phonegap-mobile-accessibility/src/ios/CDVMobileAccessibility.m

/*
 Licensed to the Apache Software Foundation (ASF) under one
 or more contributor license agreements.  See the NOTICE file
 distributed with this work for additional information
 regarding copyright ownership.  The ASF licenses this file
 to you under the Apache License, Version 2.0 (the
 "License"); you may not use this file except in compliance
 with the License.  You may obtain a copy of the License 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 "CDVMobileAccessibility.h"
#import <Cordova/CDVAvailability.h>
#import <MediaAccessibility/MediaAccessibility.h>

@interface CDVMobileAccessibility ()
// add any property overrides
@end

@implementation CDVMobileAccessibility

@synthesize callbackId;
@synthesize commandCallbackId;
@synthesize voiceOverRunning;
@synthesize closedCaptioningEnabled;
@synthesize guidedAccessEnabled;
@synthesize invertColorsEnabled;
@synthesize monoAudioEnabled;

// //////////////////////////////////////////////////

- (id)settingForKey:(NSString*)key
{
    return [self.commandDelegate.settings objectForKey:[key lowercaseString]];
}

- (void)pluginInitialize
{
    // SETTINGS ////////////////////////

    NSString* setting = nil;

    setting = @"YourConfigXmlSettingHere";
    if ([self settingForKey:setting]) {
        // set your setting, other init here
    }
    
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(onPause) name:UIApplicationDidEnterBackgroundNotification object:nil];
}

// //////////////////////////////////////////////////

- (void)dealloc
{
    [self stop:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIApplicationDidEnterBackgroundNotification object:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIApplicationWillEnterForegroundNotification object:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIApplicationDidBecomeActiveNotification object:nil];
}

- (void)onReset
{
    [self stop:nil];
}

- (void) onPause {
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIApplicationDidEnterBackgroundNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(onResume) name:UIApplicationWillEnterForegroundNotification object:nil];
}

- (void)onResume
{
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIApplicationWillEnterForegroundNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(onPause) name:UIApplicationDidEnterBackgroundNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(onApplicationDidBecomeActive) name:UIApplicationDidBecomeActiveNotification object:nil];
}

- (void)onApplicationDidBecomeActive
{
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIApplicationDidBecomeActiveNotification object:nil];
    [self performSelector:@selector(sendMobileAccessibilityStatusChangedCallback) withObject:nil afterDelay:0.1 ];
}

// //////////////////////////////////////////////////

#pragma Plugin interface

- (void)isScreenReaderRunning:(CDVInvokedUrlCommand*)command
{
    [self.commandDelegate runInBackground:^{
        self.voiceOverRunning = UIAccessibilityIsVoiceOverRunning();
        CDVPluginResult* result = [CDVPluginResult resultWithStatus:CDVCommandStatus_OK messageAsBool:self.voiceOverRunning];
        [self.commandDelegate sendPluginResult:result callbackId:command.callbackId];
    }];
}

- (void)isClosedCaptioningEnabled:(CDVInvokedUrlCommand*)command
{
    [self.commandDelegate runInBackground:^{
        self.closedCaptioningEnabled = [self getClosedCaptioningEnabledStatus];
        CDVPluginResult* result = [CDVPluginResult resultWithStatus:CDVCommandStatus_OK messageAsBool:self.closedCaptioningEnabled];
        [self.commandDelegate sendPluginResult:result callbackId:command.callbackId];
    }];
}

- (void)isGuidedAccessEnabled:(CDVInvokedUrlCommand*)command
{
    [self.commandDelegate runInBackground:^{
        self.guidedAccessEnabled = UIAccessibilityIsGuidedAccessEnabled();
        CDVPluginResult* result = [CDVPluginResult resultWithStatus:CDVCommandStatus_OK messageAsBool:self.guidedAccessEnabled];
        [self.commandDelegate sendPluginResult:result callbackId:command.callbackId];
    }];
}

- (void)isInvertColorsEnabled:(CDVInvokedUrlCommand*)command
{
    [self.commandDelegate runInBackground:^{
        self.invertColorsEnabled = UIAccessibilityIsInvertColorsEnabled();
        CDVPluginResult* result = [CDVPluginResult resultWithStatus:CDVCommandStatus_OK messageAsBool:self.invertColorsEnabled];
        [self.commandDelegate sendPluginResult:result callbackId:command.callbackId];
    }];
}

- (void)isMonoAudioEnabled:(CDVInvokedUrlCommand*)command
{
    [self.commandDelegate runInBackground:^{
        self.monoAudioEnabled = UIAccessibilityIsMonoAudioEnabled();
        CDVPluginResult* result = [CDVPluginResult resultWithStatus:CDVCommandStatus_OK messageAsBool:self.monoAudioEnabled];
        [self.commandDelegate sendPluginResult:result callbackId:command.callbackId];
    }];
}

- (void)postNotification:(CDVInvokedUrlCommand *)command
{
    CDVPluginResult* result = nil;
    uint32_t notificationType = [[command.arguments objectAtIndex:0] intValue];
    NSString* notificationString = [command.arguments objectAtIndex:1];
    
    if (notificationString == nil) {
        notificationString = @"";
    }
    
    if (UIAccessibilityIsVoiceOverRunning() &&
        [self isValidNotificationType:notificationType]) {
        [self.commandDelegate runInBackground:^{
            if (notificationType == UIAccessibilityAnnouncementNotification) {
                self.commandCallbackId = command.callbackId;
                [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(mobileAccessibilityAnnouncementDidFinish:) name:UIAccessibilityAnnouncementDidFinishNotification object:nil];
            }
            
            UIAccessibilityPostNotification(notificationType, notificationString);
            
            if (notificationType != UIAccessibilityAnnouncementNotification) {
                NSMutableDictionary* data = [NSMutableDictionary dictionaryWithCapacity:2];
                [data setObject:notificationString forKey:@"stringValue"];
                [data setObject:@"true" forKey:@"wasSuccessful"];
                CDVPluginResult* result = [CDVPluginResult resultWithStatus:CDVCommandStatus_OK messageAsDictionary:data];
                [self.commandDelegate sendPluginResult:result callbackId:command.callbackId];
            }
        }];
    } else {
        result = [CDVPluginResult resultWithStatus:CDVCommandStatus_ERROR];
        [self.commandDelegate sendPluginResult:result callbackId:command.callbackId];
    }
}

- (BOOL)isValidNotificationType:(uint32_t)notificationType
{
    return (notificationType == UIAccessibilityScreenChangedNotification
            || notificationType == UIAccessibilityLayoutChangedNotification
            || notificationType == UIAccessibilityAnnouncementNotification
            || notificationType == UIAccessibilityPageScrolledNotification);
}

- (void)mobileAccessibilityAnnouncementDidFinish:(NSNotification *)dict
{
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIAccessibilityAnnouncementDidFinishNotification object:nil];
    
    NSString* valueSpoken = [[dict userInfo] objectForKey:UIAccessibilityAnnouncementKeyStringValue];
    NSString* wasSuccessful = [[dict userInfo] objectForKey:UIAccessibilityAnnouncementKeyWasSuccessful];
    
    NSMutableDictionary* data = [NSMutableDictionary dictionaryWithCapacity:2];
    [data setObject:valueSpoken forKey:@"stringValue"];
    [data setObject:wasSuccessful forKey:@"wasSuccessful"];
    
    if (self.commandCallbackId) {
        CDVPluginResult* result = [CDVPluginResult resultWithStatus:CDVCommandStatus_OK messageAsDictionary:data];
        [self.commandDelegate sendPluginResult:result callbackId:self.commandCallbackId];
        self.commandCallbackId = nil;
    }
}

- (BOOL)getClosedCaptioningEnabledStatus
{
    BOOL status = false;
    if (&MACaptionAppearanceGetDisplayType) {
        status = (MACaptionAppearanceGetDisplayType(kMACaptionAppearanceDomainUser) > kMACaptionAppearanceDisplayTypeAutomatic);
    } else {
        status = UIAccessibilityIsClosedCaptioningEnabled();
    }
    return status;
}

- (void)mobileAccessibilityStatusChanged:(NSNotification *)notification
{
    [self sendMobileAccessibilityStatusChangedCallback];
}

- (void)sendMobileAccessibilityStatusChangedCallback
{
    if (self.callbackId) {
        CDVPluginResult* result = [CDVPluginResult resultWithStatus:CDVCommandStatus_OK messageAsDictionary:[self getMobileAccessibilityStatus]];
        [result setKeepCallbackAsBool:YES];
        [self.commandDelegate sendPluginResult:result callbackId:self.callbackId];
    }
}

/* Get the current mobile accessibility status. */
- (NSDictionary*)getMobileAccessibilityStatus
{
    self.voiceOverRunning = UIAccessibilityIsVoiceOverRunning();
    self.closedCaptioningEnabled = [self getClosedCaptioningEnabledStatus];
    self.guidedAccessEnabled = UIAccessibilityIsGuidedAccessEnabled();
    self.invertColorsEnabled = UIAccessibilityIsInvertColorsEnabled();
    self.monoAudioEnabled = UIAccessibilityIsMonoAudioEnabled();
    
    NSMutableDictionary* mobileAccessibilityData = [NSMutableDictionary dictionaryWithCapacity:5];
    [mobileAccessibilityData setObject:[NSNumber numberWithBool:self.voiceOverRunning] forKey:@"isScreenReaderRunning"];
    [mobileAccessibilityData setObject:[NSNumber numberWithBool:self.closedCaptioningEnabled] forKey:@"isClosedCaptioningEnabled"];
    [mobileAccessibilityData setObject:[NSNumber numberWithBool:self.guidedAccessEnabled] forKey:@"isGuidedAccessEnabled"];
    [mobileAccessibilityData setObject:[NSNumber numberWithBool:self.invertColorsEnabled] forKey:@"isInvertColorsEnabled"];
    [mobileAccessibilityData setObject:[NSNumber numberWithBool:self.monoAudioEnabled] forKey:@"isMonoAudioEnabled"];
    return mobileAccessibilityData;
}


/* start MobileAccessibility monitoring */
- (void)start:(CDVInvokedUrlCommand*)command
{
    [self.commandDelegate runInBackground:^{
        self.callbackId = command.callbackId;
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(mobileAccessibilityStatusChanged:) name:UIAccessibilityVoiceOverStatusChanged object:nil];
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(mobileAccessibilityStatusChanged:) name:UIAccessibilityClosedCaptioningStatusDidChangeNotification object:nil];
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(mobileAccessibilityStatusChanged:) name:UIAccessibilityGuidedAccessStatusDidChangeNotification object:nil];
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(mobileAccessibilityStatusChanged:) name:UIAccessibilityInvertColorsStatusDidChangeNotification object:nil];
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(mobileAccessibilityStatusChanged:) name:UIAccessibilityMonoAudioStatusDidChangeNotification object:nil];
        
        // Update the callback on start
        CDVPluginResult* result = [CDVPluginResult resultWithStatus:CDVCommandStatus_OK messageAsDictionary:[self getMobileAccessibilityStatus]];
        [result setKeepCallbackAsBool:YES];
        [self.commandDelegate sendPluginResult:result callbackId:self.callbackId];
    }];
}

/* stop MobileAccessibility monitoring */
- (void)stop:(CDVInvokedUrlCommand*)command
{
    [self.commandDelegate runInBackground:^{
        // callback one last time to clear the callback function on JS side
        if (self.callbackId)
        {
            CDVPluginResult* result = [CDVPluginResult resultWithStatus:CDVCommandStatus_OK messageAsDictionary:[self getMobileAccessibilityStatus]];
            [result setKeepCallbackAsBool:NO];
            [self.commandDelegate sendPluginResult:result callbackId:self.callbackId];
        }
        self.callbackId = nil;
        [[NSNotificationCenter defaultCenter] removeObserver:self name:UIAccessibilityVoiceOverStatusChanged object:nil];
        [[NSNotificationCenter defaultCenter] removeObserver:self name:UIAccessibilityClosedCaptioningStatusDidChangeNotification object:nil];
        [[NSNotificationCenter defaultCenter] removeObserver:self name:UIAccessibilityGuidedAccessStatusDidChangeNotification object:nil];
        [[NSNotificationCenter defaultCenter] removeObserver:self name:UIAccessibilityInvertColorsStatusDidChangeNotification object:nil];
        [[NSNotificationCenter defaultCenter] removeObserver:self name:UIAccessibilityAnnouncementDidFinishNotification object:nil];
        [[NSNotificationCenter defaultCenter] removeObserver:self name:UIAccessibilityMonoAudioStatusDidChangeNotification object:nil];
    }];
}

@end