检查互联网连接iOS 5

时间:2012-02-21 22:27:16

标签: iphone ios5 automatic-ref-counting reachability connectivity

我正在制作一个需要互联网连接的应用。 我正在寻找检查互联网连接并返回警报视图的最佳方法。 我已经开始蠢蠢欲动,只能在iOS 4中找到上述方法,但我正在制作的应用程序是在iOS 5中。

我已经看过了apple Reachability示例代码,但是当我尝试实现时,这只会让我的代码错误变得疯狂(因为它是为iOS 4构建的)。

编辑: 当我将reachability.h文件导入到我的项目中时,我得到10个错误(其中6个我可以简单地修复)和4个我不知道该怎么做。

2 个答案:

答案 0 :(得分:8)

您可以通过设置-fno-objc-arc编译器标志,从该文件中简单地排除ARC。像这样:

enter image description here

答案 1 :(得分:7)

我已经改编了Apple的Reachability课程用于ARC,试试吧。

/*

 File: Reachability.m
 Abstract: Basic demonstration of how to use the SystemConfiguration Reachablity APIs.

 Version: 2.2

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 constitutes acceptance of these terms.  If you do not agree with these terms,
 please do not use, install, modify or redistribute this Apple software.

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 to these terms, Apple grants you a personal, non-exclusive license, under
 Apple's copyrights in this original Apple software (the "Apple Software"), to
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 modifications, in source and/or binary forms; provided that if you redistribute
 the Apple Software in its entirety and without modifications, you must retain
 this notice and the following text and disclaimers in all such redistributions
 of the Apple Software.
 Neither the name, trademarks, service marks or logos of Apple Inc. may be used
 to endorse or promote products derived from the Apple Software without specific
 prior written permission from Apple.  Except as expressly stated in this notice,
 no other rights or licenses, express or implied, are granted by Apple herein,
 including but not limited to any patent rights that may be infringed by your
 derivative works or by other works in which the Apple Software may be
 incorporated.

 The Apple Software is provided by Apple on an "AS IS" basis.  APPLE MAKES NO
 WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED
 WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND OPERATION ALONE OR IN
 COMBINATION WITH YOUR PRODUCTS.

 IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR
 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, MODIFICATION AND/OR
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 APPLE HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 Copyright (C) 2010 Apple Inc. All Rights Reserved.

 */

#import <sys/socket.h>
#import <netinet/in.h>
#import <netinet6/in6.h>
#import <arpa/inet.h>
#import <ifaddrs.h>
#import <netdb.h>

#import <CoreFoundation/CoreFoundation.h>

#import "Reachability.h"

#define kShouldPrintReachabilityFlags 0

static void PrintReachabilityFlags(SCNetworkReachabilityFlags    flags, const char* comment)
{
#if kShouldPrintReachabilityFlags

    NSLog(@"Reachability Flag Status: %c%c %c%c%c%c%c%c%c %s\n",
          (flags & kSCNetworkReachabilityFlagsIsWWAN)               ? 'W' : '-',
          (flags & kSCNetworkReachabilityFlagsReachable)            ? 'R' : '-',

          (flags & kSCNetworkReachabilityFlagsTransientConnection)  ? 't' : '-',
          (flags & kSCNetworkReachabilityFlagsConnectionRequired)   ? 'c' : '-',
          (flags & kSCNetworkReachabilityFlagsConnectionOnTraffic)  ? 'C' : '-',
          (flags & kSCNetworkReachabilityFlagsInterventionRequired) ? 'i' : '-',
          (flags & kSCNetworkReachabilityFlagsConnectionOnDemand)   ? 'D' : '-',
          (flags & kSCNetworkReachabilityFlagsIsLocalAddress)       ? 'l' : '-',
          (flags & kSCNetworkReachabilityFlagsIsDirect)             ? 'd' : '-',
          comment
          );
#endif
}


@implementation Reachability
static void ReachabilityCallback(SCNetworkReachabilityRef target, SCNetworkReachabilityFlags flags, void* info)
{
#pragma unused (target, flags)
    NSCAssert(info != NULL, @"info was NULL in ReachabilityCallback");
    NSCAssert([(NSObject*) objc_unretainedObject(info) isKindOfClass: [Reachability class]], @"info was wrong class in ReachabilityCallback");

    //We're on the main RunLoop, so an NSAutoreleasePool is not necessary, but is added defensively
    // in case someon uses the Reachablity object in a different thread.
    @autoreleasepool {    
        Reachability* noteObject = (Reachability*) objc_unretainedObject(info);
        // Post a notification to notify the client that the network reachability changed.
        [[NSNotificationCenter defaultCenter] postNotificationName: kReachabilityChangedNotification object: noteObject];
    }
}

- (BOOL) startNotifier
{
    BOOL retVal = NO;
    const void *pointer = objc_unretainedPointer(self);
    SCNetworkReachabilityContext context = {0, (void *) pointer, NULL, NULL, NULL};
    if(SCNetworkReachabilitySetCallback(reachabilityRef, ReachabilityCallback, &context))
    {
        if(SCNetworkReachabilityScheduleWithRunLoop(reachabilityRef, CFRunLoopGetCurrent(), kCFRunLoopDefaultMode))
        {
            retVal = YES;
        }
    }
    return retVal;
}

- (void) stopNotifier
{
    if(reachabilityRef!= NULL)
    {
        SCNetworkReachabilityUnscheduleFromRunLoop(reachabilityRef, CFRunLoopGetCurrent(), kCFRunLoopDefaultMode);
    }
}

- (void) dealloc
{
    [self stopNotifier];
    if(reachabilityRef!= NULL)
    {
        CFRelease(reachabilityRef);
    }
}

+ (Reachability*) reachabilityWithHostName: (NSString*) hostName;
{
    Reachability* retVal = NULL;
    SCNetworkReachabilityRef reachability = SCNetworkReachabilityCreateWithName(NULL, [hostName UTF8String]);
    if(reachability!= NULL)
    {
        retVal= [[self alloc] init];
        if(retVal!= NULL)
        {
            retVal->reachabilityRef = reachability;
            retVal->localWiFiRef = NO;
        }
    }
    return retVal;
}

+ (Reachability*) reachabilityWithAddress: (const struct sockaddr_in*) hostAddress;
{
    SCNetworkReachabilityRef reachability = SCNetworkReachabilityCreateWithAddress(kCFAllocatorDefault, (const struct sockaddr*)hostAddress);
    Reachability* retVal = NULL;
    if(reachability!= NULL)
    {
        retVal= [[self alloc] init];
        if(retVal!= NULL)
        {
            retVal->reachabilityRef = reachability;
            retVal->localWiFiRef = NO;
        }
    }
    return retVal;
}

+ (Reachability*) reachabilityForInternetConnection;
{
    struct sockaddr_in zeroAddress;
    bzero(&zeroAddress, sizeof(zeroAddress));
    zeroAddress.sin_len = sizeof(zeroAddress);
    zeroAddress.sin_family = AF_INET;
    return [self reachabilityWithAddress: &zeroAddress];
}

+ (Reachability*) reachabilityForLocalWiFi;
{
    struct sockaddr_in localWifiAddress;
    bzero(&localWifiAddress, sizeof(localWifiAddress));
    localWifiAddress.sin_len = sizeof(localWifiAddress);
    localWifiAddress.sin_family = AF_INET;
    // IN_LINKLOCALNETNUM is defined in <netinet/in.h> as 169.254.0.0
    localWifiAddress.sin_addr.s_addr = htonl(IN_LINKLOCALNETNUM);
    Reachability* retVal = [self reachabilityWithAddress: &localWifiAddress];
    if(retVal!= NULL)
    {
        retVal->localWiFiRef = YES;
    }
    return retVal;
}

#pragma mark Network Flag Handling

- (NetworkStatus) localWiFiStatusForFlags: (SCNetworkReachabilityFlags) flags
{
    PrintReachabilityFlags(flags, "localWiFiStatusForFlags");

    BOOL retVal = NotReachable;
    if((flags & kSCNetworkReachabilityFlagsReachable) && (flags & kSCNetworkReachabilityFlagsIsDirect))
    {
        retVal = ReachableViaWiFi;  
    }
    return retVal;
}

- (NetworkStatus) networkStatusForFlags: (SCNetworkReachabilityFlags) flags
{
    PrintReachabilityFlags(flags, "networkStatusForFlags");
    if ((flags & kSCNetworkReachabilityFlagsReachable) == 0)
    {
        // if target host is not reachable
        return NotReachable;
    }

    BOOL retVal = NotReachable;

    if ((flags & kSCNetworkReachabilityFlagsConnectionRequired) == 0)
    {
        // if target host is reachable and no connection is required
        //  then we'll assume (for now) that your on Wi-Fi
        retVal = ReachableViaWiFi;
    }


    if ((((flags & kSCNetworkReachabilityFlagsConnectionOnDemand ) != 0) ||
         (flags & kSCNetworkReachabilityFlagsConnectionOnTraffic) != 0))
    {
        // ... and the connection is on-demand (or on-traffic) if the
        //     calling application is using the CFSocketStream or higher APIs

        if ((flags & kSCNetworkReachabilityFlagsInterventionRequired) == 0)
        {
            // ... and no [user] intervention is needed
            retVal = ReachableViaWiFi;
        }
    }

    if ((flags & kSCNetworkReachabilityFlagsIsWWAN) == kSCNetworkReachabilityFlagsIsWWAN)
    {
        // ... but WWAN connections are OK if the calling application
        //     is using the CFNetwork (CFSocketStream?) APIs.
        retVal = ReachableViaWWAN;
    }
    return retVal;
}

- (BOOL) connectionRequired;
{
    NSAssert(reachabilityRef != NULL, @"connectionRequired called with NULL reachabilityRef");
    SCNetworkReachabilityFlags flags;
    if (SCNetworkReachabilityGetFlags(reachabilityRef, &flags))
    {
        return (flags & kSCNetworkReachabilityFlagsConnectionRequired);
    }
    return NO;
}

- (NetworkStatus) currentReachabilityStatus
{
    NSAssert(reachabilityRef != NULL, @"currentNetworkStatus called with NULL reachabilityRef");
    NetworkStatus retVal = NotReachable;
    SCNetworkReachabilityFlags flags;
    if (SCNetworkReachabilityGetFlags(reachabilityRef, &flags))
    {
        if(localWiFiRef)
        {
            retVal = [self localWiFiStatusForFlags: flags];
        }
        else
        {
            retVal = [self networkStatusForFlags: flags];
        }
    }
    return retVal;
}
@end