From the Facebook SDK sample code, when successfully post the open graph object to timeline, you have to click Show on Timeline in the Activity Log on Facebook website.
How to ignore these steps and explicit share your OG to timeline?
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Just add one more code to your FBOpenGraphAction Object:
id<FBOpenGraphAction> action = (id<FBOpenGraphAction>) [FBGraphObject graphObject];
[action setObject: @"true" forKey: @"fb:explicitly_shared"]; // This is the key point!
And you should enable the 'explicity shared' setting for the open graph action in the Facebook Developer App Dashboard in the website.
For more details, look at the Document about Explicit Sharing
You can use Scocial.framework for to directy post on facebook. It just use users built in facebook account associated with ios. And you will be able to post on timeline.
来源：https://stackoverflow.com/questions/17310892/ios-facebook-sdk-post-open-graph-and-show-on-timeline-without-clicking-activit