Tiling Windows Offset using Infragistics Dialog Window

Question

I am using the Infragistics XamDialogWindow to approximate an MDI window in WPF.

Basically I have a user control that I assign to the content of the window and then add the XamDialogWindow as a child of a Grid.

I then have two buttons which display the windows as either "Tile" or "Cascade".

The cascade works really well but I am having problems with the Tile method.

I get the available width and height using the "ActualWidth" and "ActualHeight" properties of the container.

I then calculate the number of rows and columns needed.

Next I iterate through the columns and I calculate how many rows there are in a column, (this means that if there are an odd number of windows such as 5 I will have two rows in column 0 and 3 in column 1).

The width of each window is worked out as "AvailableWidth / numColumns"

The height of each window is worked out as "AvailableHeight / WindowsForThisColumn"

I then iterate through the rows and calculate the top left coordinate of the window we are positioning as follows:

left = columnIndex * width

top = rowIndex * height

The Left, Top, Width and Height properties of the window are then set.

PROBLEM

The Left, Top, Width and Height properties seem to be calculated correctly so for example

• AvailableWidth = 1000;
• AvailableHeight = 1000;
• Window1 = 0, 0, 500, 500
• Window2 = 0, 500, 500, 500
• Window3 = 500, 0,500, 500
• Window4 = 500, 500, 500, 500

This should give a nice grid of 4 windows with no margins filling all available space, however this is not the result.

The windows seem to be offset when displayed (see image below).

If I look at the Left, Top, Width and Height properties they all appear to be correct.

The weird thing is, if I click "Tile" a second time they will all appear correctly.

If I move a window after clicking tile the second time, they will appear correctly.

I have tried using a Canvas and setting the Canvas.Left and Top properties, A grid, stackpanel and wrappanel with the same results every time.

Can anyone help me? I think it may be a problem with how WPF measures sizes and locations at Render Time

 var childrenToArrange = Children.Where(a => a.WindowState != Infragistics.Controls.Interactions.WindowState.Minimized).ToList();

        var availableWidth = Panel.ActualWidth;
        var availableHeight = Panel.ActualHeight;

        if (Layout == MDILayout.TILE)
        {
            //get the number of rows and columns
            int rows = (int)Math.Sqrt(childrenToArrange.Count);
            int columns = childrenToArrange.Count / rows;

            var index = 0;
            var width = availableWidth / columns;

            //iterate through the columns
            for (int x = 0; x < columns; x++)
            {
                //get the number of windows for this column
                var windowsForThisColumn = rows;
                if (childrenToArrange.Count % columns > (columns - x - 1))
                    windowsForThisColumn++;

                var height = availableHeight / windowsForThisColumn;

                //iterate through the rows
                for (int y = 0; y < windowsForThisColumn; y++)
                {
                    //get the X and Y coordinates
                    var left = x * width;
                    var top = y * height;

                    //get the window
                    var mdiChild = childrenToArrange[index] as XamDialogWindow;

                    mdiChild.Margin = new Thickness(0);
                    mdiChild.Left = left;
                    mdiChild.Top = top;
                    mdiChild.Width = width;
                    mdiChild.Height = height;
                    index++;
                }
            }
        }

Answer 1

I've reproduced the issue with your snippet. Please click the following hyperlink to the following forum post at Infragistics for further instructions.

• Michael DiFilippo