Undoo

Undo/redo manager

Installation

Node.js

npm install undoo --save

Browser

Local

<script src="node_modules/undoo/dist/undoo.min.js"></script>

CDN unpkg

<script src="https://unpkg.com/undoo/dist/undoo.min.js"></script>

Example

const Undoo = require('undoo');
 
const myHistory = new Undoo();
 
myHistory
    .save('one')
    .save('two')
    .save('three')
    .save('four');
 
myHistory.undo((item)=>{
    console.log(item); //=> three
});
 
myHistory.current(); //=> three
 
myHistory.redo((item)=>{
    console.log(item); //=> four
});
 

Use provider

const Undoo = require('undoo');
 
const myHistory = new Undoo({
    provider: () => document.getElementById('myTextArea').value
});
 
myHistory.save();
 

API

Undoo

Kind: global class

• Undoo
  • new Undoo([opts])
  • instance
    • .canUndo() ⇒ boolean
    • .canRedo() ⇒ boolean
    • .import(history) ⇒ Undoo
    • .history() ⇒ Array
    • .save([item]) ⇒ Undoo
    • .suspendSave([state]) ⇒ Undoo
    • .allowedSave() ⇒ boolean
    • .clear() ⇒ Undoo
    • .undo([callback]) ⇒ Undoo
    • .redo([callback]) ⇒ Undoo
    • .current() ⇒ *
    • .count() ⇒ number
    • .initialState() ⇒ *
    • .onUpdate(callback) ⇒ Undoo
    • .onMaxLength(callback) ⇒ Undoo
    • .onBeforeSave(callback) ⇒ Undoo
  • inner
    • ~undoCallback : function
    • ~redoCallback : function
    • ~updateCallback : function
    • ~maxLengthCallback : function
    • ~beforeSaveCallback : function

new Undoo([opts])

Create instance

Param	Type	Default	Description
[opts]	Object		configuration object
[opts.provider]	function		optional function called on save that returns new state for history
[opts.maxLength]	number	20	max length history

undoo.canUndo() ⇒ boolean

Check if undo is available

Kind: instance method of Undoo

undoo.canRedo() ⇒ boolean

Kind: instance method of Undoo
Check: if redo is available

undoo.import(history) ⇒ Undoo

Import external history

Kind: instance method of Undoo

Param	Type
history	Array

undoo.history() ⇒ Array

Get history

Kind: instance method of Undoo

undoo.save([item]) ⇒ Undoo

Save history

Kind: instance method of Undoo

Param	Type
[item]	*

undoo.suspendSave([state]) ⇒ Undoo

Suspend save method

Kind: instance method of Undoo

Param	Type	Default
[state]	boolean	true

undoo.allowedSave() ⇒ boolean

Check if save is allowed

Kind: instance method of Undoo

undoo.clear() ⇒ Undoo

Clear history

Kind: instance method of Undoo

undoo.undo([callback]) ⇒ Undoo

Undo

Kind: instance method of Undoo

Param	Type	Description
[callback]	undoCallback	callback function

undoo.redo([callback]) ⇒ Undoo

Redo

Kind: instance method of Undoo

Param	Type	Description
[callback]	redoCallback	callback function

undoo.current() ⇒ *

Get current item in history

Kind: instance method of Undoo

undoo.count() ⇒ number

Count history items, the first element is not considered

Kind: instance method of Undoo

undoo.initialState() ⇒ *

Get initial state history

Kind: instance method of Undoo

undoo.onUpdate(callback) ⇒ Undoo

Triggered when history is updated

Kind: instance method of Undoo

Param	Type	Description
callback	updateCallback	callback function

undoo.onMaxLength(callback) ⇒ Undoo

Triggered when maxLength is exceeded

Kind: instance method of Undoo

Param	Type	Description
callback	maxLengthCallback	callback function

undoo.onBeforeSave(callback) ⇒ Undoo

Triggered before save

Kind: instance method of Undoo

Param	Type	Description
callback	beforeSaveCallback	callback function

Example

// If callback returns `false` the save command will not be executed
myHistory.onBeforeSave(()=>false)
 
// You can overwrite item before save
myHistory.onBeforeSave((item)=>{
     return item.toUpperCase();
})

Undoo~undoCallback : function

undo callback

Kind: inner typedef of Undoo

Param	Type	Description
item	*	current history item

Undoo~redoCallback : function

redo callback

Kind: inner typedef of Undoo

Param	Type	Description
item	*	current history item

Undoo~updateCallback : function

onUpdate callback

Kind: inner typedef of Undoo

Param	Type	Description
item	*	current history item
action	string	action that has called update event. Can be: redo, undo, save, clear
history	Array	history array
istance	Undoo

Undoo~maxLengthCallback : function

onMaxLength callback

Kind: inner typedef of Undoo

Param	Type	Description
item	*	current history item
history	Array	history array
istance	Undoo

Undoo~beforeSaveCallback : function

onBeforeSave callback

Kind: inner typedef of Undoo

Param	Type	Description
item	*	current history item
istance	Undoo

Changelog

You can view the changelog here

License

Undoo is open-sourced software licensed under the MIT license

Author

Fabio Ricali