如何在列表框的末端创建一个“更多”按钮并处理它

本文关键字:更多 一个 按钮 处理 列表 创建 | 更新日期: 2023-09-27 18:10:44

我在App.xaml上添加了这个资源

<Style x:Key="ListBoxMore" TargetType="ListBox">
    <Setter Property="Background" Value="Transparent"/>
    <Setter Property="Foreground" Value="{StaticResource PhoneForegroundBrush}"/>
    <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Disabled"/>
    <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/>
    <Setter Property="BorderThickness" Value="0"/>
    <Setter Property="BorderBrush" Value="Transparent"/>
    <Setter Property="Padding" Value="0"/>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="ListBox">
                <ScrollViewer x:Name="ScrollViewer" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Foreground="{TemplateBinding Foreground}" Padding="{TemplateBinding Padding}">
                    <StackPanel>
                        <ItemsPresenter/>
                        <Button Content="More" Name="moreButton"></Button>
                    </StackPanel>
                </ScrollViewer>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

我的列表框添加了这个样式

Style="{StaticResource ListBoxMore}"

它是有效的,但问题是…

如何在代码隐藏中获得此按钮?我需要给这个按钮添加属性并处理点击,我怎么得到这个按钮?

如何在列表框的末端创建一个“更多”按钮并处理它

一种常见的方法是创建一个自定义控件:

using System;
using System.Windows;
using System.Windows.Controls;
namespace WpfApplication2
{
    [TemplatePart(Name=PartMoreButtonName, Type=typeof(Button))]
    public class MyListBox : ListBox
    {
        private const string PartMoreButtonName = "PART_MoreButton";
        private Button _moreButton;
        public override void  OnApplyTemplate()
        {
            // unhook any handlers from _moreButton to prevent a memory leak
            _moreButton = GetTemplateChild(PartMoreButtonName) as Button;
            // do stuff with _moreButton, register handlers, etc.
        }
    }
}

注意在TemplatePartAttributeOnApplyTemplate的覆盖中都使用了字符串PART_MoreButton。该属性告诉控件的使用者,您期望他们提供的任何ControlTemplate必须具有类型为Button的控件,名称为PART_MoreButton:

<StackPanel>
    <l:MyListBox>
        <l:MyListBox.Style>
            <Style TargetType="ListBox">
                <Setter Property="Template">
                    <Setter.Value>
                        <ControlTemplate TargetType="ListBox">
                            <ScrollViewer x:Name="ScrollViewer">
                                <StackPanel>
                                    <ItemsPresenter/>
                                    <Button x:Name="PART_MoreButton" Content="More"></Button>
                                </StackPanel>
                            </ScrollViewer>
                        </ControlTemplate>
                    </Setter.Value>
                </Setter>
            </Style>
        </l:MyListBox.Style>
    </l:MyListBox>
</StackPanel>

当WPF为控件的每个实例膨胀模板时,将调用覆盖。此时,您可以访问按钮并注册事件处理程序等。希望这对你有帮助!