ios - 未调用 UIAccessibilityElement 回调

Question

我有一个类，它是 UIAccessibilityElement 的子类，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 的辅助功能进行导航，这很好，但我有一个特定的需要能够更改 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。

我已经通过模拟器中的辅助功能检查器确认返回了正确的语言 ID(它显示在检查器中)。

然而，当画外音朗读与该元素关联的文本时，它坚持使用默认的设备语音和语言，因此西类牙语单词听起来完全不正确是可以理解的。

我不确定我做错了什么。当语言设置失败时，我尝试了一种解决方法，即我将处理 accessibilityElementDidBecomeFocused 回调并使用我自己的代码读取文本，但现在我什至没有获得焦点事件的回调，除非我使用可访问性检查器已启用，我触摸了我的元素之一。

我确定我这里有一些简单的错误。任何帮助将不胜感激。

类接口(interface)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

和实现:

#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

我添加到 AccessibilityElements 的 Cocos2D 节点的协议(protocol)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

这可能会让您感到惊讶和害怕，但即使是 Apple 也有漏洞。如果您遇到意外或主观上“错误”的行为，请考虑 filing a Radar 具有全面的复制步骤和示例项目。