自定义ExtJS控件之下拉树和下拉表格附源码

简介

在Ext官方的例子中只有下拉列表控件，但是在实际业务中只有下拉列表无法满足需求的，像下拉树和下拉表格都是很常见的控件，对于刚使用Ext的人来说，自定义一个控件好难，其实多读官方的源码有些事情就不会那么难了。下面是下拉树的代码：

Ext.define('ComboTreeBox',{ 
extend : 'Ext.form.field.ComboBox', 

multiSelect : true, 

createPicker : function(){ 
var me = this; 

//创建树控件 
var picker = Ext.create('Ext.tree.Panel', { 
store: me.store, 
rootVisible: false, 
selModel: { 
mode: me.multiSelect ? 'SIMPLE' : 'SINGLE' 
}, 
floating: true, 
hidden: true, 
focusOnToFront: false 
}); 
//注册事件用于选择用户选择的值 
me.mon(picker, { 
itemclick: me.onItemClick, 
refresh: me.onListRefresh, 
scope: me 
}); 

me.mon(picker.getSelectionModel(), { 
beforeselect: me.onBeforeSelect, 
beforedeselect: me.onBeforeDeselect, 
selectionchange: me.onListSelectionChange, 
scope: me 
}); 
this.picker = picker; 
return picker; 
}, 

onItemClick: function(picker, record){ 
/* 
* If we're doing single selection, the selection change events won't fire when 
* clicking on the selected element. Detect it here. 
*/ 
var me = this, 
selection = me.picker.getSelectionModel().getSelection(), 
valueField = me.valueField; 

if (!me.multiSelect && selection.length) { 
if (record.get(valueField) === selection[0].get(valueField)) { 
// Make sure we also update the display value if it's only partial 
me.displayTplData = [record.data]; 
me.setRawValue(me.getDisplayValue()); 
me.collapse(); 
} 
} 
} 
});

下拉树的代码很简单，只要集成Ext.form.field.ComboBox类，然后重写createPicker方法就可以了，同理下拉表格也是如此，下面是下拉表格的代码：

Ext.define('ComboGridBox',{ 
extend : 'Ext.form.field.ComboBox', 

multiSelect : true, 

createPicker : function(){ 
var me = this; 

var picker = Ext.create('Ext.grid.Panel', { 
title : '下拉表格', 
store: me.store, 
frame : true, 
resizable : true, 
columns : [{ 
text : '#ID', 
dataIndex : 'id' 
},{ 
text : '名称' , 
dataIndex : 'name' 
},{ 
text : '描述' , 
dataIndex : 'desc' 
}], 
selModel: { 
mode: me.multiSelect ? 'SIMPLE' : 'SINGLE' 
}, 
floating: true, 
hidden: true, 
width : 300, 
columnLines : true, 
focusOnToFront: false 
}); 
me.mon(picker, { 
itemclick: me.onItemClick, 
refresh: me.onListRefresh, 
scope: me 
}); 

me.mon(picker.getSelectionModel(), { 
beforeselect: me.onBeforeSelect, 
beforedeselect: me.onBeforeDeselect, 
selectionchange: me.onListSelectionChange, 
scope: me 
}); 
this.picker = picker; 
return picker; 
}, 

onItemClick: function(picker, record){ 
/* 
* If we're doing single selection, the selection change events won't fire when 
* clicking on the selected element. Detect it here. 
*/ 
var me = this, 
selection = me.picker.getSelectionModel().getSelection(), 
valueField = me.valueField; 

if (!me.multiSelect && selection.length) { 
if (record.get(valueField) === selection[0].get(valueField)) { 
// Make sure we also update the display value if it's only partial 
me.displayTplData = [record.data]; 
me.setRawValue(me.getDisplayValue()); 
me.collapse(); 
} 
} 
}, 

matchFieldWidth : false, 

onListSelectionChange: function(list, selectedRecords) { 
var me = this, 
isMulti = me.multiSelect, 
hasRecords = selectedRecords.length > 0; 
// Only react to selection if it is not called from setValue, and if our list is 
// expanded (ignores changes to the selection model triggered elsewhere) 
if (!me.ignoreSelection && me.isExpanded) { 
if (!isMulti) { 
Ext.defer(me.collapse, 1, me); 
} 
/* 
* Only set the value here if we're in multi selection mode or we have 
* a selection. Otherwise setValue will be called with an empty value 
* which will cause the change event to fire twice. 
*/ 
if (isMulti || hasRecords) { 
me.setValue(selectedRecords, false); 
} 
if (hasRecords) { 
me.fireEvent('select', me, selectedRecords); 
} 
me.inputEl.focus(); 
} 
console.log(me.getValue()); 
}, 

doAutoSelect: function() { 
var me = this, 
picker = me.picker, 
lastSelected, itemNode; 
if (picker && me.autoSelect && me.store.getCount() > 0) { 
// Highlight the last selected item and scroll it into view 
lastSelected = picker.getSelectionModel().lastSelected; 
itemNode = picker.view.getNode(lastSelected || 0); 
if (itemNode) { 
picker.view.highlightItem(itemNode); 
picker.view.el.scrollChildIntoView(itemNode, false); 
} 
} 
} 
});

下拉表格也是继承了Ext.form.field.ComboBox这个类，重写了createPicker方法。

开发下拉树和下拉表格看起来so easy，只要研究透了Ext的运行机制，一切都会so easy

控件效果





实例下载

实例中的资源为myeclipse项目，导入即可运行，自己添加ext的js和css文件，实例中没有ext的基础文件。
下载地址