GSKStretchyHeaderView

[](https://travis-ci.org/Jose Alcalá Correa/GSKStretchyHeaderView)

GSKStretchyHeaderView is an implementation of the stretchy header paradigm as seen on the Twitter app or the Spotify app. It's designed in order to accomplish the following requirements:

• Compatibility with UITableView and UICollectionView
• Provide support for frame layout, auto layout and Interface Builder .xib files
• No need to subclass a custom view controller or to use a custom UICollectionViewLayout
• Simple usage: just implement your own subclass and add it to your UIScrollView subclass

Usage

To add a stretchy header to your table or collection view, you just have to do this:

- (void)viewDidLoad {
    [super viewDidLoad];
    CGSize headerSize = CGSizeMake(self.tableView.frame.size.width, 200); // 200 will be the default height
    self.stretchyHeader = [[GSKStretchyHeaderViewSubclass alloc] initWithFrame:CGRectMake(0, 0, headerSize.width, headerSize.height)];
    self.stretchyHeader.delegate = self; // this is completely optional
    [self.tableView addSubview:self.stretchyHeader];
}

or

- (void)viewDidLoad {
    [super viewDidLoad];
    NSArray<UIView *> *nibViews = [[NSBundle mainBundle] loadNibNamed:@"GSKTabsStretchyHeaderView"
                                                                owner:self
                                                              options:nil];
    self.stretchyHeaderView = nibViews.firstObject;
    [self.tableView addSubview:self.stretchyHeaderView];
}

Creating your stretchy header

There are two ways to create your own stretchy header:

• Create a stretchy header subclass and add subviews to its contentView. You can layout its subviews with manual layouting (by using frames) or with Auto Layout.
• Create an Interface Builder file and map it to your GSKStretchyHeaderView subclass. Subviews added to the stretchy header will be automatically moved to the content view, keeping their constraints. Remember to set the properties maximumContentHeight and minimumContentHeight in the attributes inspector (fourth tab on the right panel in Interface Builder).

To modify the behaviour and layout of your stretchy header, just override the method -didChangeStretchFactor: in your subclass, where you can adjust it by using the stretchFactor. To get a more detailed description of the properties, please have a look at the source code. There are also a few usage examples in the example project. You can also take them as a reference for your own stretchy headers.

Example project

To run the example project, clone the repo, and run pod install from the Example directory first.

Installation

GSKStretchyHeaderView is available through CocoaPods. To install it, simply add the following line to your Podfile:

pod "GSKStretchyHeaderView"

Author

Jose Alcalá Correa, jose.alcala.correa@gmail.com

License

GSKStretchyHeaderView is available under the MIT license. See the LICENSE file for more info.