SHScroller

Author

Sho Miyamoto

Description

Have you ever thought that you are reluctant to reach out your thumb to change tabs or navigations etc?

If so, your users think alike.

This totally simple library provides another secret scroll bar to do it without stretching fingers. With SHScroller, you can change tabs by swiping up or down the right edge of the screen.

Concretely, this is an invisible view (UIControl) on the far right edge. When users scroll or swipe along the right edge, you can implement a function triggered by users’ swiping.

For instance, UITabBarController. As you can see the demo video below, when users swipe down along an invisible scroll bar on the right edge, the displayed tab is changed to the following tab. In swiping upward, the previous tab is coming up.

On the Github, there is a demo project, in which a UITabBarController is used as a sample. Check it.

Requirements

• Swift 2.2
• Xcode 7.3

Installation

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

pod "SHScroller"

Usage

Initializing

At first initialize SHScroller.

In your func viewDidLoad() of ViewController, add some lines below.

let scroller = SHScroller(superView: self.view)

self.view.addSubview(scroller)

Setting a target function triggered by scrolling

Also in func viewDidLoad(), add this line.

scroller.addTarget(self, action: #selector(ViewController.changed), forControlEvents: .ValueChanged)

And replace the content of #selector() with your function.

Triggered function

Make associated function designated by .addTarget().

func changed(scroller: SHScroller) {
    // e.g.
    self.selectedIndex += scroller.delta
}

You can access only this property named delta, which can only be read. Delta takes either 1 (swiping downward) or -1 (upward).

The setup is finished.

Customizing

In initializing, you can also designate sensitivity number and range like this.

• sensitivity: Int represents the sensitivity of swiping, which is actually how many hit fields will be divided into. The default value is 10.
• range: CGFloat is the horizontally range of hit areas. In the respect of the balance between the performance and less influence to super view, I recommend you keep the default value 15.0 or so.

let scroller = SHScroller(superView: self.view, sensitivity: 15, range: 20.0)

self.view.addSubview(scroller)

And… just in case of implementation for the left-handed.

let scroller = SHScroller(superView: self.view, is_left: true)

self.view.addSubview(scroller)

Comments

This is the first time to make OSS, and I started Python this April as the first programming language. Though this is so simple library, it was very good experience for me. Please give me any hints, advices, corrections about anything, thank you.

License

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