ember-key-responder

A component-oriented approach to keyboard shortcuts for Ember, inspired by Cocoa's KeyResponder.

ember-key-responder will delegate keyEvents to the current keyResponder. Typically a keyResponder is a view, or a component. In complex applications, various keyResponders enter and leave the system. Since only 1 keyResponder can be active at any given point in time, a stack of them is maintained. The top of the stack is considered the current keyResponder.

This allows for modals or other UI components to naturally become the default responder. As they enter they are pushed onto the stack. When they resign themselves they are dropped from the stack.

Example

Given the following components component-a and component-b

// component-a.js | component-b.js
export default Ember.Component.extend({
  acceptsKeyResponder: true,
  didInsertElement: function() {
    this.becomeKeyResponder(false /* true: replace | false: pushOnToStack*/);
    this._super.apply(this, arguments);
  },

  willDestroyElement: function() {
    this.resignKeyResponder();
    this._super.apply(this, arguments);
  },

  moveUp: function() {
    // do something
  }
});

the template layout of

{{#component-a}
  {{#if showB}}
    {{#component-b}
    {{/component-b}
  {{/if}}
{{/component-a}

and showB is true

the stack of key responders is

component-b // <= current keyResponder
component-a

Key events captured will be delegated to component-b.

If showB becomes false then component-b will be removed and the stack becomes

component-a // <- current keyResponder

At this point in time key events will be delegated to component-a.

Further Usage

ember install:npm ember-key-responder

// app/views/key-reponder-base.js

export default Ember.View.extend({
  acceptsKeyResponder: true,
  didInsertElement: function() {
    this.becomeKeyResponder(false /* true: replace | false: pushOnToStack*/);
    this._super();
  },

  willDestroyElement: function() {
    this.resignKeyResponder();
    this._super();
  }
});

Events:

export var KEY_EVENTS = {
  8: 'deleteBackward',
  9: 'insertTab',
  13: 'insertNewline',
  27: 'cancel',
  32: 'insertSpace',
  37: 'moveLeft',
  38: 'moveUp',
  39: 'moveRight',
  40: 'moveDown',
  46: 'deleteForward'
};

export var MODIFIED_KEY_EVENTS = {
  8: 'deleteForward',
  9: 'insertBacktab',
  37: 'moveLeftAndModifySelection',
  38: 'moveUpAndModifySelection',
  39: 'moveRightAndModifySelection',
  40: 'moveDownAndModifySelection'
};

Additional

To pause or resume the keyResponder:

keyResponder.pause();
keyResponder.resume();

Installation

• git clone this repository
• npm install
• bower install

Running

• ember server
• Visit your app at http://localhost:4200.

Running Tests

• ember test
• ember test --server

Building

• ember build

For more information on using ember-cli, visit http://www.ember-cli.com/.