The permission of Facebook post is "Only me" using FBWebDialogs - ios

Question

I want to post text and link from iOS app to user timeline. I copy and paste FBWebDialogs example.
Problem 1:
The post appear in my timeline but the permission is "Only me", not friend or public.
Problem 2:
The result object (FBWebDialogResult) is nil. Log appear in my console.NSLog(#"User canceled story publishing.");
Problem 3:
The permission of preview box is "only me" even I set it to public
Attached setting of my Facebook page:
Here is my code:
[FBWebDialogs presentFeedDialogModallyWithSession:nil
parameters:params
handler:
^(FBWebDialogResult result, NSURL *resultURL, NSError *error) {
if (error) {
// Error launching the dialog or publishing a story.
NSLog(#"Error publishing story.");
} else {
if (result == FBWebDialogResultDialogNotCompleted) {
// User clicked the "x" icon
NSLog(#"User canceled story publishing.");
} else {
// Handle the publish feed callback
NSDictionary *urlParams = [self parseURLParams:[resultURL query]];
if (![urlParams valueForKey:#"post_id"]) {
NSLog(#"User canceled story publishing.");
} else {
NSString *msg = [NSString stringWithFormat:
#"Posted story, id: %#",
[urlParams valueForKey:#"post_id"]];
[[[UIAlertView alloc] initWithTitle:#"Result"
message:msg
delegate:nil
cancelButtonTitle:#"OK!"
otherButtonTitles:nil]
show];
}
}
}
}];
The setting page of my app is "only me" by default. I don't expect all my users change this setting here.

Answer 1

OMG. I stuggled for whole day but no progress. I found solution as soon as I ask question.
The problem is I copied inappropriate sample code. Ichanged to [FBSession openActiveSessionWithPublishPermissions] and problem solved.
Here is the login code I used. My post can be public now.
- (void)buttonRequestClickHandler:(id)sender {
// FBSample logic
// Check to see whether we have already opened a session.
if (FBSession.activeSession.isOpen) {
// login is integrated with the send button -- so if open, we send
// [self sendRequests];
NSLog(#"Login in facebook");
} else {
NSArray *permission = [NSArray arrayWithObjects:#"publish_actions", nil];
[FBSession openActiveSessionWithPublishPermissions:permission defaultAudience:FBSessionDefaultAudienceEveryone allowLoginUI:YES completionHandler:^(FBSession *session,
FBSessionState status,
NSError *error) {
// if login fails for any reason, we alert
if (error) {
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:#"Error"
message:error.localizedDescription
delegate:nil
cancelButtonTitle:#"OK"
otherButtonTitles:nil];
[alert show];
// if otherwise we check to see if the session is open, an alternative to
// to the FB_ISSESSIONOPENWITHSTATE helper-macro would be to check the isOpen
// property of the session object; the macros are useful, however, for more
// detailed state checking for FBSession objects
} else if (FB_ISSESSIONOPENWITHSTATE(status)) {
// send our requests if we successfully logged in
NSLog(#"Login in facebook"); }
}];
}