twui/lib/UIKit/TUIAccessibility.m

/*
 Copyright 2011 Twitter, Inc.
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this work except in compliance with the License.
 You may obtain a copy of the License in the LICENSE file, or at:
 
 http://www.apache.org/licenses/LICENSE-2.0
 
 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
 */

#import "TUIAccessibility.h"

TUIAccessibilityTraits TUIAccessibilityTraitNone = 1 << 0;
TUIAccessibilityTraits TUIAccessibilityTraitButton = 1 << 1;
TUIAccessibilityTraits TUIAccessibilityTraitLink = 1 << 2;
TUIAccessibilityTraits TUIAccessibilityTraitSearchField = 1 << 3;
TUIAccessibilityTraits TUIAccessibilityTraitImage = 1 << 4;
TUIAccessibilityTraits TUIAccessibilityTraitSelected = 1 << 5;
TUIAccessibilityTraits TUIAccessibilityTraitPlaysSound = 1 << 6;
TUIAccessibilityTraits TUIAccessibilityTraitStaticText = 1 << 7;
TUIAccessibilityTraits TUIAccessibilityTraitSummaryElement = 1 << 8;
TUIAccessibilityTraits TUIAccessibilityTraitNotEnabled = 1 << 9;
TUIAccessibilityTraits TUIAccessibilityTraitUpdatesFrequently = 1 << 10;

@implementation NSObject (TUIAccessibility)

- (BOOL)isAccessibilityElement
{
    return NO;
}

- (void)setIsAccessibilityElement:(BOOL)isElement
{
	
}

- (NSString *)accessibilityLabel
{
    return nil;
}

- (void)setAccessibilityLabel:(NSString *)label
{
	
}

- (NSString *)accessibilityHint
{
    return nil;
}

- (void)setAccessibilityHint:(NSString *)hint
{
	
}

- (NSString *)accessibilityValue
{
    return nil;
}

- (void)setAccessibilityValue:(NSString *)value
{
	
}

- (TUIAccessibilityTraits)accessibilityTraits
{
    return TUIAccessibilityTraitNone;
}

- (void)setAccessibilityTraits:(TUIAccessibilityTraits)traits
{

}

- (CGRect)accessibilityFrame
{
    return CGRectNull;
}

- (void)setAccessibilityFrame:(CGRect)frame
{
	
}


#pragma mark NSAccessibility

// This is the part where we transate TUIAccessibility values into something that NSAccessibility can understand. Hopefully.

- (NSArray *)accessibilityAttributeNames
{
    static NSArray *attributes = nil;
    if(attributes == nil) {
		attributes = [[NSArray alloc] initWithObjects:NSAccessibilityRoleAttribute, NSAccessibilityRoleDescriptionAttribute, NSAccessibilityFocusedAttribute, NSAccessibilityParentAttribute, NSAccessibilityWindowAttribute, NSAccessibilityTopLevelUIElementAttribute, NSAccessibilityPositionAttribute, NSAccessibilitySizeAttribute, nil];
    }
	
    return attributes;
}

- (id)accessibilityAttributeValue:(NSString *)attribute
{
    if([attribute isEqualToString:NSAccessibilityRoleAttribute]) {
		return @"radioButton";
    } else if([attribute isEqualToString:NSAccessibilityRoleDescriptionAttribute]) {
		return @"radio button"; //NSAccessibilityRoleDescription(role, nil);
    } else if([attribute isEqualToString:NSAccessibilityFocusedAttribute]) {
		// Just check if the app thinks we're focused.
		id focusedElement = [NSApp accessibilityAttributeValue:NSAccessibilityFocusedUIElementAttribute];
		return [NSNumber numberWithBool:[focusedElement isEqual:self]];
    } else if([attribute isEqualToString:NSAccessibilityParentAttribute]) {
		return nil; //NSAccessibilityUnignoredAncestor(parent);
    } else if([attribute isEqualToString:NSAccessibilityWindowAttribute]) {
		// We're in the same window as our parent.
		return nil; //[parent accessibilityAttributeValue:NSAccessibilityWindowAttribute];
    } else if([attribute isEqualToString:NSAccessibilityTopLevelUIElementAttribute]) {
		// We're in the same top level element as our parent.
		return nil; //[parent accessibilityAttributeValue:NSAccessibilityTopLevelUIElementAttribute];
    } else if([attribute isEqualToString:NSAccessibilityPositionAttribute]) {
		return nil; //[NSValue valueWithPoint:[parent fauxUIElementPosition:self]];
    } else if([attribute isEqualToString:NSAccessibilitySizeAttribute]) {
		return nil; //[NSValue valueWithSize:[parent fauxUIElementSize:self]];
    } else {
		return nil;
    }
}

- (BOOL)accessibilityIsAttributeSettable:(NSString *)attribute
{
    if([attribute isEqualToString:NSAccessibilityFocusedAttribute]) {
		return NO; //[parent isFauxUIElementFocusable:self];
    } else {
		return NO;
    }
}

- (void)accessibilitySetValue:(id)value forAttribute:(NSString *)attribute
{
    if([attribute isEqualToString:NSAccessibilityFocusedAttribute]) {
		//		[parent fauxUIElement:self setFocus:value];
    }
}

- (NSArray *)accessibilityActionNames {
    return [NSArray array];
}

- (NSString *)accessibilityActionDescription:(NSString *)action {
    return nil;
}

- (void)accessibilityPerformAction:(NSString *)action {
	
}

- (BOOL)accessibilityIsIgnored {
    return ![self isAccessibilityElement];
}

- (id)accessibilityHitTest:(NSPoint)point
{
    return NSAccessibilityUnignoredAncestor(self);
}

- (id)accessibilityFocusedUIElement
{
    return NSAccessibilityUnignoredAncestor(self);
}

@end