Silverlight -动态改变按钮文本的颜色
本文关键字：文本 颜色 按钮 改变 动态 Silverlight | 更新日期: 2023-09-27 17:53:27
我正在尝试使用ViewModel改变Silverlight表单上动态创建按钮的按钮文本颜色。我面临的问题是，当我改变按钮文本的颜色时，所有按钮都会受到影响。由于按钮是动态创建的，因此我无法对其进行控制。
有人建议我写一个ForegroundColor属性到模型，然后附加到按钮，我尝试了你在代码中看到的，但不能做太多关于它。
你能看到我在做什么，并帮助我与你的建议，因为我不确定，我正在做正确的方式。
感谢namespace Web.Models
{
[DataContract(IsReference = true)]
public class Sales
{
[DataMember]
public int SalesId { get; set; }
[DataMember]
public int ShowOrder { get; set; }
[DataMember]
public bool Active { get; set; }
[DataMember]
public bool Regurgitate { get; set; }
[DataMember]
public int ForegroundColor { get; set; }
public Sales(Salese result)
{
SalesId = result.SalesId;
ShowOrder = result.ShowOrder;
Active = result.Active;
Regurgitate = result.Regurgitate;
if (SalesId == 12)
{
var bytes = System.BitConverter.GetBytes(ForegroundColor);
Color btnColor = Color.FromArgb(bytes[3], bytes[2], bytes[1], bytes[0]);
SolidColorBrush myBrush = new SolidColorBrush(btnColor);
}
}
}
}
ViewModel
private Brush _foregroundColor = new SolidColorBrush(Colors.Black);
public override void Loaded()
{
OnMainOutcome();
}
public Brush ForegroundColor
{
get { return _foregroundColor; }
set
{
if (_foregroundColor == value) return;
_foregroundColor = value;
OnPropertyChanged("ForegroundColor");
}
}
private void OnMainOutcome()
{
var selectedSalesId = (int)OutcomeCommand.CommandParameter;
CurrentSubOutcomes = GetCurrentSubOutcomes(selectedSalesId);
foreach (var index in CurrentOutcomes)
{
if (index.OutcomeId == 12)
ForegroundColor = new SolidColorBrush(Colors.Red);
else
ForegroundColor = new SolidColorBrush(Colors.Black);
}
}
XAML编辑
<controls:ChildWindow.Resources>
<converters:NumericToColorConverter x:Key="NumericToColorConverter"/>
</controls:ChildWindow.Resources>
<ListBox Grid.Row="1" Height="Auto" MinHeight="200" Width="160" Margin="2,2,2,2" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" ItemsSource="{Binding Path=CurrentOutcomes}" Background="{x:Null}" BorderBrush="{x:Null}">
<ListBox.ItemTemplate>
<DataTemplate>
<Button Height="30" Width="150" HorizontalAlignment="Center" Content="{Binding Outcome}" CommandParameter="{Binding SalesOutcomeId }" Command="{Binding Source={StaticResource ViewModel}, Path=OutcomeCommand}" Foreground="{Binding Source={StaticResource ViewModel}, Converter={StaticResource NumericToColorConverter}, Path=ForegroundColor}" />
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
转换类NEW
using System;
using System.Windows.Data;
using System.Windows.Media;
using System.Windows;
namespace Converters
{
public class NumericToColorConverter : IValueConverter
{
static readonly SolidColorBrush RED_BRUSH = new SolidColorBrush(Colors.Red);
static readonly SolidColorBrush BLUE_BRUSH = new SolidColorBrush(Colors.Blue);
public object Convert(object value, Type targetType,
object parameter, System.Globalization.CultureInfo culture)
{
//Int32 id = System.Convert.ToInt32(value);
//LinearGradientBrush brush = new LinearGradientBrush();
//brush.StartPoint = new Point(0, 1);
//brush.EndPoint = new Point(0, 0);
//brush.GradientStops.Add(new GradientStop()
//{
// Color = Colors.White,
// Offset = 0
//});
//brush.GradientStops.Add(new GradientStop()
//{
// Color = Color.FromArgb(
// 200,
// System.Convert.ToByte((id * 103) % 256),
// System.Convert.ToByte((id * 157) % 256),
// System.Convert.ToByte((id * 233) % 256)
// ),
// Offset = 1
//});
//return brush;
var OutcomeId = (int)value;
if (OutcomeId == 12)
{
return RED_BRUSH;
}
else
{
return BLUE_BRUSH;
}
}
public object ConvertBack(object value, Type targetType, object parameter,
System.Globalization.CultureInfo culture)
{
throw new NotImplementedException();
}
}
}
您将Foreground绑定到StaticResource上的值，因此所有按钮都将绑定到相同的值。
你可以创建一个特定的"ButtonForegroundConverter"，或者你可以添加画笔属性到项目级视图模型，也有Outcome属性，你已经绑定到按钮的Content。然后按钮xaml看起来像这样:
<Button ...
Content="{Binding Outcome}"
Foreground="{Binding OutcomeForegroundBrush}"
...
/>
如果你直接绑定到一个实体，那么像那样添加属性不是一个好主意，所以上面的例子假设你有一个中间视图模型或控制器，你可以在上面添加这样的属性。
如果您选择使用转换器，它将看起来像这样:
<Button ...
Content="{Binding Outcome}"
Foreground="{Binding OutcomeId, Converter={StaticResource OutcomeToForegroundConverter}}"
...
/>
和转换器:
namespace MyConverters {
public sealed class OutcomeToColorConverter : IValueConverter {
public object Convert(object value, Type targetType, object parameter, CultureInfo culture) {
// We must have a valid integer value, double check bindings
if (value == null) {
throw new ArgumentNullException("value",
"Please make sure the value is not null.");
}
var OutcomeId = (int)value;
if (OutcomeId == XXX) {
return RED_BRUSH;
}
else {
return BLUE_BRUSH;
}
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) {
throw new NotImplementedException();
}
static readonly SolidColorBrush RED_BRUSH = new SolidColorBrush(Colors.Red);
static readonly SolidColorBrush BLUE_BRUSH = new SolidColorBrush(Colors.Blue);
}
}
记住声明资源:
<myconverters:OutcomeToForegroundConverter x:Key="OutcomeToForegroundConverter" />
您的列表框显示了Sales的列表，但是每个项目都是模板化的，以便将按钮前景绑定到VM中的单个属性。在Sales类中创建MyBrush属性并绑定到它。
namespace Web.Models
{
[DataContract(IsReference = true)]
public class Sales
{
[DataMember]
public int SalesId { get; set; }
[DataMember]
public int ShowOrder { get; set; }
[DataMember]
public bool Active { get; set; }
[DataMember]
public bool Regurgitate { get; set; }
[DataMember]
public int ForegroundColor { get; set; }
[DataMember]
public SolidColorBrush MyBrush { get; set; }
public Sales(Salese result)
{
SalesId = result.SalesId;
ShowOrder = result.ShowOrder;
Active = result.Active;
Regurgitate = result.Regurgitate;
if (SalesId == 12)
{
var bytes = System.BitConverter.GetBytes(ForegroundColor);
Color btnColor = Color.FromArgb(bytes[3], bytes[2], bytes[1], bytes[0]);
MyBrush = new SolidColorBrush(btnColor);
}
}
}
<ListBox Grid.Row="1" Height="Auto" MinHeight="200" Width="160" Margin="2,2,2,2" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" ItemsSource="{Binding Path=CurrentOutcomes}" Background="{x:Null}" BorderBrush="{x:Null}">
<ListBox.ItemTemplate>
<DataTemplate>
<Button Height="30" Width="150" HorizontalAlignment="Center" Content="{Binding Outcome}" CommandParameter="{Binding SalesOutcomeId }" Command="{Binding Source={StaticResource ViewModel}, Path=OutcomeCommand}" Foreground="{Binding MyBrush}" />
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>