如何在 Objective-C 中将照片分享到 Facebook？

Question

我想在我的自定义按钮点击后分享照片，我可以分享链接和消息，但在分享照片时却无法做到。

我正在使用最新的 Facebook SDK 框架 (4.15.1)。

这是我在按钮点击中的代码。

 - (IBAction)btnsharecustom:(id)sender {

//Get aws s3 Image.
NSString* strS3ImageURL = @"https://TEST_IMAGE_URL/1473497380077.jpg";

//Convert to URL.
NSURL* url1 = [NSURL URLWithString:strS3ImageURL];

//Convert it into data.
NSData* data = [NSData dataWithContentsOfURL:url1];

//Convert it to image.
UIImage* image = [UIImage imageWithData:data];    

FBSDKSharePhoto *photo = [[FBSDKSharePhoto alloc]init];

photo.image = image;
photo.caption = @"Test Caption";
photo.userGenerated = YES;

FBSDKSharePhotoContent *content = [[FBSDKSharePhotoContent alloc] init];
content.photos = @[photo];
}

我将此代码包含在应用程序委托中。

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// Override point for customization after application launch.

[[FBSDKApplicationDelegate sharedInstance] application:application
                         didFinishLaunchingWithOptions:launchOptions];    

return YES;
}

//FaceBook URLs.
- (BOOL)application:(UIApplication *)application openURL:(NSURL *)url
 sourceApplication:(NSString *)sourceApplication annotation:(id)annotation {

BOOL handled = [[FBSDKApplicationDelegate sharedInstance] application:application
                                                              openURL:url
                                                    sourceApplication:sourceApplication
                                                           annotation:annotation
                ];
// Add any custom logic here.
return handled;
}

在 info.plist 中也包含此代码

    <dict>
        <key>CFBundleURLSchemes</key>
        <array>
            <string>fb15771408xxx409xx</string>
        </array>
    </dict>

<key>FacebookAppID</key>
<string>15771408xxx409xx</string>
<key>FacebookDisplayName</key>
<string>Cedar iOS</string>
<key>LSApplicationQueriesSchemes</key>
<array>
    <string>fbapi</string>
    <string>fb-messenger-api</string>
    <string>fbauth2</string>
    <string>fbshareextension</string>
    <string>fbapi20130214</string>
    <string>fbapi20130410</string>
    <string>fbapi20130702</string>
    <string>fbapi20131010</string>
    <string>fbapi20131219</string>
    <string>fbapi20140410</string>
    <string>fbapi20140116</string>
    <string>fbapi20150313</string>
    <string>fbapi20150629</string>
    <string>fbapi20160328</string>
    <string>fbauth</string>
    <string>fb-messenger-api20140430</string>
</array>

当我点击我的自定义按钮 Facebook 应用程序或 safari 浏览器未启动时，谁能告诉我这里缺少什么？

Answer 1

您应该在对内容进行建模后自己呈现对话框。

添加这个

[FBSDKShareDialog showFromViewController:self
                          withContent:content
                             delegate:nil];

到您的 - (IBAction)btnsharecustom:(id)sender 方法结束。

---

注意：下载图片需要时间，因为它使用同步请求。

//Convert it into data.
NSData* data = [NSData dataWithContentsOfURL:url1];

在此处阅读文档https://developer.apple.com/reference/foundation/nsdata/1547245-datawithcontentsofurl

不要使用这种同步方法来请求基于网络的 URL。对于基于网络的 URL，此方法会在慢速网络上阻塞当前线程数十秒，导致用户体验不佳，并且在 iOS 中可能会导致您的应用被终止。

解决此问题的方法是在用户点击按钮之前异步下载您的图片（如果要上传的图片是可预测的）。通常你可以在viewDidLoad 方法中做到这一点。试试这个https://github.com/rs/SDWebImage 库来简化异步请求图像。

Answer 2

试试这个代码。

- (IBAction)btnsharecustom:(id)sender {

    //Get aws s3 Image.
    NSString* strS3ImageURL = @"https://placeholdit.imgix.net/~text?txtsize=15&txt=image1&w=120&h=120";

    //Convert to URL.
    NSURL* url1 = [NSURL URLWithString:strS3ImageURL];

    //Convert it into data.
    NSData* data = [NSData dataWithContentsOfURL:url1];

    //Convert it to image.
    UIImage* image = [UIImage imageWithData:data];

    FBSDKSharePhoto *photo = [[FBSDKSharePhoto alloc]init];

    photo.image = image;
    photo.caption = @"Test Caption";
    photo.userGenerated = YES;

    FBSDKSharePhotoContent *content = [[FBSDKSharePhotoContent alloc] init];
    content.photos = @[photo];
    [FBSDKShareAPI shareWithContent:content delegate:self];
;
}
- (void)sharer:(id<FBSDKSharing>)sharer didCompleteWithResults:(NSDictionary *)results{

}

Answer 3

进口

// 委托 FBSDKSharingDelegate

-(void)shareImageWithFacebook:(UIImage *)image { if(![[UIApplication sharedApplication] canOpenURL:[NSURL URLWithString:@"fb://"]]) { //您的设备没有 Facebook 应用。 返回; }

FBSDKSharePhoto *photo = [FBSDKSharePhoto alloc];
photo.image = _imageSaved;
[photo setUserGenerated:YES];
photo.caption = AppName;
FBSDKSharePhotoContent *photoContent = [FBSDKSharePhotoContent alloc];
photoContent.photos = @[photo];

FBSDKShareDialog *dialog = [[FBSDKShareDialog alloc] init];
dialog.fromViewController = self;
dialog.delegate = self;
dialog.shareContent = photoContent;
[dialog show];

}

pragma mark- FBShareKit 委托

• (void)sharer:(id)sharer didCompleteWithResults:(NSDictionary *)results { }
• (void)sharer:(id)sharer didFailWithError:(NSError *)error { }
• (void)sharerDidCancel:(id)sharer { }