根据项C＃Xamarin.Forms的值更改ListView项背景颜色

Question

I tried looking up the similar problem on the Internet but nothing seems to be like mine.

I have a ListView that displays list of records:

    <ListView x:Name="TavoloListView" HasUnevenRows="true" Grid.Row="2" SeparatorColor="Black"  
     SelectedItem="{Binding SelectedTavoloItem, Mode=TwoWay}" >
        <ListView.ItemTemplate>
            <DataTemplate>
                <ViewCell>
                    <Grid  ColumnSpacing="0" RowSpacing="0">
                        <Grid.RowDefinitions>
                            <RowDefinition Height="Auto" />

                        </Grid.RowDefinitions>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="*"/>
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="*"/>
                            <ColumnDefinition Width="*"/>
                        </Grid.ColumnDefinitions>
                        <BoxView x:Name="ItemsBackground" Grid.Column="0" Grid.ColumnSpan="6" Color="White" Opacity="0.5"/>
                        <Label Text="{Binding TavoloNo}" Grid.Row="0" Grid.Column="0" TextColor="Black" HorizontalOptions="Center"/>
                        <Label Text="{Binding CameraNo}" Grid.Row="0" Grid.Column="1" TextColor="Black" HorizontalOptions="Center"/>
                        <Label Text="{Binding Arrivo, StringFormat='\{0:dd/MM/yy}'}" Grid.Row="0" Grid.Column="2" TextColor="Black" HorizontalOptions="Center"/>
                        <Label Text="{Binding Partenza, StringFormat='\{0:dd/MM/yy}'}" Grid.Row="0" Grid.Column="3" TextColor="Black" HorizontalOptions="Center"/>
                        <Label Text="{Binding PersoneTot}" Grid.Row="0" Grid.Column="4" TextColor="Black" HorizontalOptions="Center"/>
                        <Label Text="{Binding Bambini, StringFormat='(\{0}\)'}" Grid.Row="0" Grid.Column="5" TextColor="Black" HorizontalOptions="Center"/>
                    </Grid>
                </ViewCell>
            </DataTemplate>
        </ListView.ItemTemplate>
    </ListView>

I need to change ItemsBackground BoxView 's Color based on the result of comparison of two Label s Arrivo and Partenza . Basically, on the page there is DatePicker named MainDatePicker . I want to compare the records' Arrivo and Partenza Date Values with the MainDatePicker.Date . If Arrivo == MainDatePicker.Date I want to change the ItemsBackground BoxView 's Color to Green. If Partenza matches the MainDatePicker.Date the ItemsBackground BoxView 's Color should be Red.

If none of the above is true, the color remains white.

Is it possible to achieve this?

Answer 1

you can set in side listViewBox colour like this `

<ListView Grid.Row="1" ItemsSource="{Binding BindListViewData}">
                <ListView.ItemTemplate>
                    <DataTemplate>
                        <ViewCell>
                            <ViewCell.View>
                                <BoxView>
                                    <BoxView.Triggers>
                                        <DataTrigger TargetType="BoxView" Binding="{Binding BindBoolValueFromModel}" Value="True">
                                            <Setter Property="BackgroundColor" Value="Green" />
                                        </DataTrigger>
                                        <DataTrigger TargetType="BoxView" Binding="{Binding BindBoolValueFromModel}" Value="False">
                                            <Setter Property="BackgroundColor" Value="Red" />
                                        </DataTrigger>
                                    </BoxView.Triggers>
                                </BoxView>
                            </ViewCell.View>
                        </ViewCell>
                    </DataTemplate>
                </ListView.ItemTemplate>
                </ListView>

`

Answer 2

Add new property in your SelectedTavoloItem, named for example color and when you initialize data source for TavoloListView just verify your condition

public void UpdateDataSourceForLIst()
{

List<SelectedTavoloItem> newListData=new List<SelectedTavoloItem>();
foreach(var item in DataSourceForList)
{
    if(Arrivo == MainDatePicker.Date)
    {
      item.color=green;
      newListData.Add(item);
    }else{
      item.color=red;
      newListData.Add(item);
    }

 }
DataSourceForList=newListData;
}

and when you bind list add this code in your box for background:

`<BoxView 
   x:Name="ItemsBackground" 
   Grid.Column="0" 
   Grid.ColumnSpan="6" 
   Color="{Binding color}" ////  bind new created property 
   Opacity="0.5"/>`