This is my first time posting, so be easy on me...
There are definitely posts that show how to connect lines to blocks, but this one is slightly different. The grids are placed on the canvas dynamically. I want a line to connect the grid from where the button is pressed to the new grid that's placed on the canvas. However the below code doesn't work. I've struggled with this one for a very long time.
Solely by accident I discovered a Messagebox thrown in the button event handler will allow it to work. I figured this was from threads running at different times, but after messing with task.delay/thread.sleep/async/await I can't find the solution.
I'm using custom classes because this is a stripped down version of the larger program, I wanted to have similar functionality in my example to reflect possible errors but leave out the unnecessary pieces.
I'm using this as a last resort, thank you in advance for any help you can provide. First the CS code
using System;
using System.Collections.Generic;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
namespace WpfApplication1
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private void Button_Click(object sender, RoutedEventArgs e)
{
Grid1 g = myCanvas.CreateGrid();
ContentControl1 cc = myCanvas.CreateCC();
Button1 b = myCanvas.CreateButton1();
Grid1.SetColumn(cc, 0);
Grid1.SetRow(cc, 0);
Grid1.SetColumn(b, 1);
Grid1.SetRow(b, 1);
g.Children.Add(cc);
g.Children.Add(b);
Canvas1.SetLeft(g, 500);
Canvas1.SetTop(g, 5);
myCanvas.Children.Add(g);
}
}
public class Button1 : Button
{
protected override void OnClick()
{
Grid1 old_g = (Grid1)VisualTreeHelper.GetParent(this as DependencyObject);
Canvas1 cnv = (Canvas1)VisualTreeHelper.GetParent(old_g as DependencyObject);
Grid1 g = cnv.CreateGrid();
ContentControl1 cc = cnv.CreateCC();
Button1 b = cnv.CreateButton1();
Grid1.SetColumn(cc, 0);
Grid1.SetRow(cc, 0);
Grid1.SetColumn(b, 1);
Grid1.SetRow(b, 1);
g.Children.Add(cc);
g.Children.Add(b);
Canvas1.SetLeft(g, 500);
Canvas1.SetTop(g, cnv.Children.Count * 120);
cnv.Children.Add(g);
cnv.ConnectGrids(old_g, g);
}
}
public class Canvas1 : Canvas
{
public Grid1 CreateGrid()
{
Grid1 g = new Grid1() { Width = 100, Height = 20, Background = Brushes.White };
g.HorizontalAlignment = HorizontalAlignment.Center;
g.VerticalAlignment = VerticalAlignment.Center;
g.ShowGridLines = false;
ColumnDefinition colDef1 = new ColumnDefinition();
ColumnDefinition colDef2 = new ColumnDefinition() { Width = new GridLength(20) };
g.ColumnDefinitions.Add(colDef1);
g.ColumnDefinitions.Add(colDef2);
RowDefinition rowDef1 = new RowDefinition();
g.RowDefinitions.Add(rowDef1);
return g;
}
public ContentControl1 CreateCC()
{
ContentControl1 cc = new ContentControl1()
{
VerticalContentAlignment = VerticalAlignment.Stretch,
HorizontalContentAlignment = HorizontalAlignment.Stretch,
BorderBrush = Brushes.BlueViolet,
};
return cc;
}
public Button1 CreateButton1()
{
Button1 b = new Button1()
{
VerticalContentAlignment = VerticalAlignment.Stretch,
HorizontalContentAlignment = HorizontalAlignment.Stretch,
BorderBrush = Brushes.Red
};
return b;
}
public void ConnectGrids(Grid1 g1, Grid1 g2)
{
Canvas1 cnv = (Canvas1)VisualTreeHelper.GetParent(g1 as DependencyObject);
Transform transform1 = (Transform)g1.TransformToVisual(cnv as Visual);
Transform transform2 = (Transform)g2.TransformToVisual(cnv as Visual);
Point StartPoint1 = transform1.Transform(new Point(g1.Width, g1.Height / 2.0));
Point EndPoint1 = transform2.Transform(new Point(g2.Width, g2.Height / 2.0));
var lineGeometry = new LineGeometry()
{
StartPoint = StartPoint1,
EndPoint = EndPoint1
};
var path = new Path()
{
Data = lineGeometry,
Stroke = new SolidColorBrush(Colors.Black),
};
cnv.Children.Add(path);
}
}
public class ContentControl1 : ContentControl
{
}
public class Grid1 : Grid
{
}
}
then the xaml:
<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local ="clr-namespace:WpfApplication1"
Title="MainWindow" Height="1000" Width="1000">
<DockPanel>
<Button DockPanel.Dock="Top" Width="100" Height="20" Content="Start" Click="Button_Click"/>
<ScrollViewer HorizontalScrollBarVisibility="Visible" Width="901" x:Name="_scrollViewer" Margin="0,5,0,25">
<local:Canvas1 Background="Gray" Height="1000" Width="1000" x:Name="myCanvas"/>
</ScrollViewer>
</DockPanel>
</Window>
How can I successfully connect the grid with the path?
