c# - 语法问题 : Can't Change BackGround Of Particular button?

Question

1. 我有一个 ==> UserControl。

2. 在那个 UserControl 里面 ==> 一个 ItemsControl。

   现在 ItemsControl 生成 Button 的 根据 ItemsSource 给它。我为这些按钮提供了一些样式。

   ==>按钮在 Pages.xaml 中。

   ==>和 DataPagerResourceDictionary.xaml 中的样式。

我在 Mainwindow.xaml 中使用了 UserControl。但我无法根据按钮内容更改特定按钮的背景。

您可以从 here 下载完整代码.

如果我不为按钮提供样式，下面的代码可以正常工作。

for (int i = 0; i < displayPages.pageControl.Items.Count; i++)
        {
            var container = displayPages.pageControl.ItemContainerGenerator.ContainerFromIndex(i) as ContentPresenter;
            var button = container.ContentTemplate.FindName("pageNumberButton", container) as Button;
            if (button.Content == "  3  ")
            {
                button.Background = Brushes.Red;
            }
        } 

我已经提供了样式到下面的代码片段中的按钮[看看独立的 Pages.xaml]。

<ItemsControl.ItemTemplate>
                <DataTemplate>
                    <Button x:Name="pageNumberButton"  Style="{StaticResource TransparentButton}"   Content="{Binding Path=Page_Number}"></Button>
                </DataTemplate>
            </ItemsControl.ItemTemplate>

或者看看下面的代码:

MainWindow.xaml

<Window x:Class="StylingProblem.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:Local="clr-namespace:StylingProblem">
    <Grid>
        <Local:Pages x:Name="displayPages"></Local:Pages>
        <Button Content="Change Color Button" Height="23" HorizontalAlignment="Left" Margin="149,164,0,0" Name="button1" VerticalAlignment="Top" Width="133" Click="button1_Click" />
    </Grid>
</Window>

MainWindow.xaml.cs

public partial class MainWindow : Window
    {
        ObservableCollection<PageNumber> pageCollection = new ObservableCollection<PageNumber>();

        public MainWindow()
        {
            InitializeComponent();
            pageCollection.Add(new PageNumber("  1  "));
            pageCollection.Add(new PageNumber("  2  "));
            pageCollection.Add(new PageNumber("  3  "));
            pageCollection.Add(new PageNumber("  4  "));
            pageCollection.Add(new PageNumber("  5  "));
            pageCollection.Add(new PageNumber("  6  "));

            this.DataContext = this;
        }

        public ObservableCollection<PageNumber> PageCollection
        {
            get
            {
                return this.pageCollection;
            }
            set
            {
                this.pageCollection = value;
            }
        }

        private void button1_Click(object sender, RoutedEventArgs e)
        {
            //Chage Color of Perticular button here
            //Suppose say change the color of button with content == "  3  "

            #region --  THIS CODE WORKS FINE IF I DON'T PROVIDE ANY STYLE TO BUTTON [see Pages.xaml]  --
            for (int i = 0; i < displayPages.pageControl.Items.Count; i++)
            {
                var container = displayPages.pageControl.ItemContainerGenerator.ContainerFromIndex(i) as ContentPresenter;
                var button = container.ContentTemplate.FindName("pageNumberButton", container) as Button;
                if (button.Content == "  3  ")
                {
                    button.Background = Brushes.Red;
                }
            } 
            #endregion


        }

Pages.xaml [用户控制]

<UserControl x:Class="StylingProblem.Pages"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             mc:Ignorable="d" 
              >
    <UserControl.Resources>
        <ResourceDictionary Source="DataPagerResourceDictionary.xaml"/>
    </UserControl.Resources>
    <Grid>
        <ItemsControl Name="pageControl" ItemsSource="{Binding Path=PageCollection}">
            <ItemsControl.Template>
                <ControlTemplate TargetType="ItemsControl">
                    <Border >
                        <StackPanel>
                            <ItemsPresenter></ItemsPresenter>
                        </StackPanel>
                    </Border>
                </ControlTemplate>
            </ItemsControl.Template>
            <ItemsControl.ItemsPanel x:Uid="pageItemTemplate">
                <ItemsPanelTemplate>
                    <StackPanel Orientation="Horizontal"/>
                </ItemsPanelTemplate>
            </ItemsControl.ItemsPanel>
            <ItemsControl.ItemTemplate>
                <DataTemplate>
                    <Button x:Name="pageNumberButton" Style="{StaticResource TransparentButton}"  Content="{Binding Path=Page_Number}"></Button>
                </DataTemplate>
            </ItemsControl.ItemTemplate>

        </ItemsControl>
    </Grid>
</UserControl>

按钮样式:DataPagerResourceDictionary.xaml

<ResourceDictionary
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
   >
    <Style TargetType="Button" x:Key="TransparentButton">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="Button">
                    <Border  CornerRadius="2,2,2,2"  HorizontalAlignment="Center" x:Name="borderTemplate" Background="Transparent">
                        <ContentPresenter/>
                    </Border>
                    <ControlTemplate.Triggers>
                        <Trigger Property="IsMouseOver" Value="true">
                            <Setter TargetName="borderTemplate"  Property="Border.BorderBrush" Value="Gray" />
                            <Setter TargetName="borderTemplate"  Property="Border.BorderThickness" Value="1" />
                        </Trigger>
                        <Trigger Property="IsPressed" Value="true">
                            <Setter TargetName="borderTemplate"  Property="Border.BorderBrush" Value="Lime" />
                        </Trigger>
                        <Trigger Property="IsFocused" Value="true">
                            <Setter TargetName="borderTemplate"  Property="Border.Background" Value="#FD7" />
                        </Trigger>
                        <Trigger Property="IsEnabled" Value="false">
                            <Setter TargetName="borderTemplate"  Property="Border.Background" Value="LightGray"></Setter>
                        </Trigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</ResourceDictionary>

谢谢......................................

Answer 1

您在样式中覆盖了按钮的模板，因此永远不会使用背景颜色

默认按钮模板如下所示:

<Button Background="SomeColor">
    <Button.Content>
</Button>

你正在覆盖模板说

<Border>
    <Button.Content>
</Border>

您需要将 Border 的背景色绑定(bind)到 {TemplateBinding Background}，以便它使用 Button 的背景色。

我还建议使用 DataTrigger 而不是代码隐藏来更改按钮的背景颜色。

<Style TargetType="{x:Type Button}">
    <Setter Property="Background" Value="Transparent" />
    <Style.Triggers>
        <DataTrigger Binding="{Binding }" Value="3">
            <Setter Property="Background" Value="Red" />
        </DataTrigger>
    </Style.Triggers>
</Style>