解读extjs源码之AbstractSelectionModel.js

最新推荐文章于 2018-05-14 17:41:15 发布

原创最新推荐文章于 2018-05-14 17:41:15 发布 · 1k 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#extjs #function #constructor #licensing #delete #class

本文介绍ExtJS 3.3.1中AbstractSelectionModel的实现细节，该类为ExtJS Grid提供选择模型的基础接口，并说明如何通过锁定机制来控制选择行为。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

/*!
 * Ext JS Library 3.3.1
 * Copyright(c) 2006-2010 Sencha Inc.
 * licensing@sencha.com
 * http://www.sencha.com/license
 * --------------------------
 * @note by howl
 */
/**
 * @class Ext.grid.AbstractSelectionModel
 * @extends Ext.util.Observable
 * <Abstract base class for grid SelectionModels.  It provides the interface that should be
 * implemented by descendant classes.  This class should not be directly instantiated.>
 * 這是針對grid的選擇模型的抽象基類，它提供應該被子類實現的接口.這個類不能直接的被實例化
 * @constructor
 */
 Ext.grid.AbstractSelectionModel = Ext.extend(Ext.util.Observable, {
 	/**
     * <The GridPanel for which this SelectionModel is handling selection. Read-only.>
     * @type Object
     * @property grid
     */
	   constructor : function(){
	    this.locked = false;
	    Ext.grid.AbstractSelectionModel.superclass.constructor.call(this);//調用其父類的構造方法
	},
	
	/** @ignore <Called by the grid automatically. Do not call directly.> 
	 * 會被grid自動調用，不要人為直接調用
	 */
	 init : function(grid){
        this.grid = grid;
        if(this.lockOnInit){
            delete this.lockOnInit;
            this.locked = false;
            this.lock();
        }
        this.initEvents();
    },
    
     /**
     * <Locks the selections.>
     * 為選擇加鎖
     */
    
    lock : function(){
    	if(!this.locked){
    		this.locked = true;
    		// <If the grid has been set, then the view is already initialized.>如果grid已經被設置了，那麼說明view已經被初始化了
    		var g = this.grid;
    		if(g){
    			 g.getView().on({
                    scope: this,
                    beforerefresh: this.sortUnLock,
                    refresh: this.sortLock
                });
    		}else{
    			this.lockOnInit = true;
    		}
    	}
    },
    
    // <set the lock states before and after a view refresh>在view刷新之前和之後設置鎖的狀態
     sortLock : function() {
        this.locked = true;
    },
    
    // <set the lock states before and after a view refresh>在view刷新之前和之後設置鎖的狀態
    sortUnLock : function() {
        this.locked = false;
    },
    
    /**
     * <Unlocks the selections.>為選區解鎖
     */
      unlock : function(){
        if(this.locked){
            this.locked = false;
            var g = this.grid,
                gv;
                
            // <If the grid has been set, then the view is already initialized.>如果grid已經被設置，說明view已經初始化了
            if(g){
                gv = g.getView();
                gv.un('beforerefresh', this.sortUnLock, this);
                gv.un('refresh', this.sortLock, this);    
            }else{
                delete this.lockOnInit;
            }
        }
    },
    
    /**
     * <Returns true if the selections are locked.>如果選區被鎖定，返回true
     * @return {Boolean}
     */
    isLocked : function(){
        return this.locked;
    },

    destroy: function(){
        this.unlock();
        this.purgeListeners();
    }
});
})