private void Rectangle_MouseDown(object sender, MouseButtonEventArgs e)
{
if (sender is Rectangle rectangle)
{
var stackPanel = VisualTreeTraverseHelper.FindParent <StackPanel>(rectangle);
if (stackPanel != null)
{
// we've got this!
}
var grid = VisualTreeTraverseHelper.FindParent <Grid>(rectangle);
if (grid != null)
{
// we've got this!
}
var lazyStackPanel = VisualTreeTraverseHelper.FindVisualParentByName(rectangle, "LazyStackPanel") as StackPanel;
if (lazyStackPanel != null)
{
// cool
}
}
}
// Control authors who want to customize the arrange pass of layout processing should
// override this method. The implementation pattern should call Arrange(Rect) on each visible child element,
// and pass the final desired size for each child element as the finalRect parameter. Parent elements should
// call Arrange(Rect) on each child, otherwise the child elements will not be rendered.
protected override Size ArrangeOverride(Size finalSize)
{
this._numberOfChildren = 0;
var listOfWidths = new List <double>();
var location = new Point();
var listView = VisualTreeTraverseHelper.FindParent <ListView>(this.TemplatedParent);
if (listView != null)
{
// get all of the desired widths in order
// to pick up the greatest width of all children
for (int i = 0; i < listView.Items.Count; i++)
{
var listViewItem = (ListViewItem)listView.ItemContainerGenerator.ContainerFromIndex(i);
if (listViewItem != null)
{
var rootStackPanel = VisualTreeTraverseHelper.FindDescendant <StackPanel>(listViewItem);
if (rootStackPanel != null)
{
foreach (var child in rootStackPanel.Children)
{
var frameworkElement = child as FrameworkElement;
if (frameworkElement != null)
{
listOfWidths.Add(frameworkElement.DesiredSize.Width);
}
}
}
}
}
// first pass won't have any desired sizes
// second pass should have.
if (listOfWidths.Count > 0)
{
double maxValue = listOfWidths.Max <double>();
// iterate through children again, but this time
// let's set our desired width to each of them
for (int i = 0; i < listView.Items.Count; i++)
{
var listViewItem = (ListViewItem)listView.ItemContainerGenerator.ContainerFromIndex(i);
if (listViewItem != null)
{
var rootStackPanel = VisualTreeTraverseHelper.FindDescendant <StackPanel>(listViewItem);
if (rootStackPanel != null)
{
foreach (var child in rootStackPanel.Children)
{
var frameworkElement = child as FrameworkElement;
if (frameworkElement != null)
{
frameworkElement.Width = maxValue;
_numberOfChildren++;
}
}
}
}
}
// calculates width of whole item
_totalChildWidth = Math.Round(((maxValue * _numberOfChildren) + ADDITIONAL_SPACE), DECIMAL_PLACES);
// this must be called in order to re-calculate
// each child size that it's needed to display
foreach (UIElement child in InternalChildren)
{
child.Measure(new Size(_totalChildWidth, child.DesiredSize.Height));
}
}
}
// final screen positioning
foreach (UIElement child in InternalChildren)
{
// set child position on the screen
// since location.Y has been incremented
// each child will stack vertically
child.Arrange(new Rect(location, child.DesiredSize));
location.Y += child.DesiredSize.Height;
}
return(finalSize);
}
// Control authors who want to customize the arrange pass of layout processing should
// override this method. The implementation pattern should call Arrange(Rect) on each visible child element,
// and pass the final desired size for each child element as the finalRect parameter. Parent elements should
// call Arrange(Rect) on each child, otherwise the child elements will not be rendered.
protected override Size ArrangeOverride(Size finalSize)
{
var location = new Point();
var listOfNotStretchedItemsWidth = new List <double>();
var numberOfHorizontalStretched = 0;
var lengthOfItemsControlItems = 0;
var totalParentWidth = 0.0;
var widthOfStretchedItem = 0.0;
// iterate through itemscontrol children in order
// to check how many of these children have horizontalaligmnent
// set to stretched. These calculations are needed to split available
// width into equal parts among stretched children
var listView = VisualTreeTraverseHelper.FindParent <ListView>(this.TemplatedParent);
if (listView != null && listView.Items != null)
{
for (int i = 0; i < listView.Items.Count; i++)
{
// generate container from particular index
// to check if it's stretched or not
var childContainer = listView.ItemContainerGenerator.ContainerFromIndex(i) as FrameworkElement;
if (childContainer != null)
{
// change thickness depending on thickness
// that was given by us through dependency
// property called 'Spacing'
if (this.Orientation != Orientation.Vertical)
{
if ((Spacing.Right > 0 || Spacing.Left > 0) && i < listView.Items.Count)
{
childContainer.Margin = new Thickness(Spacing.Left, 0, Spacing.Right, 0);
}
}
else
{
if ((Spacing.Top > 0 || Spacing.Bottom > 0) && i < listView.Items.Count - 1)
{
childContainer.Margin = new Thickness(0, Spacing.Top, 0, Spacing.Bottom);
}
}
// if container has stretched alignment then
// increment given value for further calculations
if (childContainer.HorizontalAlignment == HorizontalAlignment.Stretch)
{
numberOfHorizontalStretched++;
}
else
{
// store width of non-stretched items
// to calculate a proper logic for
// the stretched once.
listOfNotStretchedItemsWidth.Add(childContainer.DesiredSize.Width);
}
}
}
// get number of stretched children
lengthOfItemsControlItems = numberOfHorizontalStretched;
}
// setting up HorizontalAlighment on the control itself to stretch
// will make sure that the finalSize.Width is equal to the maximum
// available size. It will fit it's parent.
totalParentWidth = finalSize.Width;
// if there's children with different state
// of horizontalalignment then remove previously
// stored widths from the totalParentWidths
// in order to split stretched children into equal parts.
if (listOfNotStretchedItemsWidth.Count > 0)
{
foreach (var element in listOfNotStretchedItemsWidth)
{
totalParentWidth -= element;
}
}
// divide width for stretched child into
// equal parts among each stretched item.
widthOfStretchedItem = totalParentWidth / lengthOfItemsControlItems;
// iterate through internal children to
// set desired size and to call Arrange() method.
foreach (UIElement child in InternalChildren)
{
// change the location (placement) of an item
// depending of the orientation dependency property
if (Orientation != Orientation.Vertical)
{
// set the rectangle that will be a direct container
// for our child and add same width to the location
child.Arrange(new Rect(location, new Size(widthOfStretchedItem, child.DesiredSize.Height)));
if (Spacing.Right > 0 || Spacing.Left > 0)
{
location.X += widthOfStretchedItem + Math.Max(Spacing.Right, Spacing.Left);
}
else
{
location.X += widthOfStretchedItem;
}
}
else
{
child.Arrange(new Rect(location, child.DesiredSize));
if (Spacing.Top > 0 || Spacing.Bottom > 0)
{
location.X += widthOfStretchedItem + Math.Max(Spacing.Top, Spacing.Bottom);
}
else
{
location.Y += child.DesiredSize.Height;
}
}
}
return(finalSize);
}