src/Files.App/Helpers/UI/DragZoneHelper.cs - main - githubmirror/Files

src/Files.App/Helpers/UI/DragZoneHelper.cs
64 строки3 KB
Yair
Code Quality: Ran code cleanup (#17307)
25 июл 2025, 03:57
25 июл 2025, 03:574558bc2
// Copyright (c) Files Community
// Licensed under the MIT License.

using Microsoft.UI.Input;
using Microsoft.UI.Xaml;
using Windows.Graphics;

namespace Files.App.Helpers
{
	public static class DragZoneHelper
	{
		public delegate int SetTitleBarDragRegionDelegate(InputNonClientPointerSource source, SizeInt32 size, double scaleFactor, Func<UIElement, RectInt32?, RectInt32> getScaledRect);

		/// <summary>
		/// Informs the bearer to refresh the drag region.
		/// will not set<see cref="NonClientRegionKind.LeftBorder"/>, <see cref="NonClientRegionKind.RightBorder"/>, <see cref="NonClientRegionKind.Caption"/>when titleBarHeight less than 0
		/// </summary>
		/// <param name="element"></param>
		/// <param name="window"></param>
		/// <param name="setTitleBarDragRegion"></param>
		public static void RaiseSetTitleBarDragRegion(this Window window, SetTitleBarDragRegionDelegate setTitleBarDragRegion)
		{
			if (!window.AppWindow.IsVisible)
				return;
			// UIElement.RasterizationScale is always 1
			var source = InputNonClientPointerSource.GetForWindowId(window.AppWindow.Id);
			var uiElement = window.Content;
			var xamlRoot = uiElement?.XamlRoot;

			if (xamlRoot is null)
				return;

			var scaleFactor = xamlRoot.RasterizationScale;
			var size = window.AppWindow.Size;
			// If the number of regions is 0 or 1, AppWindow will automatically reset to the default region next time, but if it is >=2, it will not and need to be manually cleared
			source.ClearRegionRects(NonClientRegionKind.Passthrough);
			var titleBarHeight = setTitleBarDragRegion(source, size, scaleFactor, GetScaledRect);
			if (titleBarHeight >= 0)
			{
				// region under the buttons
				const int borderThickness = 5;
				source.SetRegionRects(NonClientRegionKind.LeftBorder, [GetScaledRect(uiElement, new(0, 0, borderThickness, titleBarHeight))]);
				source.SetRegionRects(NonClientRegionKind.RightBorder, [GetScaledRect(uiElement, new(size.Width, 0, borderThickness, titleBarHeight))]);
				source.SetRegionRects(NonClientRegionKind.Caption, [GetScaledRect(uiElement, new(0, 0, size.Width, titleBarHeight))]);
			}
		}

		private static RectInt32 GetScaledRect(this UIElement uiElement, RectInt32? r = null)
		{
			if (r is { } rect)
			{
				var scaleFactor = uiElement.XamlRoot.RasterizationScale;
				return new((int)(rect.X * scaleFactor), (int)(rect.Y * scaleFactor), (int)(rect.Width * scaleFactor),
					(int)(rect.Height * scaleFactor));
			}
			else
			{
				var pos = uiElement.TransformToVisual(null).TransformPoint(new(0, 0));
				rect = new RectInt32((int)pos.X, (int)pos.Y, (int)uiElement.ActualSize.X, (int)uiElement.ActualSize.Y);
				return GetScaledRect(uiElement, rect);
			}
		}
	}
}