Fixes #2539. Menu should use Frame instead of DrawFrame.

[BDisp]

Fixes #2539 - Include a terse summary of the change or which issue is fixed.

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[tig]

Hero!

At some point, it seems Menu would be better off just being a view where each menu item is just a View (a Label?). Each 'frame' (e.g. separators) the menu would then be those View's Border.

[BDisp]

Well I was very lazy and I only used the view frame and the internal menu separator by changing the coordinates, but it could also be in the way you point to.

[tig]

Well your lazyness just caused me a bunch of work because I assumed you had done it carefully. 😠 💘

I'm merging #2483 now, but you'll see me merging in this PR into it broke some Menu tests that I had to disable because I ran out of time.. I'd love it if you'd look at them.

Menu.cs will be about 30% shorter if it can be made to fully leverage LineCanvas.

Thanks.

[BDisp]

@tig in the case of the Menu there is no need to use LineCanvas, with Frame it works well. Beside that I must understand better how it works. I'll see the unit tests.

[BDisp]

@tig you are mixing Frame with LineCanvas. Also the OnRenderLineCanvas must be call at the beginning of the Draw. What is bad in your design is that you are drawing the Border after the subviews content are drawn. To draw normal frame the Frame is more than sufficient. If you want join borders then we must use the LineCanvas, but using both in the same view is very stranger.

[BDisp]

@tig I swear I already had the menu to work before but something broke it. Is it not possible to draw a simple edge around the view frame? Run UICatalog and you'll see the menu is working as expected.

[tig]

@tig you are mixing Frame with LineCanvas. Also the OnRenderLineCanvas must be call at the beginning of the Draw. What is bad in your design is that you are drawing the Border after the subviews content are drawn. To draw normal frame the Frame is ore than sufficient. If you want join borders then we must use the LineCanvas, but using both in the same view is very stranger.

My design is not fully implemented yet. If you read the spec you'll see that.

When this is all complete the Frames will be drawn INDEPENDENTLY and BEFORE the View's content is drawn.

See #2482

[BDisp]

Hero!

At some point, it seems Menu would be better off just being a view where each menu item is just a View (a Label?). Each 'frame' (e.g. separators) the menu would then be those View's Border.

I understand what you mean, but it will imply a full refactor on the Menu which I don't know if it worth. I'll add the enable/disable border feature in the menus.

[BDisp]

For those much more brave than me here is a suggestion for two items without separator (remember that each member is a View):

┌───────┐
│ One   │
└───────┘
┌───────┐
│ Two   │
└───────┘

Since there is no separator the bottom thickness of the One item must be 0 and the top thickness of the Two item must also be 0. This will result the follow output:

┌───────┐
│ One   │
│ Two   │
└───────┘

More harder is when a separator is needed. In this case the bottom thickness of the One item must be 1 (default) and the top thickness of the Two item must be 0. This will result the follow output:

┌───────┐
│ One   │
└───────┘
│ Two   │
└───────┘

But the job isn't finished yet. It's needed to join the left with a ├ and on the right with a ┤ and the final result will be the follow output:

┌───────┐
│ One   │
├───────┤
│ Two   │
└───────┘

I don't want to give any lesson to anyone, but I only alert for the complexity, not for the steps above, but to the views that must be added to the superview and beside dealing with all menu/sub-menus opened, we needed to handle more much more views than currently has.

[tig]

The whole point of my latest big pr was to make two views that touch blend borders automatically!

Just set UseSuperviewLineCanvas = true