If I have the following code and want to align button control to horizontally center of the Form.
let myForm:Form = new Form()
myForm.Text <- "myForm"
myForm.Height <- 500
myForm.Width <- 500
let button:Button = new Button()
button.Text <- "Click"
myForm.Controls.Add(button)
button.Location <- Point(200, 20)
// Using this code to align this control to center
Please suggest me a good way of horizontally center aligning a control. The above will not work if Form is maximized. And please suggest me to improve the code if there are any other good practices.
Thanks
This is how I'd do it in C#. Maybe it can help you.
Resize += new EventHandler(Form1_Resize);
And:
void Form1_Resize(object sender, EventArgs e)
{
button1.Location = new Point(this.ClientSize.Width / 2 - button1.Width / 2, button1.Location.Y);
}
Translating #ispiro's answer to F# - if you want to recenter every time the form is resized
Form1.Resize.Add (fun _ -> button1.Location <- new Point(this.ClientSize.Width / 2 - button1.Width / 2, button1.Location.Y))
If this is only happending in the constructor, you can just do
button.Location <- Point(myForm.Width / 2 - button.Width / 2, button.Location.Y)
Related
I am tinkering with using F# scripts and I'm just wanting to draw lines on a blank Windows Form with a simple button click. Hopefully you can see what I'm trying to do here:
open System.Drawing
open System.Windows.Forms
let form = new Form(Width = 400, Height = 400, Text = "draw test")
let panel = new FlowLayoutPanel()
form.Controls.Add(panel)
let paint(e : PaintEventArgs) =
let pen = new Pen(Color.Black);
e.Graphics.DrawLine(pen, new PointF(100.0f, 100.0f), new PointF(200.0f, 200.0f))
let button = new Button()
button.Text <- "Click to draw"
button.AutoSize <- true
button.Click.Add(fun _ -> form.Paint.Add(paint)) // <- does not draw a line on click
panel.Controls.Add(button)
//form.Paint.Add(paint) <- here, if uncommented, it will draw a line when the script is run
form.Show()
If I take the form.Paint.Add(paint) uncomment it above form.Show(), then of course it will draw on the form, but I'm trying to do it with a button click. It's not exactly clear to me how to make this happen in a script like this, and I've been scouring all over for a similar example in F#. Any help would be appreciated.
If you add your Paint event handler before the form is drawn for the first time, then it will draw using that handler.
If you add it after, you need to make sure the form then redraws itself. You could for instance call Refresh or Invalidate on it.
Ex.:
button.Click.Add(fun _ -> form.Paint.Add(paint); form.Invalidate())
Originally an edit, I moved it to the answer section:
Okay, so I was confused about the difference between WPF and Winforms due to the fact that I have seen the terms used together various places... #Asik has added an answer for Winforms, but here I have slapped together a working .fsx script specifically for WPF based on several FSharp Snippets (as well as several Google searches) which can also be compiled if so desired. I'll update this as needed or requested. Also, just to point out, the whole motivation behind this is to be able to quickly test drawing graphics via FSI.
#r #"PresentationCore"
#r #"PresentationFramework"
#r #"WindowsBase"
#r #"System.Xaml"
#r #"UIAutomationTypes"
open System
open System.Windows
open System.Windows.Media
open System.Windows.Shapes
open System.Windows.Controls
let window = Window(Height = 400.0, Width = 400.0)
window.Title <- "Draw test"
let stackPanel = StackPanel()
window.Content <- stackPanel
stackPanel.Orientation <- Orientation.Vertical
let button1 = Button()
button1.Content <- "Click me to draw a blue ellipse"
stackPanel.Children.Add button1
let button2 = Button()
button2.Content <- "Click me to draw a red ellipse"
stackPanel.Children.Add button2
let clearButton = Button()
clearButton.Content <- "Click me to clear the canvas"
stackPanel.Children.Add clearButton
let canvas = Canvas()
canvas.Width <- window.Width
canvas.Height <- window.Height
stackPanel.Children.Add canvas
let buildEllipse height width fill stroke =
let ellipse = Ellipse()
ellipse.Height <- height
ellipse.Width <- width
ellipse.Fill <- fill
ellipse.Stroke <- stroke
ellipse
let ellipse1 = buildEllipse 100.0 200.0 Brushes.Aqua Brushes.Black
Canvas.SetLeft(ellipse1, canvas.Width / 10.0) //messy, will fix at some point!
Canvas.SetTop(ellipse1, canvas.Height / 10.0)
let ellipse2 = buildEllipse 200.0 100.0 Brushes.Red Brushes.DarkViolet
Canvas.SetLeft(ellipse2, canvas.Width / 4.0)
Canvas.SetTop(ellipse2, canvas.Height / 5.0)
let addEllipseToCanvas (canvas:Canvas) (ellipse:Ellipse) =
match canvas.Children with
| c when c.Contains ellipse ->
canvas.Children.Remove ellipse
canvas.Children.Add(ellipse) |> ignore //needs to be removed and readded or the canvas complains
| _ ->
canvas.Children.Add(ellipse) |> ignore
button1.Click.Add(fun _ -> addEllipseToCanvas canvas ellipse1)
button2.Click.Add(fun _ -> addEllipseToCanvas canvas ellipse2)
clearButton.Click.Add(fun _ -> canvas.Children.Clear())
#if INTERACTIVE
window.Show()
#else
[<EntryPoint; STAThread>]
let main argv =
let app = new Application()
app.Run(window)
#endif
I am trying to Printing Datagridview by making bitmap image , Its working nicely but it printing only in 1 page to print .
Here is DataGirdView Image :
Print Preview Image :
Here in print-Preview not having total rows to the last as of DataGridView row and only having 1 page
Code of Printing :
private void Btn_Print_Click(object sender, EventArgs e)
{
int height = DGV.Height;
DGV.Height = DGV.RowCount * DGV.RowTemplate.Height * 2;
bmp = new Bitmap(DGV.Width, DGV.Height);
DGV.DrawToBitmap(bmp, new Rectangle(0, 0, DGV.Width, DGV.Height));
DGV.Height = height;
printPreviewDialog1.ShowDialog();
}
private void printDocument1_PrintPage(object sender, System.Drawing.Printing.PrintPageEventArgs e)
{
e.Graphics.DrawImage(bmp, 0, 0);
}
Why not printing data in more than 1 page ? Is there any wrong in code ? Please give suggestion
Thank you .
It's not the easiest thing to print multiple pages from a DataGridView so I recommend you to use one of the existing code samples. Here's couple good ones which are easy to use and can print multiple pages:
Another DataGridView Printer
DataGridView Print/Print Preview Solution
Some more examples are available from this SO question:
Best way to print a datagridview with all rows and all columns?
I have a question regarding WPF.
I have a Canvas that serves as a visual editor! I have a few 'nodes' positioned in the Canvas using 'X' and 'Y' properties (Canvas.Left and Canvas.Top). Now, I need this Canvas to let the user Zoom (in & out) and Pan around, as he want's to.
I implemented kind of a hack to emulate that behavior. This is the Code that let's the user 'pan' around in the Canvas:
///In file MainWindow.xaml.cs
private void ZoomPanCanvas_MouseMove(object sender, MouseEventArgs e) {
if (IsMouseDown) {
///Change the Cursor to Scroll
if (mNetworkUI.Cursor != Cursors.ScrollAll)
mNetworkUI.Cursor = Cursors.ScrollAll;
var currPosition = e.GetPosition(mNetworkUI);
var diff = currPosition - MouseLastPosition;
var p = new Point(diff.X, diff.Y);
mNetworkUI.ViewModel.Network.SetTransformOffset(p);
MouseLastPosition = currPosition;
}
}
///In file NetworkViewModel.cs
public void SetTransformOffset(Point newOffset) {
for (int i = 0; i < Nodes.Count; i++) {
Nodes[i].X += newOffset.X;
Nodes[i].Y += newOffset.Y;
}
}
Where the 'Nodes' are my editor-nodes displayed in the Canvas. The Zooming (with respect to the mouse position works as follows:
///File MainWindow.xaml.cs
private void ZoomPanCanvas_MouseWheel(object sender, MouseWheelEventArgs e) {
///Determine the Scaling Factor and Scale the Rule-Editor
var factor = (e.Delta > 0) ? (1.1) : (1 / 1.1);
currrentScale = factor * currrentScale;
ScaleNetwork();
///Translate the Nodes to the desired Positions
var pos = e.GetPosition(mNetworkUI);
var transform = new ScaleTransform(factor, factor, pos.X, pos.Y);
var offSet = new Point(transform.Value.OffsetX, transform.Value.OffsetY);
mNetworkUI.ViewModel.Network.SetTransformOffset(offSet);
}
///Also in MainWindow.xaml.cs
private void ScaleNetwork() {
mNetworkUI.RenderTransform = new ScaleTransform(currrentScale, currrentScale);
mNetworkUI.Width = ZoomPanCanvas.ActualWidth / currrentScale;
mNetworkUI.Height = ZoomPanCanvas.ActualHeight / currrentScale;
}
So, in the 'panning' I calculate the difference to the last mouse position and use that vector to manipulate the nodes, not the Canvas itself.
When I zoom, I determine the new zoom, set a new RenderTransform, resize the Canvas to again fill the provided space and again re-position the nodes in the Canvas.
It works very well for now. I can 'pan & zoom' around how I want, but I realized, that with many nodes present in my 'network' (connected nodes), things get quite slow.
One reason is, that on every movement of a node some events are raised resulting in a noticable delay when panning.
How is such a thing (without fixed Canvas-size and Scrollbars) possible in a performant manner? Is there a control out there that I can use? Is this possible with the Extended WPF toolkit's ZoomBox control?
Thank you!
I've written a Viewport control for this exact functionality.
I've also packaged this up on nuget
PM > Install-Package Han.Wpf.ViewportControl
It extends a ContentControl which can contain any FrameworkElement and provides constrained zoom and pan functionality. Just make sure to add Generic.xaml to your app.xaml
<Application.Resources>
<ResourceDictionary Source="pack://application:,,,/Han.Wpf.ViewportControl;component/Themes/Generic.xaml" />
</Application.Resources>
Usage:
<Grid width="1200" height="1200">
<Button />
</Grid>
The source code for the control and theme is on my gist and can be found on my github along with a demo application that loads an image into the viewport control.
I have a WPF Image inside a Border I currently am able to click and drag to pan the image. I want to prevent users from dragging the image off the screen. Perhaps a minimum of 100 pixels should be showing at any border. That is, if a user drags the image all the way to the left, most of the image will disappear, but 100 pixels will still be hanging out toward the left boundary of the border.
Here's my current code for the MouseMove and LeftClick event:
private void img_Box_MouseMove(object sender, MouseEventArgs e)
{
if (!img_Box.IsMouseCaptured) return;
var tt = (TranslateTransform)((TransformGroup)img_Box.RenderTransform).Children.First(tr => tr is TranslateTransform);
Vector v = start - e.GetPosition(img_Border);
tt.X = origin.X - v.X;
tt.Y = origin.Y - v.Y;
}
private void img_Box_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
img_Box.CaptureMouse();
var tt = (TranslateTransform)((TransformGroup)img_Box.RenderTransform).Children.First(tr => tr is TranslateTransform);
start = e.GetPosition(img_Border);
origin = new System.Windows.Point(tt.X, tt.Y);
}
I think I should be able to put a pretty simple condition on that to achieve my desired result, but I can't figure out what the condition should be.
I want to add a number of canvas to another canvas but the following code doesn't seem to work, the application compiles but only a blank window is displayed. Ideally this would show the canvases in a diagonal line.
Here is my vb.net code:
For r As Integer = 1 To 10
X += 5
Y += 5
Dim c As Canvas = New Canvas()
Dim s As SolidColorBrush = New SolidColorBrush
s.Color = Color.FromRgb(255, 0, 0)
c.Background = s
c.Name = "cnv" + CStr(X)
c.Margin = New Thickness(X, Y, 0, 0)
cnvOverLay.Children.Add(c)
cnvOverLay.UpdateLayout()
Next
I have tried to add multiple buttons using dim b As Button = new Button() instead of creating a new canvas every time, that worked fine.
Am I missing something simple?
You cannot see the canvases be because the do not have a width and a height.