WPF ListView對象DataTrigger

Question

我正在嘗試基於listview項目對象的數據字段在listview項目內部設置矩形的樣式。

為了返回布爾值，我正在將整數從daydata.workload轉換為使用IValueConverter的布爾值。

我也沒有例外，矩形僅不受DataTrigger的影響。 其他樣式規則效果很好。

<Window.Resources>
    <cv:numConverter x:Key="capacityConverter" />
<Window.Resources>

-

<ListView Name="weekView" ItemsSource="{Binding dayList}" ItemTemplate="{StaticResource DefaultTemplate}" >
            <ListView.Resources>
                <Style TargetType="Rectangle" x:Key="capacityBG">

                    <Setter Property="Stroke" Value="#FFE2E2E2" />
                    <Setter Property="Width" Value="180" />
                    <Setter Property="Height" Value="10" />
                    <Style.Triggers>
                        <DataTrigger Binding="{Binding Path=dayList.workload, Converter={StaticResource capacityConverter}, ConverterParameter=12}">
                            <DataTrigger.Value>true</DataTrigger.Value>
                            <Setter Property="Fill" Value="Red"/>
                        </DataTrigger>

                    </Style.Triggers>
                </Style>
            </ListView.Resources>
            <ListView.ItemsPanel>
                <ItemsPanelTemplate>
                    <StackPanel Orientation="Horizontal"></StackPanel>
                </ItemsPanelTemplate>
            </ListView.ItemsPanel>
            <ListView.ItemContainerStyle>
                <Style TargetType="{x:Type ListViewItem}">
                    <Setter Property="Background" Value="Transparent" />
                    <Setter Property="Template">
                        <Setter.Value>
                            <ControlTemplate TargetType="{x:Type ListViewItem}">
                                <ContentPresenter />
                            </ControlTemplate>
                        </Setter.Value>
                    </Setter>
                </Style>
            </ListView.ItemContainerStyle>
        </ListView>

-

<Rectangle Style="{DynamicResource capacityBG}" VerticalAlignment="Top" Grid.Row="0" />

-

  public class numConverter : IValueConverter
{

    object IValueConverter.Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return ((int)value) > val;
    }

    object IValueConverter.ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }

    public int val { get; set; }
}

-

public class dayData
{
    public DateTime date { get; set; }
    public int workload { get; set; }

    public List<job> jobs { get; set; }
}

Answer 1

這里的問題是，為轉換器參數輸入的值和數據觸發值被視為字符串。 您需要為以下每個值指定類型，如下所示：

xmlns:sys="clr-namespace:System;assembly=mscorlib"

    <Style.Triggers>
            <DataTrigger>
                <DataTrigger.Binding>
                    <Binding Path="WorkLoad" Converter="{StaticResource capacityConverter}">
                        <Binding.ConverterParameter>
                            <sys:Int32>12</sys:Int32>
                        </Binding.ConverterParameter>
                    </Binding>
                </DataTrigger.Binding>
                <DataTrigger.Value>
                    <sys:Boolean>true</sys:Boolean>
                </DataTrigger.Value>
                <Setter Property="Fill" Value="Red"/>
            </DataTrigger>
    </Style.Triggers>

然后，您可以將轉換器參數轉換為int進行比較。

    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return (int)value > (int)parameter;
    }