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扩展Flex DataGridColumn以实现自定义排序功能

adobe datagrid flex

0

Anand · 技术社区 · 15 年前

我扩展了DataGrid列,因为我想包含一个自定义itemToLabel函数(以便能够在DataGrid中显示嵌套数据。请参阅 this 问题。

private function mySortCompareFunction(obj1:Object, obj2:Object):int{
    var currentData1:Object = obj1;
    var currentData2:Object = obj2;

    //some logic here to get the currentData if the object is nested.

    if(currentData1 is int && currentData2 is int){
        var int1:int = int(currentData1);
        var int2:int = int(currentData2);
        var result:int = (int1>int2)?-1:1; 
        return result;
    }
    //so on for string and date
}

在CustomDataGridColumn的构造函数中,我将: 超级(列名); SortComparenction=mySortCompareFunction;

每当我尝试对列进行排序时,都会出现错误“ Error: Find criteria must contain at least one sort field value. "

当我调试并逐步完成每个步骤时,我看到前几次,函数被正确调用,但在接近结束时,出现了这个错误。

谢谢

4 回复 | 直到 7 年前

1

Koen Weyn 15 年前

我也看到了这个错误,我跟踪到了其中一个包含“null”的单元格。如果我没记错的话,当其中一列的“dataField”属性错误时,这个错误也会出现。

科恩·韦恩

2

1

Anand 15 年前

为了说明我是如何解决这个问题的(为了其他人的利益):

dataField data.name , data.title 因为我是从嵌套对象中获取数据的),所以我创建了自己的字段 nestedDataField

public class DataGridColumnNested extends DataGridColumn{
[Bindable] public var nestedDataField:String;

private function mySortCompareFunction(obj1:Object, obj2:Object):int{
    var currentData1:Object = obj1;
    var currentData2:Object = obj2;

    //some logic here to get the currentData if the object is nested.

    if(currentData1 is int && currentData2 is int){
        var int1:int = int(currentData1);
        var int2:int = int(currentData2);
        var result:int = (int1>int2)?-1:1; 
        return result;
    }
    //so on for string and date
}
}

然后,我将数据字段条目分配给这个新变量

<custom:DataGridColumnNested headerText="Name" nestedDataField="data.name"/>

3

1

David Vermeir 14 年前

我经常发现使用标准数据字段更容易,只需在valueobject中编写一个getter函数用作数据字段。例如:

//file SomeObject.as with a nested object as property
public class SomeObject
{
   public var someProperty:AnotherObject;

   public function get someString():String;
   {
     if(someProperty)
        return someProperty.someString;
     else
        return "";
   }
}

//your nested class, AnotherObject.as
public class AnotherObject
{
   public var someString:String;
}

//this way sorting and the label will work without custom label/compare functions
<mx:DataGridColumn headerText="" dataField="someString"/>

4

1

AntuanF1 14 年前

    <mx:DataGridColumn headerText="email" 
dataField="user.email" textAlign="center" />

    <mx:DataGridColumn headerText="email" 
labelFunction="emailLabelFunction" 
sortCompareFunction="emailsCompareFunction2" 
textAlign="center" />



public static function emailLabelFunction(item:Object, column:DataGridColumn):String{

   if (item!=null){
    var user:User = (item as TpAnnouncementUser).user as User;

    return user.email;
   }else{

    return "";
   }
}

public static function emailCompareFunction(obj1:Object, obj2:Object):int{

    var dato1:String = User(obj1).email.toLowerCase();
    var dato2:String = User(obj2).email.toLowerCase();

    return ObjectUtil.compare(dato1, dato2);

}


    public static function emailsCompareFunction2(obj1:Object, obj2:Object):int{

    var dato3:User = (TpAnnouncementUser(obj1).user as User);
    var dato4:User = (TpAnnouncementUser(obj2).user as User);

    return emailCompareFunction(dato3, dato4);