我正在 WPF 中开发一个桌面应用程序，其中包含不同类型的形状（如圆、半径圆、直径圆）。现在我需要根据需要调整形状的大小，所以我使用.Net adorner了它提供了拖动和调整形状大小的灵活性。确切的问题是我想同时调整两个元素的大小（即*当我调整圆的大小时，半径 Line 也应该根据半径起点和终点调整大小）。
注意我没有尝试任何东西（我还没有进行任何开发，所以我没有编码）。
更新了您的代码的试用版。这是一个直径圆所以当我拖动它时它只会拖动椭圆
public class SimpleCircleAdorner : Adorner
{
// Be sure to call the base class constructor.
public SimpleCircleAdorner(UIElement adornedElement, Panel ownerPanel)
: base(adornedElement)
{
_ownerPanel = ownerPanel;
}
protected override void OnMouseEnter(MouseEventArgs e)
{
Point point = Mouse.GetPosition(AdornedElement);
_currentPosition = getMousePosition(point);
switch (_currentPosition)
{
case MousePosition.BR:
case MousePosition.TL:
Cursor = Cursors.SizeNWSE;
break;
case MousePosition.BL:
case MousePosition.TR:
Cursor = Cursors.SizeNESW;
break;
}
}
protected override void OnMouseLeave(MouseEventArgs e)
{
AdornerLayer adornerLayer = AdornerLayer.GetAdornerLayer(AdornedElement);
if (adornerLayer != null)
{
Adorner[] adorners = adornerLayer.GetAdorners(AdornedElement);
if (adorners != null)
{
foreach (Adorner adorner in adorners)
{
adornerLayer.Remove(adorner);
}
}
}
}
MousePosition _currentPosition;
Panel _ownerPanel;
bool _isDraging = false;
Point _startPosition;
protected override void OnPreviewMouseLeftButtonDown(MouseButtonEventArgs e)
{
if (Mouse.Capture(this))
{
_isDraging = true;
_startPosition = Mouse.GetPosition(_ownerPanel);
}
}
protected override void OnPreviewMouseMove(MouseEventArgs e)
{
if (_isDraging)
{
Point newPosition = Mouse.GetPosition(_ownerPanel);
double diffX = (newPosition.X - _startPosition.X);
double diffY = (newPosition.Y - _startPosition.Y);
// we should decide whether to change Width and Height or to change Canvas.Left and Canvas.Right
if (Math.Abs(diffX) >= 1 || Math.Abs(diffY) >= 1)
{
switch (_currentPosition)
{
case MousePosition.TL:
case MousePosition.BL:
foreach (FrameworkElement ui in _ownerPanel.Children)
{
if (ui.GetType() == typeof(Ellipse) || ui.GetType() == typeof(Line))
{
Canvas.SetLeft(ui, Math.Max(0, Canvas.GetLeft(ui) + diffX));
ui.Width = Math.Max(0, ui.Width - diffX);
}
}
_ownerPanel.InvalidateArrange();
break;
case MousePosition.BR:
case MousePosition.TR:
foreach (FrameworkElement ui in _ownerPanel.Children)
{
if (ui.GetType() == typeof(Ellipse) || ui.GetType() == typeof(Line))
{
ui.Width = Math.Max(0, ui.Width + diffX);
}
}
break;
}
switch (_currentPosition)
{
case MousePosition.TL:
case MousePosition.TR:
foreach (FrameworkElement ui in _ownerPanel.Children)
{
if (ui.GetType() == typeof(Ellipse) || ui.GetType() == typeof(Line))
{
Canvas.SetTop(ui, Math.Max(0, Canvas.GetTop(ui) + diffY));
}
}
foreach (FrameworkElement ui in _ownerPanel.Children)
{
if (ui.GetType() == typeof(Ellipse) || ui.GetType() == typeof(Line))
{
ui.Height = Math.Max(0, ui.Height - diffY);
}
}
break;
case MousePosition.BL:
case MousePosition.BR:
foreach (FrameworkElement ui in _ownerPanel.Children)
{
if (ui.GetType() == typeof(Ellipse) || ui.GetType() == typeof(Line))
{
ui.Height = Math.Max(0, ui.Height + diffY);
}
}
break;
}
}
_startPosition = newPosition;
}
}
protected override void OnPreviewMouseLeftButtonUp(MouseButtonEventArgs e)
{
}
protected override void OnPreviewMouseRightButtonUp(MouseButtonEventArgs e)
{
if (_isDraging)
{
Mouse.Capture(null);
_isDraging = false;
}
}
MousePosition getMousePosition(Point point) // point relative to element
{
double h2 = ActualHeight / 2;
double w2 = ActualWidth / 2;
if (point.X < w2 && point.Y < h2)
return MousePosition.TL;
else if (point.X > w2 && point.Y > h2)
return MousePosition.BR;
else if (point.X > w2 && point.Y < h2)
return MousePosition.TR;
else
return MousePosition.BL;
}
enum MousePosition
{
TL,
TR,
BL,
BR
}
double _renderRadius = 5.0;
protected override void OnRender(DrawingContext drawingContext)
{
Rect adornedElementRect = new Rect(this.AdornedElement.DesiredSize);
SolidColorBrush renderBrush = new SolidColorBrush(Colors.Black);
renderBrush.Opacity = 0.3;
Pen renderPen = new Pen(new SolidColorBrush(Colors.Black), 1.5);
drawingContext.DrawEllipse(renderBrush, renderPen, adornedElementRect.TopLeft, _renderRadius, _renderRadius);
drawingContext.DrawEllipse(renderBrush, renderPen, adornedElementRect.TopRight, _renderRadius, _renderRadius);
drawingContext.DrawEllipse(renderBrush, renderPen, adornedElementRect.BottomLeft, _renderRadius, _renderRadius);
drawingContext.DrawEllipse(renderBrush, renderPen, adornedElementRect.BottomRight, _renderRadius, _renderRadius);
}
}
