Lnpopupcontroller: RTL support

[amosavian]

Hi,

I think LNPopupController can't handle right to left layout, This is the result of my test with pseudolanguage mode in XCode

[LeoNatan]

Thanks for reporting!
I will look at this soon.

[amosavian]

I've added this line to my source to disable RTL and it worked, until there is a real fix. It works on iOS 9+:

UIView.appearance(whenContainedInInstancesOf: [LNPopupBar.self]).semanticContentAttribute = .forceLeftToRight

[[UIView appearanceWhenContainedInInstancesOfClasses:@[[LNPopupBar class]]] setSemanticContentAttribute:UISemanticContentAttributeForceLeftToRight];

[LeoNatan]

Looking at Apple’s implementation, I see an interesting result:

The bar is flipped but the buttons are in the same order. So I need to expose granularity for both and layout accordingly. What should be the defaults?

[amosavian]

I believe we should do it based on semanticContentAttribute. if it's set to .playback, then apple's layout should be considered. If it's .forceLeftToRight the result must be same as .playback. .forceRightToLeft must change the order and .unspecified must respect UIView's direction.

We can define a separate property for UIBarButton, like barSemanticContentAttribute, or simply respects LNPopupBar.view's semantic

.playback will change image and labels direction while don't touch bar items. .forceLeftToRight and .forceRightToLeft will force left direction for both. .unspecified will respect UIView's direction.

[LeoNatan]

I've implemented this and will release a new version soon.

[LeoNatan]

Hm, so doing final checks and I found a bug in iOS 11. Setting the semanticContentAttribute of a toolbar seems to not affect how it layouts its items. So, if the app is in LTR UI and I use UISemanticContentAttributeForceRightToLeft, it breaks the layout.

[amosavian]

You don't use autolayout as I checked the code.
About toolbar, it uses autolayout on iOS 11 and this can be a bug

[LeoNatan]

I don't use AutoLayout. I enhanced my layout code to support RTL. Now, the result is funny, all the manual stuff is layout correctly for RTL or LTR according to semanticContentAttribute except for the toolbar I use internally. iOS 11 is such a shit release.
Reproduced independently in a demo project and opened a radar.

[LeoNatan]

I am trying to reverse engineer the toolbar implementation on iOS 11 to make it work correctly.

[LeoNatan]

I think I found something. Internally, UIToolbar now uses a custom UIStackView subclass to layout the items. That stack view is not forwarded the toolbar's semanticContentAttribute. If I set it manually to UISemanticContentAttributeForceRightToLeft, the items are flipped as expected, but the layout is broken.

[amosavian]

Apple's internal implementations are dirty. I've added a dozen of workarounds to address different iOS bugs.

I suggest you to subclass toolbar and use [[UIView appearanceWhenContainedInInstancesOfClasses:@[[LNPopupBarToolbar class]]] setSemanticContentAttribute:semantic]

[LeoNatan]

Yes! I think I made it work!

[LeoNatan]

I basically forced Apple's hand and enforced the attribute myself. It now works properly on iOS 10 and 11.

[LeoNatan]

semanticContentAttribute is not marked as UI_APPEARANCE_SELECTOR so it should not be used using the appearance API.

[amosavian]

It works with UIAppearance in my tests pretty good

[LeoNatan]

Still, you shouldn't. It works coincidentally due to how the appearance API is implemented, but there is no guarantee it won't break under certain conditions or in a future release.

[LeoNatan]

I'll push this soon as a minor version to the 2.5.x train. I have not found much time to continue working on the other stuff for 3.0.

[amosavian]

Thanks a lot.

[LeoNatan]

Out: https://github.com/LeoNatan/LNPopupController/releases/tag/v2.5.9
Please test and open more issues if you see any RTL problems.

[RazeeHJ]

I am using RTL, the UIBarButtonItem is positioned correctly however the Title and Subtitle is not, it's just next to the UIBarButtonItem on the right side of it while I want it to be pushed to right side corner of the tab UIBar. How can I solve this?

[LeoNatan]

Please do not bump closed old issues. Open a new issue with your question. Thank you