I am working on extending the Microsoft resize Adorner example and need to be able to reposition the element after say the bottom left drag handle has been dragged.
So if I have a textbox of say 150 wide, 35 high postitioned on my form, and the bottom left drag handle changes the width to 200 wide, the right hand of the text box remains unchanged but the left hand edge moves to the left.
So I need to know the top left coordinates of the UIElement. I have tried Canvas.GetLeft and Canvas.GetTop but they return NaN which is confusing.
I just tried VisualTreeHelper.GetOffset which does return an offset but when you try and use it in the arrange method of the element it disappears, presumably as the values in the offset are too high.
In the days before Wpf the coordinate system was quite simple, wpf has overcomplicated things I think.
And if someone just wants the control's screen coordinates:
Point targetLoc = targetCtrl.PointToScreen(new Point(0, 0));
(this doesn't match the thread's description, but it does match the title. Figured it might help people coming in off search results)
You can transform coordinates of the UIElement to its parent. In your case it's a form. Here is an example of a method that returns coordinates of a visual:
private Point GetPosition(Visual element) {
var positionTransform = element.TransformToAncestor(MyForm);
var areaPosition = positionTransform.Transform(new Point(0, 0));
return areaPosition;
}
Related
I have this form that works perfectly fine on resolution 1920 x 1080 (mainly cause I made it using that resolution). I read information about controls from a database (labels and textboxs). This information tells me where to place the controls. Like I said, on 1920 x 1080 everything is placed correctly. When I go down resolutions the form is now bigger than the resolution so I added scroll bars. Issue is that the controls are being placed as if the form that is visable on the screen is all that there is. So if I were to place a textbox at location (4, 90) on the form on lower resolution it might place it at (100,90). Y coord is fine, X coord is not.
Although TableLayoutPanels looks very nice in this case it would be a complete hassle and a waste of time to basically completely redo what I have done already. If I were to have started fresh I probably would have used TableLayoutPanels. Instead what I did was, since the Form was bigger than the resolution, I turned my forms AutoScroll to true (which I said in the question). I then set the AutoScrollPosition to (0,0) on form_shown which makes the horizontal one go to the left and the vertical one to the top using...
this.AutoScrollPosition = new Point(0,0);
Since the controls information is based off of where they are on the screen I just force the form's top left to be located in the top left of the screen and not off. I also had to have an override for the ScrollToControl. Every time a control was placed it would reset back to the center and would mess the placement up. So I added this...
protected override Point ScrollToControl(Control activeControl)
{
return this.AutoScrollPosition;
}
I have a GridView in a windows store project, that contains some big squares, and inside those i have a list of user images, when i tap on of those images a flyout appears on the right showing some information like this.
the problem is that my gridview extends to the edges of the screen and beyond, and when that does i get this situation, i press the user with the red border near the edge of the screen and flyout appears on left.
My flyout placement is set to Right, and im guessing since the element i press is near the edge it follows the Fall back order with according to this is Right > Left > Top > Bottom.
What i would like to know is how to detect this happens, so i can adjust my flyout position, or another viable alternative :)
After searching through properties and Dependency properties on Flyout and FlyoutBase, I haven't found a way to simply get the actual placement of the Flyout (which is unfortunate because I think that can be important, as we see in your case). Perhaps you can try what was proposed here by implementing a method that compares the desired size of the Flyout with the available space.
You can subscribe to FlyOut.Opened event and compare absolute coordinates of the flyout and the element you're showing it at. Here is an example for top/bottom flyout placement (easily extendable to check for left/right as well):
private void FlyOut_Opened(object sender, object e)
{
GeneralTransform flyOutTransform =
flyOut.Content.TransformToVisual(Window.Current.Content);
Point flyOutPosition =
flyOut.TransformPoint(new Point(0, 0));
GeneralTransform showAtElementTransform =
showAtElementTransform.TransformToVisual(Window.Current.Content);
Point showAtElementPosition =
showAtElementPosition.TransformPoint(new Point(0, 0));
if(flyOutPosition.Y < showAtElementPosition.Y)
{
// top
}
else
{
// bottom
}
}
I have a Windows Forms application with a control. The control consists of a chart panel with a canvas on which I paint. What I would like to do is to programmatically mouse drag the panel so that I have a specific distance between the right edge of the canvas and the last item painted on the canvas. I have tried two approaches. The both work in the sense that the panel is dragged as desired BUT I cannot seem to be able to get the precision of movement I desire. I coded a mouse simulator and have tried two approaches.
Approach 1:
if(this.ChartControl.ChartPanel.CanFocus)
{
// ... Focus the chart panel to be adjusted.
this.ChartControl.ChartPanel.Focus();
// ... Move cursor to lastBarScreenCoordinates on the chart panel to be adjusted.
Cursor.Position = new Point(lastBarScreenCoordinates.X, lastBarScreenCoordinates.Y);
MouseSimulator.SetMouseDragThresholds();
// ... Move chart panel to required position.
MouseSimulator.LeftMouseButtonDown(lastBarScreenCoordinates.X, lastBarScreenCoordinates.Y);
MouseSimulator.MouseMove(lastBarScreenCoordinates.X-positionShift,
lastBarScreenCoordinates.Y);
MouseSimulator.LeftMouseButtonUp(lastBarScreenCoordinates.X-positionShift,
lastBarScreenCoordinates.Y);
MouseSimulator.ResetMouseDragThresholds(_cx_default, _cy_default);
// ... Redraw the chart panel.
this.ChartControl.ChartPanel.Refresh();
// ... Reset cursor to its starting position.
Cursor.Position = new Point(startingCursorX, startingCursorY);
}
Approach 2:
if(this.ChartControl.ChartPanel.CanFocus)
{
// ... Focus the chart panel to be adjusted.
this.ChartControl.ChartPanel.Focus();
// ... Move cursor to lastBarScreenCoordinates on the chart panel to be adjusted.
Cursor.Position = new Point(lastBarScreenCoordinates.X, lastBarScreenCoordinates.Y);
MouseSimulator.SetMouseDragThresholds();
// ... Move chart panel to required position.
MouseSimulator.LeftMouseButtonDown(lastBarScreenCoordinates.X, lastBarScreenCoordinates.Y);
Cursor.Position = new Point(lastBarScreenCoordinates.X-positionShift,
lastBarScreenCoordinates.Y);
WindowsCommunication.SendMessage(this.ChartControl.Handle, 0x200, IntPtr.Zero,IntPtr.Zero);
MouseSimulator.LeftMouseButtonUp(lastBarScreenCoordinates.X-positionShift,
lastBarScreenCoordinates.Y);
MouseSimulator.ResetMouseDragThresholds(_cx_default, _cy_default);
// ... Redraw the chart panel.
this.ChartControl.ChartPanel.Refresh();
// ... Reset cursor to its starting position.
Cursor.Position = new Point(startingCursorX, startingCursorY);
}
I am using SendInput for simulating mouse clicks. Here is sample left mouse button down code ...
public static void LeftMouseButtonDown(int x, int y)
{
INPUT mouseInput = new INPUT();
mouseInput.type = SendInputEventType.InputMouse;
mouseInput.mkhi.mi.dx = CalculateAbsoluteCoordinateX(x);
mouseInput.mkhi.mi.dy = CalculateAbsoluteCoordinateY(y);
mouseInput.mkhi.mi.mouseData = 0;
mouseInput.mkhi.mi.time = 0;
mouseInput.mkhi.mi.dwFlags = MouseEventFlags.MOUSEEVENTF_LEFTDOWN;
SendInput(1, ref mouseInput, Marshal.SizeOf(new INPUT()));
}
And I calculate normalized absolute coordinates for the mouse as follows ...
private static int CalculateAbsoluteCoordinateX(int x)
{
return ((x * 65536) + GetSystemMetrics(SystemMetric.SM_CXSCREEN) - 1) /
GetSystemMetrics(SystemMetric.SM_CXSCREEN);
}
So here are the precision issues. If I use Approach 1 (mouse move), the measured distance between the last item painted and the right edge of the canvas is different from what I set in positionShift and the cursor position difference does not equal positionShift. I initially thought it was due to pointer ballistics issues so I tried using Approach 2. Approach 2 does give me precision in pointer positioning but I am still having difficulty in that the panel moves but the distance between the last bar painted and the right edge of the canvas does not equal the positionShift amount as it should. It always seems to be off. I have been working on this for a long time now and am at my wits end. I am not sure what is going on here. How to improve the precision in my canvas drag by simulated mouse drag?
Well what you can do is this, First of all I believe the SendInput API allows for an AbsoluteValue flag so there is no need to calculate those values which may be the issue but most likely not.
Although I am curious as to why you are using a Mouse Drag opperation for this. It seems like all you want to do is reposition the canvas on every draw by some specified amount. if this is the case why not just set it explicitly on the canvas itself. Also it is unclear if you are using pure WinForms or WPF. The unclear bit being Canvas which I am fairly certain is only usable with WPF enabled windows.
That being said
WPF fix,
Depending on the Object containing the canvas just set its margin appropriately for the situation, since I do not know the data you are working with I cant say much about that. But this is a relatively simple idea so let me know if that works, it should give you, at least close too, a pixel perfect alignment.
WinForms,
Just do the above for the "Canvas" object you were talking about, or use absolute coordinates of the object to move it around.
If you could supply a sample of what you were working on looked like roughly maybe we could have a better idea of what you mean.
Another problem in my WPF questions series :)
I'm creating custom Decorator that will be used to decorate Panels (or it can be Behavior, no difference).
That Decorator deals with elements that are in that Panel (Children property of the Panel). It attaches some RenderTransforms to those elements. Now I need a position of some element ('child' of the Panel) relative to the Panel itself. In other words I need a position if some child element in the Panels coordinate space. in just another words I want the offset that was specified by the ArrangeOverride method of the Panel when calling Arrange method on Children.
That seem to be easy. But I cannot find the way to always get right coordinates.
This code
VisualTreeHelper.GetOffset(child)
does not work when the panel is inside ScrollView - it takes topmost, leftmost visible corner of the Panel as an origin of coordinate space - not the real topmost and leftmost corner of the Panel.
The code
Point position = child.TransformToAncestor(panel).Transform(new Point(0,0));
will not work when some render transforms are already active on the child element of the Panel. It will return the position of transformed image(by the render transfrom) of child element. The render position.
The same problem is with this aproach:
Point panelPosition = panel.PointToScreen(new Point(0, 0));
Point childPosition = child.PointToScreen(new Point(0, 0));
Point position = new Point(childPosition.X - panelPosition.X, childsPosition.Y - panelPosition.Y);
So this i what I have tryied but it did not work. I have 2 similar questions on this topic that were tying to simplify the problem, so I got some of suggestions above. Now I introduced the problem in its full complexity, I hope to get the right advice.
If something is unclear please leave the comment.
Thank you
You can "undo" the RenderTransform before calling TransformToAncestor:
Point origin = child.RenderTransform.Inverse.Transform(new Point(0, 0));
Point position = child.TransformToAncestor(listBox).Transform(origin);
I have a control whose parent is a ScrollableControl. How do I find the part of the control that's actually visible to the user? Both are rectangular - there's no funny business with Regions.
I think the GetVisibleRectangle method I wrote below is what you were requesting. Successive runs of this with scrolling yielded the following output as the control was scrolled:
{X=0,Y=0,Width=0,Height=0} - button4 was scrolled out of view. Note that the value here is Rectangle.Empty.
{X=211,Y=36,Width=25,Height=13} - button4 was scrolled so the upper left corner was visible
{X=161,Y=36,Width=75,Height=13} - button4 was scrolled so the top half and entire width was visible
{X=161,Y=26,Width=75,Height=23} - button4 was scrolled to be entirely visible
Note how in addition to the Width and Height changes that the X,Y also changed with scrolling.
Source:
private void button1_Click(object sender, EventArgs e)
{
Rectangle r = GetVisibleRectangle(this.panel1, button4);
System.Diagnostics.Trace.WriteLine(r.ToString());
}
public static Rectangle GetVisibleRectangle(ScrollableControl sc, Control child)
{
Rectangle work = child.Bounds;
work.Intersect(sc.ClientRectangle);
return work;
}
AutoScrollPosition represents the location of the scrollable control's display rectangle. The X and Y coordinate values retrieved are negative if the control has scrolled away from its starting position (0,0). When you set this property, you must always assign positive X and Y values to set the scroll position relative to the starting position. For example, if you have a horizontal scroll bar and you set x and y to 200, you move the scroll 200 pixels to the right; if you then set x and y to 100, the scroll appears to jump the left by 100 pixels, because you are setting it 100 pixels away from the starting position. In the first case, AutoScrollPosition returns {-200, 0}; in the second case, it returns {-100,0}.
Source: MSDN: ScrollableControl.AutoScrollPosition Property
The following link might helps to resolve this problem
http://www.trace-solution.com/2012/06/how-to-get-visibleviewable-area-of-user.html .