# NgKeyboardTracker

Objective-c library for tracking keyboard in iOS apps.

![](https://github.com/meiwin/ngkeyboardtracker/blob/master/ngkeyboardtracker.gif)

## Adding to your project

If you are using CocoaPods, add to your Podfile:

```ruby
pod 'NgKeyboardTracker'
```

To manually add to your projects:

1. Add files in `NgKeyboardTracker` folder to your project.
2. Add these frameworks to your project: `UIKit`.

## Features

`NgKeyboardTracker` encapsulates keyboard tracking for iOS apps.
It provides convenience to query keyboard's properties anywhere in your application.

You can also use `NgKeyboardTracker` to implement iMessage's text input behavior on iOS 7 (`UIScrollViewKeyboardDismissModeInteractive` + persistent `inputAccessoryView`) using `NgPseudoInputAccessoryViewCoordinator`.

## Usage

### Start and stop keyboard tracking

In your application delegate:

```objective-c
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
  [[NgKeyboardTracker sharedTracker] start]; // start tracking
  return YES;
}

- (void)applicationWillTerminate:(UIApplication *)application {
  // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
  [[NgKeyboardTracker sharedTracker] stop]; // stop tracking
}
```

### Responding to keyboard updates

1. Implement `NgKeyboardTrackerDelegate` protocol.
2. Register as delegate by calling `-addDelegate:` method
3. Make sure to call `-removeDelegate:` to stop receiving keyboard updates

Keyboard tracker's properties:

- `appearanceState` : current appearance state
- `beginFrame` : last known begin frame
- `endFrame`: last known frame
- `currentFrame`: last known current keyboard's frame
- `animationDuration`: last known animation duration
- `animationCurve`: last known animation curve
- `animationOptions` : derived from `animationCurve` for convenience

P.S. keyboard's `frame.size.height` system's keyboard height plus `inputAccessoryView` height.

### Pseudo input accessory view coordinator

`NgPseudoInputAccessoryViewCoordinator` is `NgKeyboardTracker` extension that makes it easier to implement iMessage's text input behavior in iOS 7 with `UIScrollViewKeyboardDismissModeInteractive` and persistent `inputAccessoryView`.

The view controller:

1. Override `loadView` to set custom UIView implementation.
2. Make sure to call the custom view's `becomeFirstResponder`.

The custom view:

1. Create `NgPseudoInputAccessoryViewCoordinator` by calling `-createPseudoInputAccessoryViewCoordinator`.
2. Overrides `-canBecomeFirstResponder`, returns `YES`.
3. Overrides `-inputAccessoryView`, returns coordinator's `pseudoInputAccessoryView`.
4. Set `UIScrollView`'s keyboard dismiss mode to `UIScrollViewKeyboardDismissModeInteractive`.
5. Set desired height of input accessory view with `-setPseudoInputAccessoryViewHeight:`.
6. Layout keyboard's bar accordingly using information from `NgKeyboardTracker` in `layoutSubviews`.

P.S. See demo application for example.