C#在画布中拖放图像
我试着在谷歌上搜索如何在画布上拖放UIElements,但找不到我想要的任何东西 我有一个带窗口的C#WPF应用程序。在窗口内,我得到了一块画布,可以在其中添加图像。 我想要的是能够拖放图像,同时保持在画布的边界内。 我还希望这是在代码中,所以不是在xaml中 我在向画布添加/更新图像的函数中得到了这一点。拖放事件应替换TODOC#在画布中拖放图像,c#,wpf,canvas,drag-and-drop,draggable,C#,Wpf,Canvas,Drag And Drop,Draggable,我试着在谷歌上搜索如何在画布上拖放UIElements,但找不到我想要的任何东西 我有一个带窗口的C#WPF应用程序。在窗口内,我得到了一块画布,可以在其中添加图像。 我想要的是能够拖放图像,同时保持在画布的边界内。 我还希望这是在代码中,所以不是在xaml中 我在向画布添加/更新图像的函数中得到了这一点。拖放事件应替换TODO Image img = ImageList[i].Image; img.Name = "Image" + i; // TODO: Drag and Drop even
Image img = ImageList[i].Image;
img.Name = "Image" + i;
// TODO: Drag and Drop event for Image
// TODO: Check if Left and Top are within Canvas (minus width / height of Image)
Canvas.SetLeft(img, Left); // Default Left when adding the image = 0
Canvas.SetTop(img, Top); // Default Top when adding the image = 0
MyCanvas.Children.Add(img);
OnPropertyChanged("MyCanvas");
PS:虽然这是为了以后,如果有人有代码一次拖放多个图像作为额外的奖励,我将不胜感激
提前感谢您的帮助。我做了一个项目,它使用了您的代码块,并在画布上拖放,查看它是否有任何差异,但我没有时间检查
private void pinCanvas_PreviewMouseLeftButtonDown_1(object sender, MouseButtonEventArgs e)
{
// Point pt = e.GetPosition(pinCanvas);
// Curosor.Text = String.Format("You are at ({0}in, {1}in) in window coordinates", (pt.X / (96 / 72)) * 1/72, (pt.Y / (96 / 72)) * 1/72);
}
bool captured = false;
double x_shape, x_canvas, y_shape, y_canvas;
UIElement source = null;
string elementName;
double elementHeight, elementWidth;
private void pinCanvas_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
setCanvasSize();
source = (UIElement)sender;
elementName = ((Label)source).Name;
switch (elementName)
{
case "pinTextBox" :
elementHeight = pinActualHeight;
elementWidth = pinActualWidth;
break;
case "serialTextBox" :
elementHeight = serialActualHeight;
elementWidth = serialActualWidth;
break;
case "batchTextBox" :
elementHeight = batchActualHeight;
elementWidth = batchActualWidth;
break;
}
Mouse.Capture(source);
captured = true;
x_shape = Canvas.GetLeft(source);
x_canvas = e.GetPosition(Maincanvas).X;
y_shape = Canvas.GetTop(source);
y_canvas = e.GetPosition(Maincanvas).Y;
}
private void pinCanvas_MouseMove(object sender, MouseEventArgs e)
{
if (captured)
{
double x = e.GetPosition(Maincanvas).X;
double y = e.GetPosition(Maincanvas).Y;
var xCond = Math.Round(appActivities.DIP2Inch(x_shape), 4).ToString();
var yCond = Math.Round(appActivities.DIP2Inch(y_shape), 4).ToString();
var name = ((Label)source).Name;
x_shape += x - x_canvas;
// if ((x_shape < Maincanvas.ActualWidth - elementWidth) && x_shape > 0)
// {
Canvas.SetLeft(source, x_shape);
switch (name)
{
case "pinTextBox" :
pinOffsetLeft.Text = xCond;
break;
case "serialTextBox" :
serialOffsetLeft.Text = xCond;
break;
case "batchTextBox" :
batchOffsetLeft.Text = xCond;
break;
}
// }
x_canvas = x;
y_shape += y - y_canvas;
// if (y_shape < Maincanvas.ActualHeight - elementHeight && y_shape > 0)
// {
Canvas.SetTop(source, y_shape);
switch (name)
{
case "pinTextBox":
pinOffsetTop.Text = yCond;
break;
case "serialTextBox":
serialOffsetTop.Text = yCond;
break;
case "batchTextBox":
batchOffsetTop.Text = yCond;
break;
}
// }
y_canvas = y;
}
}
private void pinCanvas_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
Mouse.Capture(null);
captured = false;
// MessageBox.Show((Canvas.GetTop(source)).ToString());
/* if (Canvas.GetTop(source) < 0)
{
Canvas.SetTop(source, 0);
}
if (Canvas.GetLeft(source) < 0)
{
Canvas.SetLeft(source, 0);
}
if (Canvas.GetLeft(source) > Maincanvas.ActualWidth - elementWidth)
{
// MessageBox.Show("Left Too Much " + (Canvas.GetLeft(source) * 1/96).ToString());
Canvas.SetLeft(source, Maincanvas.ActualWidth - elementWidth);
}
if (Canvas.GetTop(source) > Maincanvas.ActualHeight - elementHeight)
{
Canvas.SetTop(source, Maincanvas.ActualHeight - elementHeight);
} */
oneElemntTorched = true;
//MessageBox.Show(this.pinTextBox.ActualHeight.ToString() + ", " + this.pinTextBox.ActualWidth.ToString());
}
private void pinCanvas\u PreviewMouseLeftButtonDown\u 1(对象发送器,鼠标按钮ventargs e)
{
//点pt=e.GetPosition(pinCanvas);
//Curosor.Text=String.Format(“您在窗口坐标中的({0}英寸,{1}英寸),(pt.X/(96/72))*1/72,(pt.Y/(96/72))*1/72);
}
bool=false;
双x_形状,x_画布,y_形状,y_画布;
UIElement源=空;
字符串元素名;
双元素高度、元素宽度;
私有void pinCanvas_MouseLeftButtonDown(对象发送器,MouseButtonEventArgs e)
{
setCanvasSize();
source=(UIElement)发送方;
elementName=((标签)源).Name;
开关(elementName)
{
案例“pinTextBox”:
elementHeight=销实际高度;
elementWidth=pinActualWidth;
打破
案例“serialTextBox”:
elementHeight=串行实际高度;
elementWidth=串行实际宽度;
打破
案例“batchTextBox”:
元素高度=批次实际高度;
elementWidth=批次实际宽度;
打破
}
鼠标捕捉(来源);
捕获=真;
x_shape=Canvas.GetLeft(源代码);
x_canvas=e.GetPosition(Maincanvas).x;
y_shape=Canvas.GetTop(源代码);
y_canvas=e.GetPosition(Maincanvas).y;
}
私有void pinCanvas_MouseMove(对象发送器,MouseEventArgs e)
{
如果(捕获)
{
双x=e.GetPosition(主画布).x;
双y=e.GetPosition(主画布).y;
var xCond=Math.Round(appActivities.DIP2Inch(x_形状),4).ToString();
var yCond=Math.Round(appActivities.DIP2Inch(y_形),4).ToString();
变量名称=((标签)源).name;
x_形状+=x-x_画布;
//if((x_形状0)
// {
Canvas.SetLeft(源,x_形状);
交换机(名称)
{
案例“pinTextBox”:
pinOffsetLeft.Text=xCond;
打破
案例“serialTextBox”:
serialOffsetLeft.Text=xCond;
打破
案例“batchTextBox”:
batchOffsetLeft.Text=xCond;
打破
}
// }
x_=x;
y_形状+=y-y_画布;
//if(y_形状0)
// {
Canvas.SetTop(源,y_形状);
交换机(名称)
{
案例“pinTextBox”:
pinOffsetTop.Text=yCond;
打破
案例“serialTextBox”:
serialOffsetTop.Text=yCond;
打破
案例“batchTextBox”:
batchOffsetTop.Text=yCond;
打破
}
// }
y_=y;
}
}
私有void pinCanvas_MouseLeftButtonUp(对象发送器,MouseButtonEventArgs e)
{
鼠标捕捉(空);
捕获=假;
//Show((Canvas.GetTop(source)).ToString());
/*if(Canvas.GetTop(源)<0)
{
Canvas.SetTop(源,0);
}
if(Canvas.GetLeft(源)<0)
{
Canvas.SetLeft(源,0);
}
if(Canvas.GetLeft(source)>maincavas.ActualWidth-elementWidth)
{
//Show(“左过多”+(Canvas.GetLeft(source)*1/96.ToString());
SetLeft(源代码,maincavas.ActualWidth-elementWidth);
}
if(Canvas.GetTop(source)>maincavas.ActualHeight-elementHeight)
{
Canvas.SetTop(源,maincavas.ActualHeight-elementHeight);
} */
oneElemntTorched=真;
//Show(this.pinTextBox.ActualHeight.ToString()+”,“+this.pinTextBox.ActualWidth.ToString());
}
使用以下代码修复了我下面的问题:
img.AllowDrop = true;
img.PreviewMouseLeftButtonDown += this.MouseLeftButtonDown;
img.PreviewMouseMove += this.MouseMove;
img.PreviewMouseLeftButtonUp += this.PreviewMouseLeftButtonUp;
private object movingObject;
private double firstXPos, firstYPos;
private void MouseLeftButtonDown(object sender, MouseButtonEventArgs e) {
// In this event, we get the current mouse position on the control to use it in the MouseMove event.
Image img = sender as Image;
Canvas canvas = img.Parent as Canvas;
firstXPos = e.GetPosition(img).X;
firstYPos = e.GetPosition(img).Y;
movingObject = sender;
// Put the image currently being dragged on top of the others
int top = Canvas.GetZIndex(img);
foreach (Image child in canvas.Children)
if (top < Canvas.GetZIndex(child))
top = Canvas.GetZIndex(child);
Canvas.SetZIndex(img, top + 1);
}
private void PreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e) {
Image img = sender as Image;
Canvas canvas = img.Parent as Canvas;
movingObject = null;
// Put the image currently being dragged on top of the others
int top = Canvas.GetZIndex(img);
foreach (Image child in canvas.Children)
if (top > Canvas.GetZIndex(child))
top = Canvas.GetZIndex(child);
Canvas.SetZIndex(img, top + 1);
}
private void MouseMove(object sender, MouseEventArgs e) {
if (e.LeftButton == MouseButtonState.Pressed && sender == movingObject) {
Image img = sender as Image;
Canvas canvas = img.Parent as Canvas;
double newLeft = e.GetPosition(canvas).X - firstXPos - canvas.Margin.Left;
// newLeft inside canvas right-border?
if (newLeft > canvas.Margin.Left + canvas.ActualWidth - img.ActualWidth)
newLeft = canvas.Margin.Left + canvas.ActualWidth - img.ActualWidth;
// newLeft inside canvas left-border?
else if (newLeft < canvas.Margin.Left)
newLeft = canvas.Margin.Left;
img.SetValue(Canvas.LeftProperty, newLeft);
double newTop = e.GetPosition(canvas).Y - firstYPos - canvas.Margin.Top;
// newTop inside canvas bottom-border?
if (newTop > canvas.Margin.Top + canvas.ActualHeight - img.ActualHeight)
newTop = canvas.Margin.Top + canvas.ActualHeight - img.ActualHeight;
// newTop inside canvas top-border?
else if (newTop < canvas.Margin.Top)
newTop = canvas.Margin.Top;
img.SetValue(Canvas.TopProperty, newTop);
}
}
img.AllowDrop=true;
img.PreviewMouseLeftButtonDown+=this.MouseLeftButtonDown;
img.PreviewMouseMove+=this.MouseMove;
img.PreviewMouseLeftButtonUp+=此.PreviewMouseLeftButtonUp;
私有对象移动对象;
私人双FirstXPO、FirstYPO;
私有void MouseLeftButtonDown(对象发送器,MouseButtonEventArgs e){
//在这个事件中,我们得到当前的鼠标po