Question

我有一个类，它的子类是UIAccessibilityElement，目的是在我的Cocos2D应用程序中启用辅助功能。

在运行时，这个类的实例都可以通过iOS的辅助功能导航，这很棒，但我有一个特定的需求，可以改变iOS使用的语言和口音（这只适用于iOS7 + ）对于每个元素。

我注意到要做到这一点，我应该覆盖：

- (NSString*) accessibilityElementLanguage;

消息，我已经完成了。

我已通过模拟器中的辅助功能检查器确认正在返回正确的语言ID（它将显示在检查器中）。

当画外音读取与该元素相关联的文本时，它坚持使用默认设备语音和语言，因此西班牙语单词听起来完全不正确。

我不确定我做错了什么。当语言设置无法工作时，我尝试了一种解决方法，我将处理accessibilityElementDidBecomeFocused回调并使用我自己的代码读取文本，但现在我甚至没有获得焦点事件的回调，除非我运行模拟器与辅助功能检查器已启用，我触摸了其中一个元素。

我确信这里有一些简单的错误。任何帮助将不胜感激。

类接口的代码是：

#import <UIKit/UIKit.h>
#import "CCSwitchableNode.h"
#import <UIKit/UIAccessibility.h>

@interface AccessibleSwitchableNode : UIAccessibilityElement <UIAccessibilityIdentification>

- (id) initWithNode:(id<CCSwitchableNode>)node inContainer:(id)container;

+ (AccessibleSwitchableNode*) accessibleSwitchableWithNode:(id<CCSwitchableNode>)node inContainer:(id)container;

@property (nonatomic, retain) id<CCSwitchableNode> node;

@end

实施：

#import "AccessibleSwitchableNode.h"
#import <UIKit/UIAccessibility.h>
#import <UIKit/UIAccessibilityElement.h>

@implementation AccessibleSwitchableNode {

    BOOL isFocused_Local;

}

- (id) initWithNode:(id<CCSwitchableNode>)node inContainer:(id)container {
    self = [super initWithAccessibilityContainer:container];

    if (self != nil) {
        isFocused_Local = NO;

        self.node = node;

        // This code is a quick hack to translate the position from Cocos2d in one specific orientation
        // to UIKit.  To be finessed.
        //
        CGPoint uiPoint = [[CCDirector sharedDirector] convertToUI:[node switchableNodePosition]];
        uiPoint.x = [CocosUtil screenWidth] - uiPoint.x;

        self.accessibilityFrame =
        CGRectMake(uiPoint.y-([node switchableNodeSize].height/2.0f),
                   uiPoint.x-([node switchableNodeSize].width/2.0f),
                   [node switchableNodeSize].height,
                   [node switchableNodeSize].width);

        self.accessibilityLabel = [node textForSpeaking];
        self.accessibilityValue = [node textForSpeaking];
        self.accessibilityTraits = UIAccessibilityTraitButton;
        self.accessibilityActivationPoint = CGPointMake(uiPoint.y, uiPoint.x);
    }

    return self;
}

+ (AccessibleSwitchableNode*) accessibleSwitchableWithNode:(id<CCSwitchableNode>)node inContainer:(id)container {
    return [[[AccessibleSwitchableNode alloc] initWithNode:node inContainer:container] autorelease];
}

- (void) dealloc {
    self.node = nil;

    [super dealloc];
}

// Called when the object is first added, but has no effect on pronunciation.
//
- (NSString*) accessibilityLanguage {
    return [self.node languageForText];
}

// Never called unless on the simulator with the inspector active.
//
- (void) accessibilityElementDidBecomeFocused {
    NSLog(@"accessibilityElementDidBecomeFocusedd: %@", self.accessibilityLabel);
    isFocused_Local = YES;
}

// Never called unless on the simulator with the inspector active.
//
- (void) accessibilityElementDidLoseFocus {
    NSLog(@"accessibilityElementDidLoseFocus: %@", self.accessibilityLabel);
    isFocused_Local = NO;
}

// Never called unless on the simulator with the inspector active.
//
- (BOOL) accessibilityElementIsFocused {
    NSLog(@"accessibilityElementIsFocused: %@", self.accessibilityLabel);
    return isFocused_Local;
}

// Never called unless on the simulator with the inspector active.
//
- (BOOL) accessibilityActivate {
    if ([self.node isSwitchSelectable] == YES) {
        [self.node switchSelect];

        return YES;
    } else {
        return NO;
    }
}

- (BOOL) isAccessibilityElement {
    return [self.node isSwitchSelectable];
}

@end

我要添加到AccessibilityElements的Cocos2D节点的协议是：

#import <Foundation/Foundation.h>

@protocol CCSwitchableNode <NSObject>

// Should return the size of the node on screen.
//
- (CGSize) switchableNodeSize;

// Should return the position (center) of the node in screen coordinates.
//
- (CGPoint) switchableNodePosition;

// Should return YES if the node is currently able to accept taps by the user.
//
- (BOOL) isSwitchSelectable;

// Should cause the node, be it a button of some sort, or something else, to act as if it has been
// tapped.  This will be called when a switch is used to "select" an item on the screen.
//
- (void) switchSelect;

// Should return YES if the node would prefer to highlight itself to the user as selectable.  If this
// happens, the SwitchControlLayer will call the setSwitchHighlighted: as appropriate in
// order to turn on or off the highlight.
//
- (BOOL) hasOwnHighlight;

// Should return a NSString containing the text to be spoken when the node is highlighted.  If no text is
// to be spoken, then nil should be returned.
//
- (NSString*) textForSpeaking;

// Should return a NSString containing the language locale to use when speaking the nodes text.
//
- (NSString*) languageForText;

@optional

// This optional method should be implemented in classes that can return YES from the hasOwnHighlight
// method.  The SwitchControlLayer will call this instead of using it's own built-in highlight
// to turn on, or off the highlight.
//
- (void) setSwitchHighlighted:(BOOL)highlighted;

@end

Answer 1

这可能会让你感到惊讶和恐惧，但即便是苹果公司也会出现问题。如果您遇到意外或主观上的错误＆＃34;通过全面的复制步骤和示例项目，考虑 filing a Radar 。

Answer 2

根据我上面的一些评论，简短的回答是iOS7不像VoiceOver那样支持Switch Control的各种回调和API。适用于VoiceOver的功能不一定适用于Switch Control。

向Apple提交了一个错误，并在那里与他们进行了互动，针对iOS8测试我的代码表明，对于Switch Control的支持已经改进了beta 5，但仍然不完整。 accessibilityElementDidBecomeFocused回调现在似乎可以正常工作，但是Switch Control仍然拒绝使用accessibilityElementLanguage回调。

未调用UIAccessibilityElement回调

2 个答案: