Undo

class webix.Undo()

Undo mixin

References

mixins

PowerArray().

helpers

copy(), extend().

Referenced by

mixins

EditAbility().

External references

Official documentation page.

Code

webix.Undo= {
    $init:function(){
        this._undoHistory = webix.extend([],webix.PowerArray,true);
        this._undoCursor = -1;
    },
    undo_setter: function(value){
        if(value){
            this._init_undo();
            this._init_undo = function(){};
        }
        return value;
    },
    _init_undo: function(){
        var view = this;

        // drag-n-drop
        this.attachEvent("onBeforeDrop", function(context){
            if(context.from == context.to){
                var item = view._draggedItem = webix.copy(this.getItem(context.start));
                if(this.data.branch){
                    item.$index = this.getBranchIndex(item.id);
                }
                else
                    item.$index = this.getIndexById(item.id);
            }
        });
        this.data.attachEvent("onDataMove", function( sid ){
            if(view._draggedItem && view._draggedItem.id == sid){
                var data = view._draggedItem;
                view._draggedItem = null;
                view._addToHistory(sid, data, "move");
            }
        });

        // add, remove
        this.data.attachEvent("onBeforeDelete", function(id){
            if(this.getItem(id)){
                var item = view._deletedItem = webix.copy(this.getItem(id));
                if(this.branch){
                    item.$index = this.getBranchIndex(id);
                    if(this.branch[id])
                        item.$branch = webix.copy(this.serialize(id));
                }
                else
                    item.$index = this.getIndexById(id);
            }
        });
        this.data.attachEvent("onDataUpdate", function(id, data, old){
            view._addToHistory(id+"", old, "update");
        });
        this.data.attachEvent("onStoreUpdated", function(id, item, mode){
            var data = null;
            if(id){
                if(mode == "add"){
                    data = webix.copy(item);
                }
                else if( mode == "delete") {
                    data = view._deletedItem;
                }

                if(data)
                    view._addToHistory(id, data, mode);
            }
        });

        // id change
        this.data.attachEvent("onIdChange", function(oldId,newId){
            if(typeof oldId == "object")
                oldId = oldId.row;
            for(var i =0; i < view._undoHistory.length; i++){
                if(view._undoHistory[i].id == oldId){
                    view._undoHistory[i].id = newId;
                }
            }
        });
    },
    _addToHistory: function(id, data, action){
        if(!this._skipHistory && this._settings.undo){
            this._undoHistory.push({id: id, action: action, data: data});
            if(this._undoHistory.length==20)
                this._undoHistory.splice(0,1);
            if(!this._skipCursorInc)
                this._undoCursor = this._undoHistory.length - 1;
        }
    },
    ignoreUndo: function(func, master){
         this._skipHistory = true;
         func.call(master||this);
         this._skipHistory = false;
    },
    removeUndo: function(id){
        for( var i = this._undoHistory.length-1; i >=0; i--){
            if(this._undoHistory[i].id == id){
                if(this._undoHistory[i].action == "id"){
                    id = this._undoHistory[i].data;
                }
                this._undoHistory.removeAt(i);
            }
        }
        this._undoCursor = this._undoHistory.length - 1;
    },
    undo: function(id){
        if(id){
            this.ignoreUndo(function(){
                var data, i;
                for( i = this._undoHistory.length-1; !data && i >=0; i--){
                    if(this._undoHistory[i].id == id)
                        data = this._undoHistory[i];
                }

                if(data){
                    /*if(data.action == "id")
                        id = data.data;*/
                    this._undoAction(data);
                    this._undoHistory.removeAt(i+1);
                    this._undoCursor = this._undoHistory.length - 1;
                }
            });
        }
        else{
            var data = this._undoHistory[this._undoCursor];
            if(data){
                this.ignoreUndo(function(){
                    this._undoAction(data);
                    this._undoHistory.removeAt(this._undoCursor);
                });
                this._undoCursor--;
                /*if(data.action == "id")
                    this.undo();*/
            }
        }
    },
    _undoAction: function(obj){
        if(obj.action == "delete"){
            var branch = null,
                parentId = obj.data.$parent;

            if(obj.data.$branch){
                branch = {
                    parent: obj.id,
                    data: webix.copy(obj.data.$branch)
                };
                delete obj.data.$branch;
                if(parentId && !this.data.branch[parentId])
                    parentId = 0;
            }

            this.add(obj.data, obj.data.$index, parentId);
            if(branch){
                this.parse(branch);
            }
        }
        else if(obj.action == "add"){
            this.remove(obj.id);
        }
        else if(obj.action == "update"){
            this.updateItem(obj.id, obj.data);
        }
        else if(obj.action == "move"){
            if(obj.data.$parent){
                if(this.getItem(obj.data.$parent))
                    this.move(obj.id, obj.data.$index, null, {parent: obj.data.$parent});
            }
            else
                this.move(obj.id, obj.data.$index);
        }
        /*else if(obj.action == "id"){
            this.data.changeId(obj.id, obj.data);
        }*/
    }
};

/*
    Behavior:DataLoader - load data in the component

    @export
        load
        parse
*/