场景：
1.使用airdrop分享文件
2.使用其它app打开本app里面的文件，例如：图片，视频，pdf文件等等，
3.保存到本地文件夹
如果你有上面的任何一种需求那么看这篇文章就阔以了~。
本文按照以下三点讲解：
1.调起分享界面
2.如何可以把我们的app显示到分享界面
3.copy到我们app后如何处理
一.调起分享界面
这个比较简单，使用系统的UIDocumentInteractionController类，弹出后系统回自动识别能copy的app，回自己展示到弹出的面板上，系统自动处理了，很方便，不需要我们做多余的操作，比较简单，直接上代码：
NSString *imageZipPath = [[NSBundle mainBundle] pathForResource:@"image" ofType:@"zip"];
[self setupDocumentControllerWithURL:[NSURL fileURLWithPath:imageZipPath]];
BOOL ret = NO;
ret = [self.docInterCtrl
presentOpenInMenuFromRect:self.view.bounds
inView:self.view
animated:YES];
if (!ret)
{
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:Promt message:@"no app can open this file"preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:@"cancle" style:UIAlertActionStyleCancel handler:^(UIAlertAction *action) {
}];
[alertController addAction:cancelAction];
[self presentViewController:alertController animated:YES completion:nil];
}
- (void)setupDocumentControllerWithURL:(NSURL *)url
{
if (self.docInterCtrl == nil) {
self.docInterCtrl =
[UIDocumentInteractionController interactionControllerWithURL:url];
self.docInterCtrl.delegate = self;
} else {
self.docInterCtrl.URL = url;
}
}
注意事项：把UIDocumentInteractionController声明为一个强指针strong类型的实例，声明为局部的话回过早释放，会发生崩溃。
还可预览文件，这个需要事项相应的代理，比较简单，就不多说了。
二.如何可以把我们的app显示到分享界面
如果想我们的app可以打开别的app的文件，并展示到分享面板上，要配置一下info.plist文件,告诉系统哪些类型的文件需要使用UIDocumentInteractionController来打开。
总结一下：
<key>CFBundleDocumentTypes</key>
<array>
<dict>
<key>CFBundleTypeName</key>
<string>com.myapp.common-data</string>
<key>LSHandlerRank</key>
<string>Default</string>
<key>LSItemContentTypes</key>
<array>
<string>com.microsoft.powerpoint.ppt</string>
<string>public.item</string>
<string>com.microsoft.word.doc</string>
<string>com.adobe.pdf</string>
<string>com.microsoft.excel.xls</string>
<string>public.image</string>
<string>public.content</string>
<string>public.composite-content</string>
<string>public.archive</string>
<string>public.audio</string>
<string>public.movie</string>
<string>public.text</string>
<string>public.data</string>
</array>
</dict>
</array>
大概也就那么多，需要的直接粘贴就可以。
三.保存到本地文件夹
别的app的文件用我们的app打开，系统回将该文件copy到Documents/Inbox文件夹下，只需要对这个文件夹做处理及可以了。
我的做法是对Inbox文件夹做一个监听，文件夹有变动做某些操作即可。
监听文件夹使用的是苹果官方给出的类DirectoryWatcher
DirectoryWatcher.h
#import <Foundation/Foundation.h>
@class DirectoryWatcher;
@protocol DirectoryWatcherDelegate <NSObject>
@required
- (void)directoryDidChange:(DirectoryWatcher *)folderWatcher;
@end
@interface DirectoryWatcher : NSObject
{
id <DirectoryWatcherDelegate> __weak delegate;
int dirFD;
int kq;
CFFileDescriptorRef dirKQRef;
}
@property (nonatomic, weak) id <DirectoryWatcherDelegate> delegate;
+ (DirectoryWatcher *)watchFolderWithPath:(NSString *)watchPath delegate:(id<DirectoryWatcherDelegate>)watchDelegate;
- (void)invalidate;
@end
DirectoryWatcher.m
#import "DirectoryWatcher.h"
#include <sys/types.h>
#include <sys/event.h>
#include <sys/time.h>
#include <fcntl.h>
#include <unistd.h>
#import <CoreFoundation/CoreFoundation.h>
@interface DirectoryWatcher (DirectoryWatcherPrivate)
- (BOOL)startMonitoringDirectory:(NSString *)dirPath;
- (void)kqueueFired;
@end
@implementation DirectoryWatcher
@synthesize delegate;
- (instancetype)init
{
self = [super init];
delegate = NULL;
dirFD = -1;
kq = -1;
dirKQRef = NULL;
return self;
}
- (void)dealloc
{
[self invalidate];
}
+ (DirectoryWatcher *)watchFolderWithPath:(NSString *)watchPath delegate:(id)watchDelegate
{
DirectoryWatcher *retVal = NULL;
if ((watchDelegate != NULL) && (watchPath != NULL))
{
DirectoryWatcher *tempManager = [[DirectoryWatcher alloc] init];
tempManager.delegate = watchDelegate;
if ([tempManager startMonitoringDirectory: watchPath])
{
// Everything appears to be in order, so return the DirectoryWatcher.
// Otherwise we'll fall through and return NULL.
retVal = tempManager;
}
}
return retVal;
}
- (void)invalidate
{
if (dirKQRef != NULL)
{
CFFileDescriptorInvalidate(dirKQRef);
CFRelease(dirKQRef);
dirKQRef = NULL;
// We don't need to close the kq, CFFileDescriptorInvalidate closed it instead.
// Change the value so no one thinks it's still live.
kq = -1;
}
if(dirFD != -1)
{
close(dirFD);
dirFD = -1;
}
}
@end
#pragma mark -
@implementation DirectoryWatcher (DirectoryWatcherPrivate)
- (void)kqueueFired
{
assert(kq >= 0);
struct kevent event;
struct timespec timeout = {0, 0};
int eventCount;
eventCount = kevent(kq, NULL, 0, &event, 1, &timeout);
assert((eventCount >= 0) && (eventCount < 2));
// call our delegate of the directory change
[delegate directoryDidChange:self];
CFFileDescriptorEnableCallBacks(dirKQRef, kCFFileDescriptorReadCallBack);
}
static void KQCallback(CFFileDescriptorRef kqRef, CFOptionFlags callBackTypes, void *info)
{
DirectoryWatcher *obj;
obj = (__bridge DirectoryWatcher *)info;
assert([obj isKindOfClass:[DirectoryWatcher class]]);
assert(kqRef == obj->dirKQRef);
assert(callBackTypes == kCFFileDescriptorReadCallBack);
[obj kqueueFired];
}
- (BOOL)startMonitoringDirectory:(NSString *)dirPath
{
// Double initializing is not going to work...
if ((dirKQRef == NULL) && (dirFD == -1) && (kq == -1))
{
// Open the directory we're going to watch
dirFD = open([dirPath fileSystemRepresentation], O_EVTONLY);
if (dirFD >= 0)
{
// Create a kqueue for our event messages...
kq = kqueue();
if (kq >= 0)
{
struct kevent eventToAdd;
eventToAdd.ident = dirFD;
eventToAdd.filter = EVFILT_VNODE;
eventToAdd.flags = EV_ADD | EV_CLEAR;
eventToAdd.fflags = NOTE_WRITE;
eventToAdd.data = 0;
eventToAdd.udata = NULL;
int errNum = kevent(kq, &eventToAdd, 1, NULL, 0, NULL);
if (errNum == 0)
{
CFFileDescriptorContext context = { 0, (__bridge void *)(self), NULL, NULL, NULL };
CFRunLoopSourceRef rls;
// Passing true in the third argument so CFFileDescriptorInvalidate will close kq.
dirKQRef = CFFileDescriptorCreate(NULL, kq, true, KQCallback, &context);
if (dirKQRef != NULL)
{
rls = CFFileDescriptorCreateRunLoopSource(NULL, dirKQRef, 0);
if (rls != NULL)
{
CFRunLoopAddSource(CFRunLoopGetCurrent(), rls, kCFRunLoopDefaultMode);
CFRelease(rls);
CFFileDescriptorEnableCallBacks(dirKQRef, kCFFileDescriptorReadCallBack);
// If everything worked, return early and bypass shutting things down
return YES;
}
// Couldn't create a runloop source, invalidate and release the CFFileDescriptorRef
CFFileDescriptorInvalidate(dirKQRef);
CFRelease(dirKQRef);
dirKQRef = NULL;
}
}
// kq is active, but something failed, close the handle...
close(kq);
kq = -1;
}
// file handle is open, but something failed, close the handle...
close(dirFD);
dirFD = -1;
}
}
return NO;
}
@end
将这两个文件夹导入使用既可。
eg:
#import "DirVC.h"
#import "DirectoryWatcher.h"
@interface DirVC ()<DirectoryWatcherDelegate>
@property (nonatomic, strong) DirectoryWatcher *indoxWatcher;
@end
@implementation DirVC
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view from its nib.
self.indoxWatcher = [DirectoryWatcher watchFolderWithPath:[NSHomeDirectory() stringByAppendingPathComponent:[NSString stringWithFormat:@"Documents/Inbox"]] delegate:self];
}
#pragma mark - 文件夹变动监听代理
- (void)directoryDidChange:(DirectoryWatcher *)folderWatcher
{
}
@end
这样就能监听相应文件夹的变化了，不过Inbox文件夹操作文件的时候有点问题，建议将文件copy到自己建的文件夹做相应的操作。
如此就可以了，如果有更好的方法，欢迎私信交流~。
