iOS 9 disable support for right-to-left language

问题:

My iOS app is in Arabic (right-to-left) language only. Prior to iOS 9 the views layout and view animations were all by default left-to-right. So, I had customised the complete app and had reversed the default behaviour e.g. back button in navigation bar was set to be on the right instead of default left.

But now when the app is compiled using latest SDK (Xcode 7 beta 4), everything is the opposite of what I need.

Is there any simple way to force the app to show views and behave like iOS 8 and 7?

I searched and found a solution but it involves changing the constraints(Uncheck the "Respect language direction") for all views. But this is not a feasible solution in large projects.

This is a screenshot after compiling with Xcode 7 beta 4.

and this is a screenshot when compiled with Xcode 6.

回答1:

Edit: The following code may cause unexpected behavior as @wakachamo pointed out. So, please watch out for issues e.g. Interactive pop gesture doesn't work, alertviews don't show, etc. Its better to follow the instruction provided by @wakachamo if this doesn't work for you

Add this to app delegate didFinishLaunchingWithOptions method.

[[UIView appearance] setSemanticContentAttribute:UISemanticContentAttributeForceLeftToRight];

Also add guard to support earlier version so that the property doesn't cause any crash.

if([[[UIView alloc] init] respondsToSelector:@selector(setSemanticContentAttribute:)]) {
        [[UIView appearance] setSemanticContentAttribute:UISemanticContentAttributeForceLeftToRight];
    }

[[UIView alloc] init] instead of [UIView appearance] because respondsToSelector is not currently working with [UIView appearance] for setSemanticContentAttribute. You can also add iOS 9 Check

#define SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(v)  ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] != NSOrderedAscending)

if(SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(@"9.0")) {
        [[UIView appearance] setSemanticContentAttribute:UISemanticContentAttributeForceLeftToRight];
    }

回答2:

i found the correct way from Apple Developer Forums

here iOS 9 beta - UIAlertController is not working

just add this code to make alertview work with it

 if(SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(@"9.0")) {
            [[UIView appearance] setSemanticContentAttribute:UISemanticContentAttributeForceLeftToRight];

    [[UIView appearanceWhenContainedIn:[UIAlertController class], nil] setSemanticContentAttribute:UISemanticContentAttributeUnspecified];
    [[UIView appearanceWhenContainedIn:[UIAlertView class], nil] setSemanticContentAttribute:UISemanticContentAttributeUnspecified];



}

回答3:

I know its too late to answer. But I have figured it out (Only the navigation bar issue).

The answer is adapted from @Kamran Kan. Thanks @Kamran.

Jus replace the UIView with UINavigationBar in @Kamran's answer. then the code will be as follows.

#define SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(v)  ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] != NSOrderedAscending)

if(SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(@"9.0")) {
    [[UINavigationBar appearance] setSemanticContentAttribute:UISemanticContentAttributeForceLeftToRight];
}

Since it is only effect the UINavigationBar, the other controls won't effect. So the UIAlertView is working fine...

回答4:

There is no easy way. It's recommended that you migrate to standard API as much as possible long-term.

Another approach is to set the semanticContentAttribute of all the affected views to UISemanticContentAttributeForceLeftToRight, but this is just as feasible as setting all your constraints to use Left/Right instead of Leading/Trailing. In addition to this, you'll also have to gate these calls around an availability check if you're targeting iOS <9.

回答5:

SWIFT 2 Code

if #available(iOS 9.0, *) {
     myView.semanticContentAttribute = .ForceLeftToRight
}

回答6:

For SWIFT 3

if #available(iOS 10.0, *) {
     UIView.appearance().semanticContentAttribute = .forceLeftToRight
}

回答7:

Use Storyboard and choose for each specific view controllers

Semantic->Force Left-to-Right.