ExtJs 4...如何扩展Extjs4组件？

Question

谁可以帮助我如何扩展extjs组件使用extjs版本4。我正在寻找相同的正确语法。请帮帮我！

Answer 1

下面是在ExtJS 4中扩展textfield的示例代码。

除了使用现有的配置和方法之外，这个扩展组件还创建了一个新的config属性，并创建了一个与事件关联的新方法。

component的用途很简单，如果值是必填项，它将以红色显示标签；如果值为readOnly，则修改字段的背景颜色；当聚焦时，还会更改字段的背景颜色。

代码有正确的注释。希望能有所帮助。

Ext.define('Ext.pnc.Textfield', {

extend: 'Ext.form.field.Text',//Extending the TextField

alias: 'widget.pnctextfield',//Defining the xtype

config:{
    focusCls:'focusClassFieldPnC',//Providing value for existing config property.
    testConfig:'testConfigValue'//Creating a new config. Accessor functions will be created for this one by ExtJS engine
},

constructor:function(cnfg){
    this.callParent(arguments);//Calling the parent class constructor
    this.initConfig(cnfg);//Initializing the component
    this.on('beforerender',this.beforeRender);//Associating a new defined method with an event
},

//Defining a method below and associating this with an event in the constructor above
beforeRender:function(){

    if(!this.allowBlank){
        this.labelStyle =   'color:#FF0000';        
    }

    if(this.readOnly){
        this.fieldCls   =   'readOnlyClass';
    }
},

//Over-riding a function which already exists in parent class. Note that this has not been associated with any event in constructor as it already defined in parent class
afterRender:function(){
    console.log('after render function');
    this.callParent();//Calling the parent class method. This can be omitted if not     required and is not a must
}
});

.readOnlyClass{
background:#FF0000 !important
}


.focusClassFieldPnC{
background:#00ff00 !important
}

Answer 2

Ext.define('myApp.Grid', {
        extend: 'Ext.Grid',
        alias: 'widget.mygrid'
        ....
        ....
        }

现在可以使用xtype:'mygrid‘

Answer 3

Ext.define('BS.view.MyGrid' , {
    extend: 'Ext.grid.Panel',
    alias: 'widget.my-grid',

    // Non-complex config types (booleans, integers, strings) go here
    width: 1000,
    autoHeight: true

    initComponent: function() {
        Ext.apply(this, {
            // complex configs (objects / arrays) go here
            columns: colModel,  
        });

        this.callParent(arguments);
    }
});