我会删除 ListView 项目中带有按钮的项目,并使用 ListView 项目中的另一个按钮更改椭圆的颜色。
类产品代码:
class Product
{
public string Name { get; set; }
public double Price { get; set; }
}
xaml主页代码:
<Page
x:Class="ListViewTest.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:ListViewTest"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d" Loaded="Page_Loaded">
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<ListView x:Name="ListViewProducts"
ScrollViewer.HorizontalScrollBarVisibility="Disabled"
ScrollViewer.VerticalScrollBarVisibility="Auto"
FontSize="18"
BorderThickness="0"
Width="600"
Height="800"
HorizontalAlignment="Center"
VerticalAlignment="Center"
ItemsSource="{Binding LineItems}">
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel Margin="10">
<Grid HorizontalAlignment="Left" VerticalAlignment="Center" Margin="5,0,0,0">
<Ellipse x:Name="EllipseColor" HorizontalAlignment="Left" Height="20" Stroke="Black" VerticalAlignment="Top" Width="20" StrokeThickness="1"/>
</Grid>
<TextBlock Text="{Binding Name}" Margin="5,0,0,0"/>
<TextBlock Text="{Binding Price}" Margin="5,0,0,0"/>
<Button x:Name="btnRemove" Click="btnRemove_Click" Height="20" Width="60" Margin="5"/>
<Button x:Name="btnChangeColor" Click="btnChangeColor_Click" Height="20" Width="60" Margin="5"/>
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</Grid>
主页面背后的代码:
public sealed partial class MainPage : Page
{
public MainPage()
{
this.InitializeComponent();
}
private void Page_Loaded(object sender, RoutedEventArgs e)
{
ObservableCollection<Product> _listProduct = new ObservableCollection<Product>();
_listProduct = new ObservableCollection<Product>
{
new Product
{
Name = "Phone",
Price = 100
},
new Product
{
Name = "TV",
Price = 120
},
new Product
{
Name = "Computer",
Price = 80
},
new Product
{
Name = "Laptop",
Price = 250
},
new Product
{
Name = "Tablet",
Price = 150
},
new Product
{
Name = "Monitor",
Price = 200
},
};
ListViewProducts.ItemsSource = _listProduct;
}
private void btnRemove_Click(object sender, RoutedEventArgs e)
{
// Code to remove item
}
private void btnChangeColor_Click(object sender, RoutedEventArgs e)
{
// Code to color EllipseColor
}
}
使用 btnRemove 我会删除 ListView 项目,使用 btnChangeColor 我会把 EllipseColor 的填充颜色涂成红色,在 btnChangeColor_Click 中我会把项目的索引。
提前致谢。
最佳答案
在我看来,您遇到了几个问题。首先是您通过绑定(bind)到一个显然不存在的集合来设置您的 ListView
源,以及在 C# 中设置它。您应该将其移动到使用适当的绑定(bind)。例如,在 MainPage.xaml.cs
中:
private ObservableCollection<Product> _products = new ObservableCollection<Product>();
public ObservableCollection<Product> Products { get => _products; set => _products = value; }
然后绑定(bind)到它:
<ListView ItemsSource={x:Bind Products, Mode=OneWay} />
然后,在 btnRemove_Click
中,您可以从集合中删除该项目:
var product = (sender as Button).DataContext as Product;
Products.Remove(product);
至于为 Ellipse
着色,您实际上不应该在 C# 中这样做。相反,您的 Product
类应该有一个 Status
属性,然后更改该属性。
首先,您需要确保您的属性更改会发出火灾通知。
public class Product : INotifyPropertyChanged
{
private string _status;
public string Status
{
get => _status;
set
{
_status = value;
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(Status)));
}
}
public event PropertyChangedEventHandler PropertyChanged;
}
然后更改属性。
var product = (sender as Button).DataContext as Product;
product.Status = "invalid";
然后在您的 XAML 中,使用绑定(bind)转换器根据状态更改 Ellipse
的 Fill
属性。例如
using System;
using Windows.UI;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Media;
public class StatusConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, string language) =>
new SolidColorBrush(value.ToString() == "invalid" ? Colors.Red : Colors.Gray);
public object ConvertBack(object value, Type targetType, object parameter, string language) =>
throw new NotImplementedException();
}
然后您需要将转换器添加到您的资源中。
<Page...>
<Page.Resources>
<locationofyourconverter:StatusConverter x:Key="StatusConverter" />
</Page.Resources>
...
<Ellipse Fill={Binding Status, Mode=OneWay, Converter={StaticResource StatusConverter}} />
关于xaml - 更改 ListView 项目的颜色并删除项目 UWP,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/46099283/