Fixes #2983. View need a alternative DrawFrame for the v2.

[BDisp]

Fixes #2983 - Use LineCanvas to draw the frame and supersede the obsolete method.

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[BDisp]

@tig the obsolete Frame.DrawFrame(Rect, bool) isn't using anymore and maybe can be removed?

[tig]

See my comments and questions.

[tznind]

I'm looking at DrawIncompleteFrame and thinking there might be a simpler way to achieve this and create a lot more flexibility for other things. Here is my premise

Add a method which returns just the lines for the rect:

public IEnumerable<StraightLine> GetFrame (Rect rect, LineStyle lineStyle, Attribute? attribute = null)
{
	var vts = ViewToScreen (rect);			
	yield return new StraightLine(new Point (vts.X, vts.Y), vts.Width,
		Orientation.Horizontal, lineStyle, attribute);
	yield return new StraightLine (new Point (vts.Right - 1, vts.Y), vts.Height,
		Orientation.Vertical, lineStyle, attribute);
	yield return new StraightLine (new Point (vts.Right - 1, vts.Bottom - 1), -vts.Width,
		Orientation.Horizontal, lineStyle, attribute);
	yield return new StraightLine (new Point (vts.X, vts.Bottom - 1), -vts.Height,
		Orientation.Vertical, lineStyle, attribute);
}

Add an extension method that operates on a collection of lines that lets you create an exclusion area:

public static class StraightLineExtensions
{
/// <summary>
	/// Splits or removes all lines in the <paramref name="collection"/> such that none cover the given
	/// exclusion area.
	/// </summary>
	/// <param name="collection">Lines to adjust</param>
	/// <param name="start">First point to remove from collection</param>
	/// <param name="length">The number of sequential points to exclude</param>
	/// <param name="orientation">Orientation of the exclusion line</param>
	/// <returns></returns>
	public static IEnumerable<StraightLine> Exclude (this IEnumerable<StraightLine> collection, Point start, int length, Orientation orientation)
	{
		foreach(var l in collection) {

			// if line intersects the exclusion

			// if it is wholly inclusive of the line
				// remove it from returned collection
			// else if it is longer on both ends
				// split l into two lines
			// else
				// shorten right or left
		}

		return collection;
	}
}

What do you think? this would let you create rectangles with gaps in any sides needed and many other cool things besides?

I can probably work out the code for this method if its a go?

[BDisp]

What do you think? this would let you create rectangles with gaps in any sides needed and many other cool things besides?

I can probably work out the code for this method if its a go?

Any help is welcome. The DrawIncompleteFrame know where the side start and where the side end. It also allow to create rectangles with gaps in any sides needed by calling several times with different locations by using the same bounds. But any reduce of code is always better and more cleaning. So, the idea of exclusions is very good.
For now I have some TabView unit test failing.
Feel free to do what you think is better. Thanks.

[tznind]

@BDisp I have created #3004 as an alternative approach to DrawIncompleteFrame which can hopefully simplify things. Let me know what you think.

[BDisp]

@BDisp I have created #3004 as an alternative approach to DrawIncompleteFrame which can hopefully simplify things. Let me know what you think.

I like it very much. More elegant and with less code. Thanks.

In this PR I'm using a non 0 location with a value of 3 to avoid be divisible by 2 and so avoiding bugs on the unit tests. I never more will be using the 0 location for unit tests with frame.

[BDisp]

Closing this because was supersede per the #3004.