【发布时间】：2010-07-07 05:30:28
【问题描述】：
我正在开发我的第一个 WPF 应用程序，我正在测试一个自定义控件，该控件是一个必不可少的圆圈，中间有一个播放按钮。不过，我似乎遇到了一些麻烦。当我绘制我的播放按钮时，我似乎无法让它在圆圈旁边调整大小。具体来说，当我将圆调整为更宽或更高时，播放按钮多边形保持相同的大小和相同的绝对位置。有关设置我的 XAML 或代码来纠正此问题的任何指针？
现有 XAML：
<Window x:Class="WPFTest.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525" xmlns:my="clr-namespace:WPFTest">
<StackPanel>
<StackPanel.Resources>
<Style TargetType="my:GradientButton">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type my:GradientButton}">
<Grid>
<Ellipse Width="{TemplateBinding Width}" Height="{TemplateBinding Height}" Stroke="{TemplateBinding Foreground}" VerticalAlignment="Top" HorizontalAlignment="Left">
<Ellipse.Fill>
<LinearGradientBrush>
<GradientStop Color="{TemplateBinding GradientStart}" Offset="0"></GradientStop>
<GradientStop Color="{TemplateBinding GradientEnd}" Offset="1"></GradientStop>
</LinearGradientBrush>
</Ellipse.Fill>
</Ellipse>
<Polygon Points="{TemplateBinding PlayPoints}" Fill="{TemplateBinding Foreground}" />
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</StackPanel.Resources>
<my:GradientButton Content="Button" Height="50" x:Name="gradientButton1" Width="50" GradientStart="#FFCCCCCC" GradientEnd="#FFAAAAAA" PlayPoints="18,12 35,25 18,38" />
</StackPanel>
</Window>
代码：
public class GradientButton : Button
{
internal static DependencyProperty GradientStartProperty;
internal static DependencyProperty GradientEndProperty;
internal static DependencyProperty PlayPointsProperty;
static GradientButton()
{
GradientStartProperty = DependencyProperty.Register("GradientStart", typeof(Color), typeof(GradientButton));
GradientEndProperty = DependencyProperty.Register("GradientEnd", typeof(Color), typeof(GradientButton));
PlayPointsProperty = DependencyProperty.Register("PlayPoints", typeof(PointCollection), typeof(GradientButton));
}
public Color GradientStart
{
get { return (Color)base.GetValue(GradientStartProperty); }
set { SetValue(GradientStartProperty, value); }
}
public Color GradientEnd
{
get { return (Color)base.GetValue(GradientEndProperty); }
set { SetValue(GradientEndProperty, value); }
}
public PointCollection PlayPoints
{
get
{
//this is where I'm trying to make the resizing dynamic, but this property never seems to get hit when I put in a breakpoint?
PointCollection result = new PointCollection();
double top = this.Width / 2.778;
double left = this.Width / 4.167;
double middle = this.Height / 2.00;
double right = this.Width / 1.429;
double bottom = this.Height / 1.316;
result.Add(new Point(left, top));
result.Add(new Point(right, middle));
result.Add(new Point(left, bottom));
return result;
}
set { SetValue(PlayPointsProperty, value); }
}
}
【问题讨论】：
-
如果你想要的只是一个显示一些精美图形的按钮，比如一个充满彩虹色的圆圈中的箭头，你不需要创建自己的按钮类。仅当您添加一些新行为时才执行此操作，例如三次单击。您最好为此创建一个样式并使用常规按钮控件。