我已经通过使用winforms创建了它,只需添加permon类并下载一些实时的dasboards,但是我发现在WPF中这很困难
答案 0 :(得分:2)
有a lot of tools允许在WPF中绘制各种图形。
但是由于我没有找到任何手动图形绘制实现,因此创建了示例-如何使用MVVM编程模式在WPF中绘制图形。
为了正确,轻松地实现MVVM,我将使用以下两个类。
NotifyPropertyChanged.cs -通知用户界面更改。
public class NotifyPropertyChanged : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
=> PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
RelayCommand.cs -为便于使用的命令(对于Button
)
public class RelayCommand : ICommand
{
private readonly Action<object> _execute;
private readonly Predicate<object> _canExecute;
public event EventHandler CanExecuteChanged
{
add => CommandManager.RequerySuggested += value;
remove => CommandManager.RequerySuggested -= value;
}
public RelayCommand(Action<object> execute, Predicate<object> canExecute = null)
=> (_execute, _canExecute) = (execute, canExecute);
public bool CanExecute(object parameter)
=> _canExecute == null || _canExecute(parameter);
public void Execute(object parameter)
=> _execute(parameter);
}
由于图形由不断旋转的大量点组成,因此我实现了仅具有一种方法Push()
的Round-Robin Collection。
RoundRobinCollection.cs
public class RoundRobinCollection : NotifyPropertyChanged
{
private readonly List<float> _values;
public IReadOnlyList<float> Values => _values;
public RoundRobinCollection(int amount)
{
_values = new List<float>();
for (int i = 0; i < amount; i++)
_values.Add(0F);
}
public void Push(float value)
{
_values.RemoveAt(0);
_values.Add(value);
OnPropertyChanged(nameof(Values));
}
}
用于查看标记
PolygonConverter.cs
public class PolygonConverter : IMultiValueConverter
{
public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
{
PointCollection points = new PointCollection();
if (values.Length == 3 && values[0] is IReadOnlyList<float> dataPoints && values[1] is double width && values[2] is double height)
{
points.Add(new Point(0, height));
points.Add(new Point(width, height));
double step = width / (dataPoints.Count - 1);
double position = width;
for (int i = dataPoints.Count - 1; i >= 0; i--)
{
points.Add(new Point(position, height - height * dataPoints[i] / 100));
position -= step;
}
}
return points;
}
public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture) => null;
}
包含应用程序所有业务逻辑的主类
public class MainViewModel : NotifyPropertyChanged
{
private bool _graphEnabled;
private float _lastCpuValue;
private ICommand _enableCommand;
public RoundRobinCollection ProcessorTime { get; }
public string ButtonText => GraphEnabled ? "Stop" : "Start";
public bool GraphEnabled
{
get => _graphEnabled;
set
{
if (value != _graphEnabled)
{
_graphEnabled = value;
OnPropertyChanged();
OnPropertyChanged(nameof(ButtonText));
if (value)
ReadCpu();
}
}
}
public float LastCpuValue
{
get => _lastCpuValue;
set
{
_lastCpuValue = value;
OnPropertyChanged();
}
}
public ICommand EnableCommand => _enableCommand ?? (_enableCommand = new RelayCommand(parameter =>
{
GraphEnabled = !GraphEnabled;
}));
private async void ReadCpu()
{
try
{
using (PerformanceCounter cpuCounter = new PerformanceCounter("Processor", "% Processor Time", "_Total"))
{
while (GraphEnabled)
{
LastCpuValue = cpuCounter.NextValue();
ProcessorTime.Push(LastCpuValue);
await Task.Delay(1000);
}
}
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
}
}
public MainViewModel()
{
ProcessorTime = new RoundRobinCollection(100);
}
}
Disclamer:不建议使用async void
来制造async
的方法,但是这里的用法是安全的,因为任何可能的Exception
都将在内部处理。有关async void
不好的原因的更多信息,请参阅文档Asynchronous Programming。
应用程序的整个UI标记
<Window x:Class="CpuUsageExample.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:CpuUsageExample"
mc:Ignorable="d"
Title="MainWindow" Height="400" Width="800" >
<Window.DataContext>
<local:MainViewModel/><!-- attach View Model -->
</Window.DataContext>
<Window.Resources>
<local:PolygonConverter x:Key="PolygonConverter"/><!-- attach Converter -->
</Window.Resources>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition/>
</Grid.RowDefinitions>
<WrapPanel>
<Button Margin="5" Padding="10,0" Content="{Binding ButtonText}" Command="{Binding EnableCommand}"/>
<TextBlock Margin="5" Text="CPU:"/>
<TextBlock Margin="0, 5" Text="{Binding LastCpuValue, StringFormat=##0.##}" FontWeight="Bold"/>
<TextBlock Margin="0, 5" Text="%" FontWeight="Bold"/>
</WrapPanel>
<Border Margin="5" Grid.Row="1" BorderThickness="1" BorderBrush="Gray" SnapsToDevicePixels="True">
<Canvas ClipToBounds="True">
<Polygon Stroke="CadetBlue" Fill="AliceBlue">
<Polygon.Resources>
<Style TargetType="Polygon">
<Setter Property="Points">
<Setter.Value>
<MultiBinding Converter="{StaticResource PolygonConverter}">
<Binding Path="ProcessorTime.Values"/>
<Binding Path="ActualWidth" RelativeSource="{RelativeSource AncestorType=Canvas}"/>
<Binding Path="ActualHeight" RelativeSource="{RelativeSource AncestorType=Canvas}"/>
</MultiBinding>
</Setter.Value>
</Setter>
</Style>
</Polygon.Resources>
</Polygon>
</Canvas>
</Border>
</Grid>
</Window>
PS 。没有代码隐藏
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
}