产。我已经更新了答案,以便它真正起作用。 – 2010-04-06 22:30:50
谢谢,我从你以前的例子中发现了。 – 2010-04-08 18:48:04