c# - 我的代码是否展示了良好的 WPF 实践？

Question

我正在开始一个 WPF 项目，并且刚刚完成了 UI 的基础，尽管它看起来非常复杂，所以我不确定我是否以正确的方式进行了布局。我不想开始开发后端并意识到我在前端做错了，让自己的生活更加艰难。

从

和 CSS 的背景来看，这有很大的不同，我真的想从一开始就把它做好。

本质上它是一个一周日历(7 天，周一至周日，默认为当前周。)最终将链接到一个数据库，如果我在这一天有某事的约会，它将显示在相关的一天。

我选择了 Grid 而不是 ListView，因为它的工作方式我不会将结果绑定(bind)到集合或任何类似的东西。相反，我将在 Canvas 中为每个事件的每一天(尚未放置在代码中)填写一个组合框，并在选择时显示更多详细信息。

XAML:

<Window x:Class="WOW_Widget.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:s="clr-namespace:System;assembly=mscorlib"
    xmlns:Extensions="clr-namespace:WOW_Widget"
    DataContext="{Binding RelativeSource={RelativeSource Self}}"
    Title="Window1" Height="239" Width="831">

    <Window.Resources>
        <LinearGradientBrush x:Key="NormalBrush" StartPoint="0,0" EndPoint="0,1">
            <GradientBrush.GradientStops>
                <GradientStopCollection>
                    <GradientStop Offset="1.0" Color="White"/>
                    <GradientStop Offset="0.0" Color="LightSlateGray"/>
                </GradientStopCollection>
            </GradientBrush.GradientStops>
        </LinearGradientBrush>
        <LinearGradientBrush x:Key="grdDayHeader" StartPoint="0,0" EndPoint="0,1">
            <GradientBrush.GradientStops>
                <GradientStopCollection>
                    <GradientStop Offset="0.0" Color="Peru" />
                    <GradientStop Offset="1.0" Color="White" />
                </GradientStopCollection>
            </GradientBrush.GradientStops>
        </LinearGradientBrush>
        <LinearGradientBrush x:Key="grdToday" StartPoint="0,0" EndPoint="0,1">
            <GradientBrush.GradientStops>
                <GradientStopCollection>
                    <GradientStop Offset="0.0" Color="LimeGreen"/>
                    <GradientStop Offset="1.0" Color="DarkGreen" />
                </GradientStopCollection>
            </GradientBrush.GradientStops>
        </LinearGradientBrush>
        <Style TargetType="{x:Type GridViewColumnHeader}">
            <Setter Property="Background" Value="Khaki" />
        </Style>
        <Style x:Key="DayHeader" TargetType="{x:Type Label}">
            <Setter Property="Background" Value="{StaticResource grdDayHeader}" />
            <Setter Property="Width" Value="111" />
            <Setter Property="Height" Value="25" />
            <Setter Property="HorizontalContentAlignment" Value="Center" />
        </Style>
        <Style x:Key="DayField">
            <Setter Property="Canvas.Width" Value="111" />
            <Setter Property="Canvas.Height" Value="60" />
            <Setter Property="Canvas.Background" Value="White" />
        </Style>
        <Style x:Key="Today">
            <Setter Property="Canvas.Background" Value="{StaticResource grdToday}" />
        </Style>
        <Style x:Key="CalendarColSpacer">
            <Setter Property="Canvas.Width" Value="1" />
            <Setter Property="Canvas.Background" Value="Black" />
        </Style>
        <Style x:Key="CalendarRowSpacer">
            <Setter Property="Canvas.Height" Value="1" />
            <Setter Property="Canvas.Background" Value="Black" />
        </Style>
    </Window.Resources>

    <Grid Background="{StaticResource NormalBrush}">
        <Border BorderBrush="Black" BorderThickness="1" Width="785" Height="86" Margin="12,12,12,104">
            <Canvas Height="86" Width="785" VerticalAlignment="Top">
                <Grid>
                    <Grid.ColumnDefinitions>
                        <ColumnDefinition />
                        <ColumnDefinition />
                        <ColumnDefinition />
                        <ColumnDefinition />
                        <ColumnDefinition />
                        <ColumnDefinition />
                        <ColumnDefinition />
                        <ColumnDefinition />
                        <ColumnDefinition />
                        <ColumnDefinition />
                        <ColumnDefinition />
                        <ColumnDefinition />
                        <ColumnDefinition />
                    </Grid.ColumnDefinitions>
                    <Grid.RowDefinitions>
                        <RowDefinition />
                        <RowDefinition />
                        <RowDefinition />
                    </Grid.RowDefinitions>
                    <Label Grid.Column="0" Grid.Row="0" Content="Monday" Style="{StaticResource DayHeader}" />
                    <Canvas Grid.Column="1" Grid.RowSpan="3" Grid.Row="0"  Style="{StaticResource CalendarColSpacer}" />
                    <Label Grid.Column="2" Grid.Row="0" Content="Tuesday" Style="{StaticResource DayHeader}" />
                    <Canvas Grid.Column="3" Grid.RowSpan="3" Grid.Row="0"  Style="{StaticResource CalendarColSpacer}" />
                    <Label Grid.Column="4" Grid.Row="0" Content="Wednesday" Style="{StaticResource DayHeader}" />
                    <Canvas Grid.Column="5" Grid.RowSpan="3" Grid.Row="0"  Style="{StaticResource CalendarColSpacer}" />
                    <Label Grid.Column="6" Grid.Row="0" Content="Thursday" Style="{StaticResource DayHeader}" />
                    <Canvas Grid.Column="7" Grid.RowSpan="3" Grid.Row="0"  Style="{StaticResource CalendarColSpacer}" />
                    <Label Grid.Column="8" Grid.Row="0" Content="Friday" Style="{StaticResource DayHeader}" />
                    <Canvas Grid.Column="9" Grid.RowSpan="3" Grid.Row="0"  Style="{StaticResource CalendarColSpacer}" />
                    <Label Grid.Column="10" Grid.Row="0" Content="Saturday" Style="{StaticResource DayHeader}" />
                    <Canvas Grid.Column="11" Grid.RowSpan="3" Grid.Row="0"  Style="{StaticResource CalendarColSpacer}" />
                    <Label Grid.Column="12" Grid.Row="0" Content="Sunday" Style="{StaticResource DayHeader}" />

                    <Canvas Grid.Column="0" Grid.ColumnSpan="13" Grid.Row="1" Style="{StaticResource CalendarRowSpacer}" />

                    <Canvas Grid.Column="0" Grid.Row="2" Margin="0" Style="{StaticResource DayField}">
                        <Label Name="lblMondayDate" />
                    </Canvas>
                    <Canvas Grid.Column="2" Grid.Row="2" Margin="0" Style="{StaticResource DayField}">
                        <Label Name="lblTuesdayDate" />
                    </Canvas>
                    <Canvas Grid.Column="4" Grid.Row="2" Margin="0" Style="{StaticResource DayField}">
                        <Label Name="lblWednesdayDate" />
                    </Canvas>
                    <Canvas Grid.Column="6" Grid.Row="2" Margin="0" Style="{StaticResource DayField}">
                        <Label Name="lblThursdayDate" />
                    </Canvas>
                    <Canvas Grid.Column="8" Grid.Row="2" Margin="0" Style="{StaticResource DayField}">
                        <Label Name="lblFridayDate" />
                    </Canvas>
                    <Canvas Grid.Column="10" Grid.Row="2" Margin="0" Style="{StaticResource DayField}">
                        <Label Name="lblSaturdayDate" />
                    </Canvas>
                    <Canvas Grid.Column="12" Grid.Row="2" Margin="0" Style="{StaticResource DayField}">
                        <Label Name="lblSundayDate" />
                    </Canvas>
                </Grid>
            </Canvas>
        </Border>
        <Canvas Height="86" HorizontalAlignment="Right" Margin="0,0,12,12" Name="canvas1" VerticalAlignment="Bottom" Width="198"></Canvas>        
    </Grid>
</Window>

CS:

public partial class Window1 : Window {
    private DateTime today = new DateTime();
    private Label[] Dates = new Label[7];
    public Window1() {
        DateTime start = today = DateTime.Now;
        int day = (int)today.DayOfWeek;
        while (day != 1) {
            start = start.Subtract(new TimeSpan(1, 0, 0, 0));
            day--;
        }
        InitializeComponent();
        Dates[0] = lblMondayDate;
        Dates[1] = lblTuesdayDate;
        Dates[2] = lblWednesdayDate;
        Dates[3] = lblThursdayDate;
        Dates[4] = lblFridayDate;
        Dates[5] = lblSaturdayDate;
        Dates[6] = lblSundayDate;
        FillWeek(start);
    }

    private void FillWeek(DateTime start) {
        for (int d = 0; d < Dates.Length; d++) {
            TimeSpan td = new TimeSpan(d, 0, 0, 0);
            DateTime _day = start.Add(td);
            if (_day.Date == today.Date) {
                Canvas dayCanvas = (Canvas)Dates[d].Parent;
                dayCanvas.Style = (Style)this.Resources["Today"];
            }
            Dates[d].Content = (int)start.Add(td).Day;
        }
    }
}

最佳答案

我会说，不，你的做法不对。您做的工作太多而让 WPF 做的太少。您应该使用数据绑定(bind)和 ItemsControl，并让 WPF 完成所有繁重的工作，以确定将东西放在哪里以及放什么东西。

1. 我在此示例中使用了 XmlDataProvider，因为这是演示如何在不编写代码的情况下使用数据绑定(bind)的最简单方法。您可能会构建一个 View 模型类，该类公开具有 Name 和 Date 属性的对象集合并绑定(bind)到该对象的一个​​实例。

2. 在 WPF 中使用 Canvas 和逐像素布局是一件坏事，这都是关于构建与分辨率无关的 UI。让布局引擎完成所有这些工作要好得多。

3. 并非所有看起来像网格的东西都需要使用 Grid 进行布局。如果将此网格布置为水平 StackPanel，则 XAML 会少得多。这使您不必费心处理行号和列号。我的布局使用 Grid 的唯一原因是根据内容设置边框大小。

这是我对您提供的内容进行的修改。在我看来，结果看起来与您的几乎相同，但 XAML 的数量大约是您的一半(不包括画笔)，而且更容易修改。

<Page
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  Background="{DynamicResource NormalBrush}">

  <Page.Resources>
       <XmlDataProvider x:Key="Days" XPath="Days">
        <x:XData>
          <Days xmlns="">
            <Day Name="Sunday" Date="03/14/2010"/>
            <Day Name="Monday" Date="03/15/2010"/>
            <Day Name="Tuesday" Date="03/16/2010"/>
            <Day Name="Wednesday" Date="03/17/2010"/>
            <Day Name="Thursday" Date="03/18/2010"/>
            <Day Name="Friday" Date="03/19/2010"/>
            <Day Name="Saturday" Date="03/20/2010"/>
          </Days>
        </x:XData>
       </XmlDataProvider>

        <LinearGradientBrush x:Key="NormalBrush" StartPoint="0,0" EndPoint="0,1">
            <GradientBrush.GradientStops>
                <GradientStopCollection>
                    <GradientStop Offset="1.0" Color="White"/>
                    <GradientStop Offset="0.0" Color="LightSlateGray"/>
                </GradientStopCollection>
            </GradientBrush.GradientStops>
        </LinearGradientBrush>

        <LinearGradientBrush x:Key="DayHeaderBrush" StartPoint="0,0" EndPoint="0,1">
            <GradientBrush.GradientStops>
                <GradientStopCollection>
                    <GradientStop Offset="0.0" Color="Peru" />
                    <GradientStop Offset="1.0" Color="White" />
                </GradientStopCollection>
            </GradientBrush.GradientStops>
        </LinearGradientBrush>        

  </Page.Resources>
        <Grid Margin="50">
          <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>            
          </Grid.RowDefinitions>
          <Grid.ColumnDefinitions>
            <ColumnDefinition Width="Auto"/>
          </Grid.ColumnDefinitions>
          <StackPanel Orientation="Horizontal">
            <ItemsControl ItemsSource="{Binding Source={StaticResource Days}, XPath=Day}">
              <ItemsControl.ItemsPanel>
                <ItemsPanelTemplate>
                  <StackPanel Orientation="Horizontal"/>
                </ItemsPanelTemplate>
              </ItemsControl.ItemsPanel>
              <ItemsControl.ItemTemplate>
                <DataTemplate>
                <StackPanel Orientation="Vertical" Background="White">
                    <Border BorderBrush="Black" BorderThickness="1,1,0,0" Background="{StaticResource DayHeaderBrush}">
                      <TextBlock Margin="30,10" HorizontalAlignment="Center" Text="{Binding XPath=@Name}"/>
                    </Border>
                    <Border BorderBrush="Black" BorderThickness="1,1,0,0">
                      <TextBlock Margin="30,10" Height="50" HorizontalAlignment="Center" Text="{Binding XPath=@Date}"/>
                    </Border>
                  </StackPanel>
                </DataTemplate>
              </ItemsControl.ItemTemplate>
            </ItemsControl>
            <Border BorderBrush="Black" BorderThickness="0,0,1,0"/>
          </StackPanel>
        </Grid>
</Page>

关于c# - 我的代码是否展示了良好的 WPF 实践？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/2431944/

Answer 1

我会说，不，你的做法不对。您做的工作太多而让 WPF 做的太少。您应该使用数据绑定(bind)和 ItemsControl，并让 WPF 完成所有繁重的工作，以确定将东西放在哪里以及放什么东西。

1. 我在此示例中使用了 XmlDataProvider，因为这是演示如何在不编写代码的情况下使用数据绑定(bind)的最简单方法。您可能会构建一个 View 模型类，该类公开具有 Name 和 Date 属性的对象集合并绑定(bind)到该对象的一个​​实例。

2. 在 WPF 中使用 Canvas 和逐像素布局是一件坏事，这都是关于构建与分辨率无关的 UI。让布局引擎完成所有这些工作要好得多。

3. 并非所有看起来像网格的东西都需要使用 Grid 进行布局。如果将此网格布置为水平 StackPanel，则 XAML 会少得多。这使您不必费心处理行号和列号。我的布局使用 Grid 的唯一原因是根据内容设置边框大小。

这是我对您提供的内容进行的修改。在我看来，结果看起来与您的几乎相同，但 XAML 的数量大约是您的一半(不包括画笔)，而且更容易修改。

<Page
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  Background="{DynamicResource NormalBrush}">

  <Page.Resources>
       <XmlDataProvider x:Key="Days" XPath="Days">
        <x:XData>
          <Days xmlns="">
            <Day Name="Sunday" Date="03/14/2010"/>
            <Day Name="Monday" Date="03/15/2010"/>
            <Day Name="Tuesday" Date="03/16/2010"/>
            <Day Name="Wednesday" Date="03/17/2010"/>
            <Day Name="Thursday" Date="03/18/2010"/>
            <Day Name="Friday" Date="03/19/2010"/>
            <Day Name="Saturday" Date="03/20/2010"/>
          </Days>
        </x:XData>
       </XmlDataProvider>

        <LinearGradientBrush x:Key="NormalBrush" StartPoint="0,0" EndPoint="0,1">
            <GradientBrush.GradientStops>
                <GradientStopCollection>
                    <GradientStop Offset="1.0" Color="White"/>
                    <GradientStop Offset="0.0" Color="LightSlateGray"/>
                </GradientStopCollection>
            </GradientBrush.GradientStops>
        </LinearGradientBrush>

        <LinearGradientBrush x:Key="DayHeaderBrush" StartPoint="0,0" EndPoint="0,1">
            <GradientBrush.GradientStops>
                <GradientStopCollection>
                    <GradientStop Offset="0.0" Color="Peru" />
                    <GradientStop Offset="1.0" Color="White" />
                </GradientStopCollection>
            </GradientBrush.GradientStops>
        </LinearGradientBrush>        

  </Page.Resources>
        <Grid Margin="50">
          <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>            
          </Grid.RowDefinitions>
          <Grid.ColumnDefinitions>
            <ColumnDefinition Width="Auto"/>
          </Grid.ColumnDefinitions>
          <StackPanel Orientation="Horizontal">
            <ItemsControl ItemsSource="{Binding Source={StaticResource Days}, XPath=Day}">
              <ItemsControl.ItemsPanel>
                <ItemsPanelTemplate>
                  <StackPanel Orientation="Horizontal"/>
                </ItemsPanelTemplate>
              </ItemsControl.ItemsPanel>
              <ItemsControl.ItemTemplate>
                <DataTemplate>
                <StackPanel Orientation="Vertical" Background="White">
                    <Border BorderBrush="Black" BorderThickness="1,1,0,0" Background="{StaticResource DayHeaderBrush}">
                      <TextBlock Margin="30,10" HorizontalAlignment="Center" Text="{Binding XPath=@Name}"/>
                    </Border>
                    <Border BorderBrush="Black" BorderThickness="1,1,0,0">
                      <TextBlock Margin="30,10" Height="50" HorizontalAlignment="Center" Text="{Binding XPath=@Date}"/>
                    </Border>
                  </StackPanel>
                </DataTemplate>
              </ItemsControl.ItemTemplate>
            </ItemsControl>
            <Border BorderBrush="Black" BorderThickness="0,0,1,0"/>
          </StackPanel>
        </Grid>
</Page>