Question

我正在尝试对我的网格进行一点点设计。我想根据每行中的信息为行着色。我在这次行动中遇到了这个令人讨厌的错误。此外，这在应用程序启动期间发生。这是我在WPF中的第一步，我正在尝试制作一些有用的记录器，但现在我已经碰到了巨大的墙。

错误： 在使用ItemsSource时，操作无效。使用ItemsControl.ItemsSource访问和修改元素。

值得一提的是，我使用静态列表作为ItemSource到网格。下面是我的一些代码。

<DataGrid DockPanel.Dock="Bottom" Height="Auto" ItemsSource="{Binding Source={x:Static Log:Logger.LogCollection}, Mode=OneWay}" FontSize="12" FontFamily="Segoe UI">
            <i:Interaction.Behaviors>
                <fw:ScrollGridView/>
            </i:Interaction.Behaviors>
            <Style TargetType="{x:Type DataGridRow}">
                <Style.Triggers>
                    <DataTrigger Binding="{Binding LogType}" Value="Info">
                        <Setter Property="Background" Value="Red" />
                    </DataTrigger>
                </Style.Triggers>
            </Style>
        </DataGrid>
    </DockPanel>

和班级

public static class Logger
{
    private static ObservableCollection<LogMessage> _logCollection = new ObservableCollection<LogMessage>();

    public static ObservableCollection<LogMessage> LogCollection
    {
        get { return Logger._logCollection; }
        set 
        { 
            if (_logCollection.Count > 500)
            {
                _logCollection.RemoveAt(_logCollection.Count - 1);
            }
            Logger._logCollection = value; 
        }
    }

    public static void Log(string message)
    {
        Log(LogType.Info, message, null);
    }

    public static void Log(LogType type, string message, string exception)
    {
        LogCollection.Add(new LogMessage { Type = type, Time = DateTime.Now, Message = message, Exception = exception });
    }
}

的LogMessage：

    public enum LogType
{
    Debug,
    Warning,
    Error,
    Info
}

public class LogMessage
{
    public LogType Type { get; set; }
    public DateTime Time { get; set; }
    public string Message { get; set; }
    public string Exception { get; set; }
}

谢谢！

Answer 1

请确保在DataGrid中DataGrid.Columns定义您的列，如下所示，而不是直接在DataGrid内，并在Style中定义DataGrid.Resource

     <DataGrid>
           <DataGrid.Resources>
              <Style TargetType="{x:Type DataGridRow}">
                   <Style.Triggers>
                      <DataTrigger Binding="{Binding LogType}" Value="Info">
                          <Setter Property="Background" Value="Red" />
                      </DataTrigger>
                </Style.Triggers>
                </Style>
          </DataGrid.Resources>
           <DataGrid.Columns>
                <DataGridTextColumn/>
            </DataGrid.Columns>

       </DataGrid>

Answer 2

它帮了!!!现在它看起来像这样：

<DataGrid DockPanel.Dock="Bottom" Height="Auto" ItemsSource="{Binding Source={x:Static Log:Logger.LogCollection}, Mode=OneWay}" FontSize="12" FontFamily="Segoe UI" AutoGenerateColumns="False">
            <i:Interaction.Behaviors>
                <fw:ScrollGridView/>
            </i:Interaction.Behaviors>
            <DataGrid.Resources>
            <Style TargetType="{x:Type DataGridRow}">
                <Style.Triggers>
                        <DataTrigger Binding="{Binding Type}" Value="Info">
                        <Setter Property="Background" Value="Red" />
                    </DataTrigger>
                </Style.Triggers>
            </Style>
            </DataGrid.Resources>
            <DataGrid.Columns>
                <DataGridTemplateColumn MinWidth="30" Header="Type">
                    <DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <Image Width="16"
                               Height="16"
                               Source="{Binding Path=Type,
                                                UpdateSourceTrigger=PropertyChanged,
                                                Converter={StaticResource ImageTypeConverter}}" />
                        </DataTemplate>
                    </DataGridTemplateColumn.CellTemplate>
                </DataGridTemplateColumn>
                <DataGridTextColumn Header="Time"
                                    Binding="{Binding Time}"/>
                <DataGridTextColumn Header="Message"
                                    Binding="{Binding Message}"
                                    Width="1200">
                    <DataGridTextColumn.ElementStyle>
                        <Style>
                            <Setter Property="TextBlock.TextWrapping" Value="Wrap" />
                        </Style>
                    </DataGridTextColumn.ElementStyle>
                </DataGridTextColumn>
                <DataGridTextColumn Header="Exception"
                                    Binding="{Binding Exception}"
                                    Width="1200">
                    <DataGridTextColumn.ElementStyle>
                        <Style>
                            <Setter Property="TextBlock.TextWrapping" Value="Wrap" />
                        </Style>
                    </DataGridTextColumn.ElementStyle>
                </DataGridTextColumn>
            </DataGrid.Columns>
        </DataGrid>
    </DockPanel>

我还有一个问题。在我完全添加DataGrid.Resources我的行为工作者之前，事件停止了。这很奇怪，因为我没有改变向我的网格源添加项目的方式。

    public class ScrollGridView : Behavior<DataGrid>
{
    protected override void OnAttached()
    {
        base.OnAttached();
        this.AssociatedObject.SelectionChanged  += new SelectionChangedEventHandler(AssociatedObject_SelectionChanged);
    }

    private void AssociatedObject_SelectionChanged(object sender, SelectionChangedEventArgs e)
    {
        if (sender is DataGrid)
        {
            DataGrid grid = (sender as DataGrid);
            if (grid.Items.Count > 0)
            {
                var border = VisualTreeHelper.GetChild(grid, 0) as Decorator;
                if (border != null)
                {
                    var scroll = border.Child as ScrollViewer;
                    if (scroll != null && !scroll.IsMouseOver) scroll.ScrollToEnd();
                }
            }
        }
    }

    protected override void OnDetaching()
    {
        base.OnDetaching();
        this.AssociatedObject.SelectionChanged -= new SelectionChangedEventHandler(AssociatedObject_SelectionChanged);
    }
}

样式化DataGrid行WPF异常

2 个答案: