我正在开发一个WPF应用程序 . 这个应用程序使用OxyPlot chart control . 我让用户进行计算 . 用户可以以网格和图表形式查看结果 . 为了做到这一点,我有以下内容:
home.xaml
<DataGrid x:Name="resultDataGrid" ItemsSource="{Binding Items}">
<DataGrid.Columns>
<DataGridTextColumn Header="#" Binding="{Binding Number}" />
<DataGridTextColumn Header="Description" Binding="{Binding Description}" />
</DataGrid.Columns>
</DataGrid>
<oxy:Plot x:Name="resultGraph" Background="Transparent" Height="400" HorizontalContentAlignment="Stretch" VerticalAlignment="Stretch" Visibility="Collapsed">
<oxy:Plot.Series>
<oxy:LineSeries ItemsSource="{Binding Points}" MarkerType="Circle" Title="Result" />
</oxy:Plot.Series>
</oxy:Plot>
<StackPanel Orientation="Horizontal">
<Button x:Name="executeButton" Click="executeButton_Click" />
<Button x:Name="viewData" Click="viewData_Click" />
<Button x:Name="viewChart" Click="viewChart_Click" />
</StackPanel>
home.xaml.cs
public partial class Home: Page
{
private MyViewModel viewModel = null;
public Home()
{
InitializeComponent();
viewModel = new MyViewModel();
this.DataContext = viewModel;
}
private void executeButton_Click(object sender, RoutedEventArgs e) {
viewModel.Execute();
}
private void viewData_Click(object sender, RoutedEventArgs e)
{
resultDataGrid.Visibility = System.Windows.Visibility.Visible;
resultGraph.Visibility = System.Windows.Visibility.Collapsed;
}
private void viewChart_Click(object sender, RoutedEventArgs e)
{
resultDataGrid.Visibility = System.Windows.Visibility.Collapsed;
resultGraph.Visibility = System.Windows.Visibility.Visible;
}
}
MyViewModel.cs
public class MyViewModel : INotifyPropertyChanged
{
public Dictionary<int, string> Items{ get; set; }
public IList<DataPoint> Points{ get; set; }
public void Execute()
{
this.Items = new Dictionary<int, string>();
this.Points = new List<DataPoint>();
var randomNumber = GetRandomNumber();
for (var i=0; i<10; i++)
{
this.Items.Add((i+1), "Item #" + i);
var dataPoint = new DataPoint(i, (randomNumber*i));
this.Points.Add(dataPoint);
}
NotifyPropertyChanged("Items");
NotifyPropertyChanged("Points");
}
}
我的问题是,当用户点击"Execute"按钮时,数据会在 DataGrid
中刷新,这正是我所期待的 . 但是,如果图表首次可见,则只会刷新图表 . 换句话说,如果在 DataGrid
可见时单击"execute",则图表中的绘图点将变为陈旧 . 但是,如果我有 resultGraph
可见,我单击"Execute"点会按预期刷新 . 我不明白我做错了什么 . 任何帮助表示赞赏 .
3 回答
在您的ViewModel中创建
也不要忘记绑定InvalidateFlag
这应该可以解决问题
其实我找到了答案here:
更改后必须使绘图无效 . 有几个possibilities .
最简单的可能是一个脏的MVVM:在视图中订阅viewmodel
PropertyChanged
事件,检查Points
上升此事件是否已更改并使绘图无效 .通常,OxyPlot提供方法
PlotModel.InvalidatePlot(true)
以使用新输入数据刷新图表 . 编辑:哦,我看到你的ViewModel中没有PlotModel属性 . 我的回答需要这样一个属性,它也可以绑定到xaml .