『聚合』 WPF开发分页控件：实现可定制化分页功能及实现原理解析

概要

　　本文将详细介绍如何使用WPF（Windows Presentation Foundation）开发一个分页控件，并深入解析其实现原理。我们将通过使用XAML和C#代码相结合的方式构建分页控件，并确保它具有高度的可定制性，以便在不同的应用场景中满足各种需求。

一.简介

　　分页控件是在许多应用程序中常见的一种界面元素，特别是在数据展示的场景中。它允许用户浏览大量数据，并根据需要切换到不同的数据页。

二.需求分析

　　我们首先来分析一下一个分页控件的基本构成。

2.1 总条目数（TotalItems）

　　表示总数据量。

2.2 每页条目数（PageSize）

　　表示每页显示的条目数。

2.3 总页数（PageCount）

　　表示根据总条目数与每页条目数计算出来的页数。

2.4 分页/页码按钮数量（PageNumberCount）

　　分页控件中可以点击的页码按钮。

2.5 当前页（CurrentPage）

　　当前显示的页，通常高亮显示。

三.控件命令和事件

3.1 页面跳转命令（GoToPageCommand）

　　该命令用于在XAML代码中触发页面跳转操作。

3.2当前页变更事件

　　当CurrentPage参数改变后触发该事件，通常在该事件中执行数据查询操作。

四.代码实现

　　通过以上原理分析，我们提取出了分页控件需要包含的基本要素，下面我们通过这些信息来组装成一个分页控件。

 1 <Style TargetType="{x:Type local:Pager}">
 2     <Setter Property="Template">
 3         <Setter.Value>
 4             <ControlTemplate TargetType="{x:Type local:Pager}">
 5                 <Border Background="{TemplateBinding Background}"
 6                             BorderBrush="{TemplateBinding BorderBrush}"
 7                             BorderThickness="{TemplateBinding BorderThickness}">
 8                     <StackPanel Orientation="Horizontal" ClipToBounds="True">
 9                         <Button Command="{x:Static local:Pager.GoToPageCommand}" CommandParameter="1" Margin="0,0,5,0" Content="首页"></Button>
10                         <Button Command="{x:Static local:Pager.GoToPageCommand}" CommandParameter="-" Margin="5,0" Content="上一页"></Button>
11                         <ItemsControl ItemsSource="{TemplateBinding PageButtons}">
12                             <ItemsControl.ItemsPanel>
13                                 <ItemsPanelTemplate>
14                                     <StackPanel Orientation="Horizontal"/>
15                                 </ItemsPanelTemplate>
16                             </ItemsControl.ItemsPanel>
17                             <ItemsControl.ItemTemplate>
18                                 <DataTemplate>
19                                     <ToggleButton MinWidth="{Binding RelativeSource={RelativeSource Mode=Self},Path=ActualHeight}"              
20                                                       Content="{Binding Page}"                        
21                                                       IsChecked="{Binding IsCurrentPage}"                        
22                                                       Command="{x:Static local:Pager.GoToPageCommand}"
23                                                       CommandParameter="{Binding Page}"
24                                                       Margin="5,0"/>
25                                 </DataTemplate>
26                             </ItemsControl.ItemTemplate>
27                         </ItemsControl>
28                         <Button Command="{x:Static local:Pager.GoToPageCommand}" CommandParameter="+" Margin="5,0" Content="下一页"></Button>
29                         <Button Command="{x:Static local:Pager.GoToPageCommand}" CommandParameter="尾页" Margin="5,0,0,0" Content="{DynamicResource LastPage}"></Button>
30                     </StackPanel>
31                 </Border>
32             </ControlTemplate>
33         </Setter.Value>
34     </Setter> 
35 </Style>

五.多样化需求

　　在不同的业务场景下需要的分页控件可能不尽相同，那么如何来满足多样化需求呢，答案就是自定义控件模板。下面演示几种常见的分页控件如何实现。

 1 <Style TargetType="{x:Type Controls:Pager}">
 2     <Setter Property="Template">
 3         <Setter.Value>
 4             <ControlTemplate TargetType="{x:Type Controls:Pager}">
 5                 <Border Background="{TemplateBinding Background}"
 6                             BorderBrush="{TemplateBinding BorderBrush}"
 7                             BorderThickness="{TemplateBinding BorderThickness}">
 8                     <StackPanel Orientation="Horizontal" ClipToBounds="True">
 9                         <Button Command="{x:Static Controls:Pager.GoToPageCommand}" CommandParameter="-" Margin="5,0" Content="{DynamicResource PreviousPage}"></Button>
10                         <Button Command="{x:Static Controls:Pager.GoToPageCommand}" CommandParameter="+" Margin="5,0" Content="{DynamicResource NextPage}"></Button>
11                     </StackPanel>
12                 </Border>
13             </ControlTemplate>
14         </Setter.Value>
15     </Setter>
16 </Style>

只需要“首页”、“上一页”、“下一页”、“尾页”的情况。

 1 <Style TargetType="{x:Type Controls:Pager}">
 2     <Setter Property="Template">
 3         <Setter.Value>
 4             <ControlTemplate TargetType="{x:Type Controls:Pager}">
 5                 <Border Background="{TemplateBinding Background}"
 6                             BorderBrush="{TemplateBinding BorderBrush}"
 7                             BorderThickness="{TemplateBinding BorderThickness}">
 8                     <StackPanel Orientation="Horizontal" ClipToBounds="True">
 9                         <Button Command="{x:Static Controls:Pager.GoToPageCommand}" CommandParameter="1" Margin="0,0,5,0" Content="{DynamicResource FirstPage}"></Button>
10                         <Button Command="{x:Static Controls:Pager.GoToPageCommand}" CommandParameter="-" Margin="5,0" Content="{DynamicResource PreviousPage}"></Button>
11                         <Button Command="{x:Static Controls:Pager.GoToPageCommand}" CommandParameter="+" Margin="5,0" Content="{DynamicResource NextPage}"></Button>
12                         <Button Command="{x:Static Controls:Pager.GoToPageCommand}" CommandParameter="{TemplateBinding PageCount}" Margin="5,0,0,0" Content="{DynamicResource LastPage}"></Button>
13                     </StackPanel>
14                 </Border>
15             </ControlTemplate>
16         </Setter.Value>
17     </Setter>
18 </Style>

数字显示“首页”、“尾页”的情况。

 1 <Style TargetType="{x:Type Controls:Pager}">
 2     <Setter Property="Template">
 3         <Setter.Value>
 4             <ControlTemplate TargetType="{x:Type Controls:Pager}">
 5                 <Border Background="{TemplateBinding Background}"
 6                             BorderBrush="{TemplateBinding BorderBrush}"
 7                             BorderThickness="{TemplateBinding BorderThickness}">
 8                     <StackPanel Orientation="Horizontal" ClipToBounds="True">
 9                         <Button Command="{x:Static Controls:Pager.GoToPageCommand}" 
10                                         CommandParameter="1" 
11                                         Content="1"
12                                         MinWidth="{Binding RelativeSource={RelativeSource Mode=Self},Path=ActualHeight}" 
13                                         Margin="0,0,5,0">
14                             <Button.Visibility>
15                                 <MultiBinding Converter="{StaticResource PageNumberToVisibilityConverter}" ConverterParameter="First">
16                                     <Binding RelativeSource="{RelativeSource AncestorType=Controls:Pager}" Path="CurrentPage"/>
17                                     <Binding RelativeSource="{RelativeSource AncestorType=Controls:Pager}" Path="PageNumberCount"/>
18                                     <Binding RelativeSource="{RelativeSource AncestorType=Controls:Pager}" Path="PageCount"/>
19                                 </MultiBinding>
20                             </Button.Visibility>
21                         </Button>
22                         <Button IsEnabled="False" Margin="5,0" MinWidth="{Binding RelativeSource={RelativeSource Mode=Self},Path=ActualHeight}" Content="...">
23                             <Button.Visibility>
24                                 <MultiBinding Converter="{StaticResource PageNumberToVisibilityConverter}" ConverterParameter="First">
25                                     <Binding RelativeSource="{RelativeSource AncestorType=Controls:Pager}" Path="CurrentPage"/>
26                                     <Binding RelativeSource="{RelativeSource AncestorType=Controls:Pager}" Path="PageNumberCount"/>
27                                     <Binding RelativeSource="{RelativeSource AncestorType=Controls:Pager}" Path="PageCount"/>
28                                 </MultiBinding>
29                             </Button.Visibility>
30                         </Button>
31                         <Button Command="{x:Static Controls:Pager.GoToPageCommand}" CommandParameter="-" Margin="5,0" Content="{DynamicResource PreviousPage}"></Button>
32                         <ItemsControl ItemsSource="{TemplateBinding PageButtons}">
33                             <ItemsControl.ItemsPanel>
34                                 <ItemsPanelTemplate>
35                                     <StackPanel Orientation="Horizontal"/>
36                                 </ItemsPanelTemplate>
37                             </ItemsControl.ItemsPanel>
38                             <ItemsControl.ItemTemplate>
39                                 <DataTemplate>
40                                     <ToggleButton MinWidth="{Binding RelativeSource={RelativeSource Mode=Self},Path=ActualHeight}" 
41                         Content="{Binding Page}" 
42                         Margin="5,0" 
43                         IsChecked="{Binding IsCurrentPage}"
44                         Command="{x:Static Controls:Pager.GoToPageCommand}"
45                         CommandParameter="{Binding Page}"/>
46                                 </DataTemplate>
47                             </ItemsControl.ItemTemplate>
48                         </ItemsControl>
49                         <Button Command="{x:Static Controls:Pager.GoToPageCommand}" CommandParameter="+" Margin="5,0" Content="{DynamicResource NextPage}"></Button>
50                         <Button IsEnabled="False" Margin="5,0" MinWidth="{Binding RelativeSource={RelativeSource Mode=Self},Path=ActualHeight}" Content="...">
51                             <Button.Visibility>
52                                 <MultiBinding Converter="{StaticResource PageNumberToVisibilityConverter}">
53                                     <Binding RelativeSource="{RelativeSource AncestorType=Controls:Pager}" Path="CurrentPage"/>
54                                     <Binding RelativeSource="{RelativeSource AncestorType=Controls:Pager}" Path="PageNumberCount"/>
55                                     <Binding RelativeSource="{RelativeSource AncestorType=Controls:Pager}" Path="PageCount"/>
56                                 </MultiBinding>
57                             </Button.Visibility>
58                         </Button>
59                         <Button Command="{x:Static Controls:Pager.GoToPageCommand}" 
60                                         CommandParameter="{Binding RelativeSource={RelativeSource AncestorType=Controls:Pager},Path=PageCount}" 
61                                         Content="{Binding RelativeSource={RelativeSource AncestorType=Controls:Pager},Path=PageCount}" 
62                                         MinWidth="{Binding RelativeSource={RelativeSource Mode=Self},Path=ActualHeight}"
63                                         Margin="5,0,0,0">
64                             <Button.Visibility>
65                                 <MultiBinding Converter="{StaticResource PageNumberToVisibilityConverter}">
66                                     <Binding RelativeSource="{RelativeSource AncestorType=Controls:Pager}" Path="CurrentPage"/>
67                                     <Binding RelativeSource="{RelativeSource AncestorType=Controls:Pager}" Path="PageNumberCount"/>
68                                     <Binding RelativeSource="{RelativeSource AncestorType=Controls:Pager}" Path="PageCount"/>
69                                 </MultiBinding>
70                             </Button.Visibility>
71                         </Button>
72 
73                         <StackPanel Orientation="Horizontal" Margin="5,0,0,0">
74                             <TextBlock Text="转到" VerticalAlignment="Center"/>
75                             <TextBox x:Name="tbox_Page" Width="40" Margin="5,0" Padding="5" HorizontalContentAlignment="Center" VerticalAlignment="Center"/>
76                             <TextBlock Text="页" VerticalAlignment="Center"/>
77                             <Button Margin="5,0,0,0" Command="{x:Static Controls:Pager.GoToPageCommand}" CommandParameter="{Binding ElementName=tbox_Page,Path=Text}">确定</Button>
78                         </StackPanel>
79                     </StackPanel>
80                 </Border>
81             </ControlTemplate>
82         </Setter.Value>
83     </Setter>
84 </Style>

可以调整每页显示条目，可以显示总页数，可以跳转到指定页的情况。

 1 <Style TargetType="{x:Type Controls:Pager}">
 2     <Setter Property="Template">
 3         <Setter.Value>
 4             <ControlTemplate TargetType="{x:Type Controls:Pager}">
 5                 <Border Background="{TemplateBinding Background}"
 6                             BorderBrush="{TemplateBinding BorderBrush}"
 7                             BorderThickness="{TemplateBinding BorderThickness}">
 8                     <StackPanel Orientation="Horizontal" ClipToBounds="True">
 9                         <Button Command="{x:Static Controls:Pager.GoToPageCommand}" CommandParameter="1" Margin="0,0,5,0" MinWidth="{Binding RelativeSource={RelativeSource Mode=Self},Path=ActualHeight}" Content="{DynamicResource FirstPage}"></Button>
10                         <Button Command="{x:Static Controls:Pager.GoToPageCommand}" CommandParameter="-" Margin="5,0" MinWidth="{Binding RelativeSource={RelativeSource Mode=Self},Path=ActualHeight}" Content="{DynamicResource PreviousPage}"></Button>
11                         <ItemsControl ItemsSource="{TemplateBinding PageButtons}">
12                             <ItemsControl.ItemsPanel>
13                                 <ItemsPanelTemplate>
14                                     <StackPanel Orientation="Horizontal"/>
15                                 </ItemsPanelTemplate>
16                             </ItemsControl.ItemsPanel>
17                             <ItemsControl.ItemTemplate>
18                                 <DataTemplate>
19                                     <ToggleButton MinWidth="{Binding RelativeSource={RelativeSource Mode=Self},Path=ActualHeight}" 
20                         Content="{Binding Page}" 
21                         Margin="5,0" 
22                         IsChecked="{Binding IsCurrentPage}"
23                         Command="{x:Static Controls:Pager.GoToPageCommand}"
24                         CommandParameter="{Binding Page}"/>
25                                 </DataTemplate>
26                             </ItemsControl.ItemTemplate>
27                         </ItemsControl>
28                         <Button Command="{x:Static Controls:Pager.GoToPageCommand}" CommandParameter="+" Margin="5,0" MinWidth="{Binding RelativeSource={RelativeSource Mode=Self},Path=ActualHeight}" Content="{DynamicResource NextPage}"></Button>
29                         <Button Command="{x:Static Controls:Pager.GoToPageCommand}" CommandParameter="{TemplateBinding PageCount}" Margin="5,0,0,0" MinWidth="{Binding RelativeSource={RelativeSource Mode=Self},Path=ActualHeight}" Content="{DynamicResource LastPage}"></Button>
30                         <StackPanel Orientation="Horizontal" Margin="5,0,0,0">
31                             <TextBlock Margin="0,0,5,0" Text="每页" VerticalAlignment="Center"/>
32                             <ComboBox Margin="5,0" SelectedIndex="0" VerticalContentAlignment="Center" SelectedItem="{Binding RelativeSource={RelativeSource AncestorType=Controls:Pager},Path=PageSize,Mode=OneWayToSource}">
33                                 <sys:Int32>5</sys:Int32>
34                                 <sys:Int32>10</sys:Int32>
35                                 <sys:Int32>15</sys:Int32>
36                                 <sys:Int32>20</sys:Int32>
37                             </ComboBox>
38                             <TextBlock Text="条" VerticalAlignment="Center" Margin="5,0"/>
39                             <TextBlock VerticalAlignment="Center" Margin="5,0">
40                                         <Run Text="共"/>
41                                         <Run Text="{Binding RelativeSource={RelativeSource AncestorType=Controls:Pager},Path=PageCount}"/>
42                                         <Run Text="页"/>
43                             </TextBlock>
44                             <TextBlock Text="转到" VerticalAlignment="Center"/>
45                             <TextBox x:Name="tbox_Page" Width="40" Margin="5,0" Padding="5" HorizontalContentAlignment="Center" VerticalAlignment="Center"/>
46                             <TextBlock Text="页" VerticalAlignment="Center"/>
47                             <Button Margin="5,0,0,0" Command="{x:Static Controls:Pager.GoToPageCommand}" CommandParameter="{Binding ElementName=tbox_Page,Path=Text}">确定</Button>
48                         </StackPanel>
49                     </StackPanel>
50                 </Border>
51             </ControlTemplate>
52         </Setter.Value>
53     </Setter>
54 </Style>

除了修改模板实现不同的形态的分页控件以外，还可以用图标替换掉“首页”、“上一页”、“下一页”、”尾页”等文字。

六.个性化控件外观

　　项目中的界面外观可能多种多样，有自己写的控件样式，也有使用第三方UI库的样式，如何跟它们搭配使用呢。

自定义控件样式

1 <Style TargetType="Button">
2     <Setter Property="Padding" Value="5"/>
3     <Setter Property="Background" Value="Red"/>
4 </Style>
5 <Style TargetType="ToggleButton">
6     <Setter Property="Padding" Value="5"/>
7     <Setter Property="Background" Value="Red"/>
8 </Style>

使用第三方UI库

1.HandyControl

1 <ResourceDictionary>
2     <ResourceDictionary.MergedDictionaries>
3         <ResourceDictionary Source="pack://application:,,,/HandyControl;component/Themes/SkinDefault.xaml" />
4         <ResourceDictionary Source="pack://application:,,,/HandyControl;component/Themes/Theme.xaml" />
5     </ResourceDictionary.MergedDictionaries>
6 </ResourceDictionary>

2.MaterialDesign

1 <ResourceDictionary>
2     <ResourceDictionary.MergedDictionaries>
3         <materialDesign:CustomColorTheme BaseTheme="Light" PrimaryColor="#FF3561FF" SecondaryColor="#FF3561FF" />
4         <ResourceDictionary Source="pack://application:,,,/MaterialDesignThemes.Wpf;component/Themes/MaterialDesignTheme.Defaults.xaml" />
5     </ResourceDictionary.MergedDictionaries>
6 </ResourceDictionary>