private void RectangleSelection_PointerPressed(object sender, PointerRoutedEventArgs e)
{
itemsPosition.Clear();
originDragPoint = new Point(e.GetCurrentPoint(uiElement).Position.X, e.GetCurrentPoint(uiElement).Position.Y); // Initial drag point relative to the topleft corner
prevSelectedItems = uiElement.SelectedItems.Cast <object>().ToList(); // Save current selected items
var verticalOffset = scrollViewer?.VerticalOffset ?? 0;
originDragPoint.Y += verticalOffset; // Initial drag point relative to the top of the list (considering scrolled offset)
if (!e.GetCurrentPoint(uiElement).Properties.IsLeftButtonPressed || e.Pointer.PointerDeviceType == Windows.Devices.Input.PointerDeviceType.Touch)
{
// Trigger only on left click, do not trigger with touch
return;
}
selectionStrategy = e.KeyModifiers.HasFlag(VirtualKeyModifiers.Control) ?
new InvertPreviousItemSelectionStrategy(uiElement.SelectedItems, prevSelectedItems) :
e.KeyModifiers.HasFlag(VirtualKeyModifiers.Shift) ?
(ItemSelectionStrategy) new ExtendPreviousItemSelectionStrategy(uiElement.SelectedItems, prevSelectedItems) :
new IgnorePreviousItemSelectionStrategy(uiElement.SelectedItems);
selectionStrategy.HandleNoItemSelected();
uiElement.PointerMoved -= RectangleSelection_PointerMoved;
uiElement.PointerMoved += RectangleSelection_PointerMoved;
if (selectionChanged != null)
{
// Unsunscribe from SelectionChanged event for performance
uiElement.SelectionChanged -= selectionChanged;
}
uiElement.CapturePointer(e.Pointer);
selectionState = SelectionState.Starting;
}
private void RectangleSelection_PointerPressed(object sender, PointerRoutedEventArgs e)
{
itemsPosition.Clear();
dataGridRows.Clear();
DependencyObjectHelpers.FindChildren <DataGridRow>(dataGridRows, uiElement); // Find visible/loaded rows
prevSelectedItems = uiElement.SelectedItems.Cast <object>().ToList(); // Save current selected items
originDragPoint = new Point(e.GetCurrentPoint(uiElement).Position.X, e.GetCurrentPoint(uiElement).Position.Y); // Initial drag point relative to the topleft corner
var verticalOffset = (scrollBar?.Value ?? 0) - uiElement.ColumnHeaderHeight;
originDragPoint.Y += verticalOffset; // Initial drag point relative to the top of the list (considering scrolled offset)
if (!e.GetCurrentPoint(uiElement).Properties.IsLeftButtonPressed || e.Pointer.PointerDeviceType == Windows.Devices.Input.PointerDeviceType.Touch)
{
// Trigger only on left click, do not trigger with touch
return;
}
var clickedRow = DependencyObjectHelpers.FindParent <DataGridRow>(e.OriginalSource as DependencyObject);
if (clickedRow != null && uiElement.SelectedItems.Contains(clickedRow.DataContext))
{
// If the item under the pointer is selected do not trigger selection rectangle
return;
}
var selectedItems = new GenericItemsCollection <object>(uiElement.SelectedItems);
selectionStrategy = e.KeyModifiers.HasFlag(VirtualKeyModifiers.Control) ?
new InvertPreviousItemSelectionStrategy(selectedItems, prevSelectedItems) :
e.KeyModifiers.HasFlag(VirtualKeyModifiers.Shift) ?
(ItemSelectionStrategy) new ExtendPreviousItemSelectionStrategy(selectedItems, prevSelectedItems) :
new IgnorePreviousItemSelectionStrategy(selectedItems);
if (clickedRow == null)
{
// If user click outside, reset selection
if (uiElement.CurrentColumn != null)
{
uiElement.CancelEdit();
}
DeselectGridCell();
selectionStrategy.HandleNoItemSelected();
}
uiElement.PointerMoved -= RectangleSelection_PointerMoved;
uiElement.PointerMoved += RectangleSelection_PointerMoved;
if (selectionChanged != null)
{
// Unsunscribe from SelectionChanged event for performance
uiElement.SelectionChanged -= selectionChanged;
}
uiElement.CapturePointer(e.Pointer);
selectionState = SelectionState.Starting;
}