我有一个来自WPF Toolkit的Chart控件。绑定到图表中使用的线系列的数据集是动态的，即，当我接收数据时，新点被添加到集合中。我注意到，因此，内存消耗正在增加。因此，我将行系列中显示的点数限制为20.以下是代码。
代码背后：
public partial class MainWindow : Window
{
ObservableCollection<ChartData> lineSeries1Data;
Thread MyThread;
LineSeries lineSeries;
ChartData objChartData;
Random r = new Random();
LineSeries temp;
public MainWindow()
{
InitializeComponent();
objChartData = new ChartData();
lineSeries1Data = new ObservableCollection<ChartData>();
AddLineSeries();
InitializeDataPoints();
MyThread = new Thread(new ThreadStart(StartChartDataSimulation));
}
private void AddLineSeries()
{
lineSeries = AddLineSeries(Brushes.Tomato);
lineSeries.DependentValuePath = "Value";
lineSeries.IndependentValuePath = "Name";
lineSeries.ItemsSource = lineSeries1Data;
simChart.Series.Add(lineSeries);
}
private LineSeries AddLineSeries(Brush lineColor)
{
temp = new LineSeries()
{
PolylineStyle = this.FindResource("PolylineStyle") as Style,
DataPointStyle = this.FindResource("LineDataPointStyle") as Style,
Style = this.FindResource("CommonLineSeries") as Style,
Tag = lineColor
};
return temp;
}
private void InitializeDataPoints()
{
lineSeries1Data.Add(new ChartData() { Name = DateTime.Now, Value = 0.0 });
Thread.Sleep(1000);
for (int i = 0; i < 2; i++)
{
lineSeries1Data.Add(new ChartData() { Name = DateTime.Now, Value = new Random().NextDouble() * 10 });
Thread.Sleep(1000);
}
}
public void StartChartDataSimulation()
{
int i = 0;
while (true)
{
Dispatcher.Invoke(new Action(() =>
{
objChartData.Name = DateTime.Now;
objChartData.Value = r.NextDouble() * 50;
lineSeries1Data.Add(objChartData);
if (lineSeries1Data.Count > 20)
{
lineSeries1Data.RemoveAt(0);
}
}));
Thread.Sleep(500);
}
}
private void btnStartCharting_Click(object sender, RoutedEventArgs e)
{
if (MyThread.ThreadState != ThreadState.Running)
{
MyThread.Start();
}
}
}
public class ChartData
{
DateTime _Name;
double _Value;
public DateTime Name
{
get
{
return _Name;
}
set
{
_Name = value;
}
}
public double Value
{
get
{
return _Value;
}
set
{
_Value = value;
}
}
}
XAML：
<Window x:Class="WpfChartExample.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:chrt="clr-namespace:System.Windows.Controls.DataVisualization.Charting;assembly=System.Windows.Controls.DataVisualization.Toolkit"
xmlns:datavis="clr-namespace:System.Windows.Controls.DataVisualization;assembly=System.Windows.Controls.DataVisualization.Toolkit"
Title="WPF Toolkit Dynamic Line Chart Example" Height="333" Width="1000" Closing="Window_Closing">
<Window.Resources>
<Style x:Key="PolylineStyle" TargetType="Polyline">
<Setter Property="StrokeThickness" Value="5" />
</Style>
<Style x:Key="LineDataPointStyle" TargetType="chrt:LineDataPoint">
<!--<Setter Property="Background" Value="#0077CC" />-->
<Setter Property="Background" >
<Setter.Value>
<Binding Path="Tag" RelativeSource="{RelativeSource AncestorType={x:Type chrt:LineSeries}}" />
</Setter.Value>
</Setter>
<Setter Property="BorderBrush" Value="White" />
<Setter Property="BorderThickness" Value="2" />
<Setter Property="IsTabStop" Value="False" />
<Setter Property="Height" Value="10" />
<Setter Property="Width" Value="10" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="chrt:LineDataPoint">
<Grid x:Name="Root" Opacity="1">
<ToolTipService.ToolTip>
<StackPanel Margin="2,2,2,2">
<ContentControl Content="{TemplateBinding IndependentValue}" ContentStringFormat="X-Value: {0:HH:mm:ss}"/>
<ContentControl Content="{TemplateBinding DependentValue}" ContentStringFormat="Y-Value: {0:###.###}"/>
</StackPanel>
</ToolTipService.ToolTip>
<Ellipse StrokeThickness="{TemplateBinding BorderThickness}" Stroke="{TemplateBinding BorderBrush}" Fill="{TemplateBinding Background}"/>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="CommonLineSeries" TargetType="chrt:LineSeries" BasedOn="{StaticResource {x:Type chrt:LineSeries}}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="chrt:LineSeries">
<Canvas x:Name="PlotArea">
<Polyline Points="{TemplateBinding Points}" Stroke="{Binding Tag, RelativeSource={RelativeSource AncestorType={x:Type chrt:LineSeries}}}" Style="{TemplateBinding PolylineStyle}"/>
</Canvas>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="LinearAxisStyle" TargetType="chrt:LinearAxis">
<Setter Property="GridLineStyle">
<Setter.Value>
<Style TargetType="Line">
<Setter Property="Stroke" Value="#20000000" />
</Style>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="NonLinearAxisStyle" TargetType="chrt:DateTimeAxis">
<Setter Property="GridLineStyle">
<Setter.Value>
<Style TargetType="Line">
<Setter Property="Stroke" Value="#20000000" />
</Style>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="DateTimeAxisLabelStyle" TargetType="chrt:DateTimeAxisLabel">
<Setter Property="StringFormat" Value="{}{0:mm:ss}" />
</Style>
<Style x:Key="ChartTitleStyle" TargetType="datavis:Title">
<Setter Property="Visibility" Value="Collapsed"/>
</Style>
</Window.Resources>
<Grid Name="grdMain">
<Grid.RowDefinitions>
<RowDefinition Height="6*" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<chrt:Chart x:Name="simChart" TitleStyle="{StaticResource ResourceKey=ChartTitleStyle}">
<chrt:Chart.LegendStyle>
<Style TargetType="datavis:Legend">
<Setter Property="Width" Value="0" />
</Style>
</chrt:Chart.LegendStyle>
<chrt:Chart.Axes>
<chrt:DateTimeAxis Name="xAxis" ShowGridLines="True" Orientation="X" Style="{StaticResource ResourceKey=NonLinearAxisStyle}" AxisLabelStyle="{StaticResource ResourceKey=DateTimeAxisLabelStyle}" />
<chrt:LinearAxis Orientation="Y" ShowGridLines="True" Style="{StaticResource ResourceKey=LinearAxisStyle}" />
</chrt:Chart.Axes>
<!--<chrt:LineSeries IsSelectionEnabled="True" PolylineStyle="{StaticResource ResourceKey=PolylineStyle}"
DataPointStyle="{StaticResource ResourceKey=LineDataPointStyle}"
ItemsSource="{Binding}"
IndependentValueBinding="{Binding Name}"
DependentValueBinding="{Binding Value}"
Tag="Red" Style="{StaticResource CommonLineSeries}">
</chrt:LineSeries>-->
</chrt:Chart>
<Button Name="btnStartCharting"
Grid.Row="1"
Width="Auto"
HorizontalAlignment="Right"
Margin="5"
Click="btnStartCharting_Click">
Start Charting
</Button>
</Grid>
在上面的代码中，当我删除第一个点时，图形刷新会受到影响。刷新变慢，有时会停止刷新。较旧的数据点也可以在图表上看到。有人可以指导我使用WPF Toolkit制作动态图表吗？