ios开发之获取应用程序列表

    有的时候，我们需要在实现应用间调用功能，系统自带的方式固然方便。

但是，如果我们能在调用前先获取系统的应用列表岂不更爽快。因此，今天

我们就来实现获取应用列表的功能。直接上代码！

+ (BOOL) APCheckIfAppInstalled:(NSString *)bundleIdentifier

{

    staticNSString *const cacheFileName =@"com.apple.mobile.installation.plist";

    NSString *relativeCachePath = [[@"Library"stringByAppendingPathComponent:@"Caches"]stringByAppendingPathComponent: cacheFileName];

   NSDictionary *cacheDict =nil;

   NSString *path =nil;

    // Loop through all possible paths the cache could be in

   for (short i =0;1; i++)

    {

        

       switch (i) {

            case0:// Jailbroken apps will find the cache here; their home directory is /var/mobile

                path = [NSHomeDirectory()stringByAppendingPathComponent: relativeCachePath];

               break;

            case1:// App Store apps and Simulator will find the cache here; home (/var/mobile/) is 2 directories above sandbox folder

                path = [[NSHomeDirectory()stringByAppendingPathComponent:@"../.."]stringByAppendingPathComponent: relativeCachePath];

               break;

            case2:// If the app is anywhere else, default to hardcoded /var/mobile/

                path = [@"/var/mobile"stringByAppendingPathComponent: relativeCachePath];

               break;

            default:// Cache not found (loop not broken)

               returnNO;

           break; }

        

       BOOL isDir =NO;

       if ([[NSFileManagerdefaultManager]fileExistsAtPath: pathisDirectory: &isDir] && !isDir)// Ensure that file exists

            cacheDict = [NSDictionarydictionaryWithContentsOfFile: path];

        

        if (cacheDict)//If cache is loaded, then break the loop. If the loop is not "broken," it will return NO later (default: case)

           break;

    }

    

    NSDictionary *system = [cacheDictobjectForKey:@"System"];// First check all system (jailbroken) apps

   if ([systemobjectForKey: bundleIdentifier])returnYES;

    NSDictionary *user = [cacheDictobjectForKey:@"User"];// Then all the user (App Store /var/mobile/Applications) apps

   if ([userobjectForKey: bundleIdentifier])returnYES;

    

    // If nothing returned YES already, we'll return NO now

    return NO;

}