I coding a ios app, it have muti button share by openURL. After fisrt button press, it open safari for share, and when I back to my app, all button is not work. (only ios 7.1, but ios 8 worked fine)

This is my code:

-(IBAction)btnFacebook_TouchUpInSide:(id)sender {
    NSLog(@"Touch FaceBook");
    NSString *shareUrl = @"some url";
    NSString *shareText = @"some text";
    NSString *shareDescription = @"some text";
    NSString *sharePictureUrl = @"some text";
    NSString *sharingURL = [self encodeURL:[NSString stringWithFormat:
 @"https://www.facebook.com/dialog/feed?
 app_id=388711667988471&display=page&caption=
%@&description=%@&picture=%@&link=%@&
 redirect_uri=%@", shareText, shareDescription, 
 sharePictureUrl, shareUrl, shareUrl]];
    if([[UIApplication sharedApplication] canOpenURL:[NSURL URLWithString:
 sharingURL]]) {
        [[UIApplication sharedApplication] openURL:[NSURL URLWithString:
 sharingURL]];
    }
}
- (IBAction)btnTwitter_TouchUpInSide:(id)sender {
    NSLog(@"Touch Twitter");
    NSString *shareUrl = @"some url";
    NSString *shareText = @"some text";
    NSString *sharingURL = [self encodeURL:[NSString stringWithFormat:
 @"twitter://post?message=%@", [self encodeURL:
 [NSString stringWithFormat:@"%@ %@", shareUrl, shareText]]]];
    if([[UIApplication sharedApplication] canOpenURL:[NSURL URLWithString:
 sharingURL]]) {
        [[UIApplication sharedApplication] openURL:[NSURL URLWithString:
 sharingURL]];
    }  else {
        NSLog(@"Open web to share twitter!");
        sharingURL = [NSString stringWithFormat:@"https://twitter.com/
intent/tweet?url=%@&text=%@&count=none/",
 [self encodeURL:shareUrl],[self encodeURL:shareText]];
        if([[UIApplication sharedApplication] canOpenURL:[NSURL URLWithString:
 sharingURL]]) {
            [[UIApplication sharedApplication] openURL:[NSURL URLWithString:
 sharingURL]];
        }
    }
}
- (IBAction)btnPinterest_TouchUpInSide:(id)sender {
    NSLog(@"Touch Pinterest");
    NSString *shareUrl = @"some url";
    NSString *shareText = @"some text";
    NSString *shareMedia = @"some text";
    NSString *sharingURL = [self encodeURL:[NSString stringWithFormat:
 @"pinit12://pinterest.com/pin/create/link/?
url=%@&media=%@&description=%@", shareUrl, shareMedia, shareText]];
    if([[UIApplication sharedApplication] canOpenURL:[NSURL URLWithString:
 sharingURL]]){
        [[UIApplication sharedApplication] openURL:[NSURL URLWithString:
 sharingURL]];
    } else {
        NSLog(@"Open web to share Pinterest!");
        sharingURL = [self encodeURL:[NSString stringWithFormat:
 @"https://www.pinterest.com/pin/create/link/?url=%
 @&media=%@&description=%@", shareUrl, shareMedia, shareText]];
        if([[UIApplication sharedApplication] canOpenURL:[NSURL URLWithString:
 sharingURL]]) {
            [[UIApplication sharedApplication] openURL:[NSURL URLWithString:
 sharingURL]];
        }
    }
}
- (IBAction)btnLinkedIn_TouchUpInSide:(id)sender {
    NSLog(@"Touch LinkedIn");
    NSString *shareUrl = @"some url";
    NSString *shareTitle = @"some text";
    NSString *shareSummary = @"some text";
    NSString *shareSource = @"some text";
    NSString *sharingURL = [NSString stringWithFormat:
 @"https://www.linkedin.com/shareArticle?
mini=true&url=%@&title=%@&summary=%
 @&source=%@",[self encodeURL:shareUrl],
 [self encodeURL:shareTitle],[self encodeURL:
 shareSummary],[self encodeURL:shareSource]];
    if([[UIApplication sharedApplication] canOpenURL:[NSURL URLWithString:
 sharingURL]]){
        [[UIApplication sharedApplication] openURL:[NSURL URLWithString:
 sharingURL]];
    }
}

Thanks in advance...