Question

我有一个按钮并设置了它的背景图像。如何在触摸时更改其运行时的图像，并在触摸消除后再次更改为上一图像。我尝试了以下代码，但是dint得到了所需的结果 -

private void button1_click(object sender, RoutedEventArgs e)
{
    Button source = (Button)sender;
    Image content = source.Content as Image;
    if (null != content)
    {
        content.Source = new BitmapImage(new Uri("image path"));
    }
}

提前致谢。

Answer 1

您必须修改按钮的模板。如果你有Expression Blend，你可以右键单击你的按钮并选择编辑模板 - ＆gt;编辑副本...然后选择Blend中的States窗格（通常在左侧）和那里的Pressed状态。在对象和时间轴中选择ButtonBackground并在“属性”窗格中设置所需的背景（通常在右侧）。

如果您没有Blend，您应该只为按钮创建一个新模板，并修改PAM状态的XAML。

默认按钮模板如下所示：

<ControlTemplate TargetType="Button">
    <Grid Background="Transparent">
        <VisualStateManager.VisualStateGroups>
            <VisualStateGroup x:Name="CommonStates">
                <VisualState x:Name="Normal"/>
                <VisualState x:Name="MouseOver"/>
                <VisualState x:Name="Pressed">
                    <Storyboard>
                        <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Foreground" Storyboard.TargetName="ContentContainer">
                            <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PhoneBackgroundBrush}"/>
                        </ObjectAnimationUsingKeyFrames>
                        <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Background" Storyboard.TargetName="ButtonBackground">
                            <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PhoneForegroundBrush}"/>
                        </ObjectAnimationUsingKeyFrames>
                        <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="BorderBrush" Storyboard.TargetName="ButtonBackground">
                            <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PhoneForegroundBrush}"/>
                        </ObjectAnimationUsingKeyFrames>
                    </Storyboard>
                </VisualState>
                <VisualState x:Name="Disabled">
                    <Storyboard>
                        <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Foreground" Storyboard.TargetName="ContentContainer">
                            <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PhoneDisabledBrush}"/>
                        </ObjectAnimationUsingKeyFrames>
                        <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="BorderBrush" Storyboard.TargetName="ButtonBackground">
                            <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PhoneDisabledBrush}"/>
                        </ObjectAnimationUsingKeyFrames>
                        <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Background" Storyboard.TargetName="ButtonBackground">
                            <DiscreteObjectKeyFrame KeyTime="0" Value="Transparent"/>
                        </ObjectAnimationUsingKeyFrames>
                    </Storyboard>
                </VisualState>
            </VisualStateGroup>
        </VisualStateManager.VisualStateGroups>
        <Border x:Name="ButtonBackground" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" CornerRadius="0" Margin="{StaticResource PhoneTouchTargetOverhang}">
            <ContentControl x:Name="ContentContainer" ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" Foreground="{TemplateBinding Foreground}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"/>
        </Border>
    </Grid>
</ControlTemplate>

请注意，标准动画将背景设置为处于“按下状态”的PhoneForegroundBrush

<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Background" Storyboard.TargetName="ButtonBackground">
    <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PhoneForegroundBrush}"/>
</ObjectAnimationUsingKeyFrames>

您所要做的就是定义您的图片画笔资源，并在此处用您的画笔键替换PhoneForegroundBrush。

单击时如何更改按钮的背景图像？

1 个答案: