Apache flex 是否可以使灵活列表控件中的项不可选择?
是否可以使列表控件中的项不可选择?如果是,这将如何实现 到目前为止,我试过一件事。我所做的是在FlexEvent.data_更改事件中使用自定义项呈现程序来检查data属性中的值。如果未设置该值,我尝试将项目渲染器的可选属性设置为false。不幸的是,这似乎不起作用Apache flex 是否可以使灵活列表控件中的项不可选择?,apache-flex,actionscript-3,Apache Flex,Actionscript 3,是否可以使列表控件中的项不可选择?如果是,这将如何实现 到目前为止,我试过一件事。我所做的是在FlexEvent.data_更改事件中使用自定义项呈现程序来检查data属性中的值。如果未设置该值,我尝试将项目渲染器的可选属性设置为false。不幸的是,这似乎不起作用 有什么想法吗?我可以在下面添加一个分隔符组件。下面是一个示例,其中去掉了渲染器逻辑,保留了可选择性逻辑: package com.example.ui { import flash.events.MouseEvent; impor
有什么想法吗?我可以在下面添加一个分隔符组件。下面是一个示例,其中去掉了渲染器逻辑,保留了可选择性逻辑:
package com.example.ui {
import flash.events.MouseEvent;
import flash.ui.Keyboard;
import mx.controls.List;
import mx.controls.listClasses.IListItemRenderer;
public class MyList extends List
{
public function MyList()
{
super();
}
/** Override mouse navigation */
protected override function mouseEventToItemRenderer(event:MouseEvent):IListItemRenderer {
var row:IListItemRenderer = super.mouseEventToItemRenderer(event);
if (row != null && isSelectable(row.data)) {
return null;
}
return row;
}
/** Override keyboard navigation */
protected override function moveSelectionVertically(code:uint, shiftKey:Boolean, ctrlKey:Boolean):void {
super.moveSelectionVertically(code, shiftKey, ctrlKey);
if (code == Keyboard.DOWN && isSeparatorData(selectedItem)) {
caretIndex++;
}
if (code == Keyboard.UP && isSeparatorData(selectedItem)) {
caretIndex--;
}
finishKeySelection();
}
/**
* Define this mechanism in a way that makes sense for your project.
*/
protected function isSelectable(data:Object):Boolean {
return data != null && data.hasOwnProperty("type") && data.type == "separator";
}
}
}
另一种更好地处理可滚动列表和连续分隔符的方法(仍不完善):
protected override function moveSelectionVertically(code:uint, shiftKey:Boolean, ctrlKey:Boolean):void {
super.moveSelectionVertically(code, shiftKey, ctrlKey);
var newCode:uint = singleLineCode(code);
var item:Object = selectedItem;
var itemChanged:Boolean = true;
while (!isNaN(newCode) && itemChanged && isSeparatorData(item)) {
super.moveSelectionVertically(newCode, shiftKey, ctrlKey);
itemChanged = (item === selectedItem);
item = selectedItem;
}
}
private function singleLineCode(code:uint):uint {
switch (code) {
case Keyboard.UP:
case Keyboard.PAGE_UP:
return Keyboard.UP;
break;
case Keyboard.DOWN:
case Keyboard.PAGE_DOWN:
return Keyboard.DOWN;
break;
default:
return NaN;
break;
}
return code;
}
所以我想出了自己的解决办法。它与您的类似,似乎可以做到这一点,并覆盖所有的基础,除了破解向上和向下翻页键。我之所以说hack,是因为我不确定它是否以与列表控件相同的方式处理caretIndex的增加或减少。基本上,它只是手动将caretIndex设置为下一个可选项之前的索引,并将keycode更改为简单的向上或向下
protected function disabledFilterFunction( data:Object ):Boolean
{
return ( data != null && data.data == null );
}
override protected function mouseEventToItemRenderer( event:MouseEvent ):IListItemRenderer
{
var item:IListItemRenderer = super.mouseEventToItemRenderer( event );
if( item && item.data && disabledFilterFunction( item.data ) )
return null;
return item;
}
override protected function moveSelectionVertically( code:uint, shiftKey:Boolean, ctrlKey:Boolean ):void
{
var i:int;
var newIndex:int;
switch( code )
{
case Keyboard.UP:
newIndex = getPreviousUnselectableIndex( caretIndex - 1 );
break;
case Keyboard.DOWN:
newIndex = getNextUnselectableIndex( caretIndex + 1 );
break;
case Keyboard.HOME:
newIndex = getFirstSelectableIndex();
code = Keyboard.UP;
break;
case Keyboard.END:
newIndex = getLastSelectableIndex();
code = Keyboard.DOWN;
break;
case Keyboard.PAGE_UP:
{
newIndex = Math.max( getFirstSelectableIndex(), getPreviousUnselectableIndex( caretIndex - ( rowCount - 2 ) ) );
code = Keyboard.UP;
break;
}
case Keyboard.PAGE_DOWN:
{
newIndex = Math.min( getLastSelectableIndex(), getNextUnselectableIndex( caretIndex + ( rowCount - 1 ) ) );
code = Keyboard.DOWN;
break;
}
}
if( newIndex > -1 && newIndex < collection.length )
{
caretIndex = newIndex;
super.moveSelectionVertically( code, shiftKey, ctrlKey );
}
}
private function getFirstSelectableIndex():int
{
var result:int = -1;
for( var i:int = 0; i < collection.length; i++ )
{
if( !disabledFilterFunction( collection[i] ) )
{
result = i + 1;
break;
}
}
return result;
}
private function getLastSelectableIndex():int
{
var result:int = -1;
for( var i:int = collection.length - 1; i > -1; i-- )
{
if( !disabledFilterFunction( collection[i] ) )
{
result = i - 1;
break;
}
}
return result;
}
private function getPreviousUnselectableIndex( startIndex:int ):int
{
var result:int = -1;
for( var i:int = startIndex; i > -1; i-- )
{
if( !disabledFilterFunction( collection[i] ) )
{
result = i + 1;
break;
}
}
return result;
}
private function getNextUnselectableIndex( startIndex:int ):int
{
var result:int = collection.length;
for( var i:int = startIndex; i < collection.length; i++ )
{
if( !disabledFilterFunction( collection[i] ) )
{
result = i - 1;
break;
}
}
return result;
}
受保护函数disabledFilterFunction(数据:对象):布尔值
{
返回(数据!=null&&data.data==null);
}
重写受保护的函数MouseeEventToItemRenderer(事件:MouseeEvent):IListItemRenderer
{
var item:IListItemRenderer=super.mouseeventtoitemdrenderer(事件);
if(item&&item.data&&disabledFilterFunction(item.data))
返回null;
退货项目;
}
覆盖受保护的函数MoveSelectionVertical(代码:uint,shiftKey:Boolean,ctrlKey:Boolean):无效
{
变量i:int;
var-newIndex:int;
开关(代码)
{
case Keyboard.UP:
newIndex=getPreviousUnselectableIndex(caretIndex-1);
打破
case Keyboard.DOWN:
newIndex=getNextUnselectableIndex(caretIndex+1);
打破
case.HOME:
newIndex=getFirstSelectableIndex();
code=Keyboard.UP;
打破
case.END:
newIndex=getLastSelectableIndex();
code=Keyboard.DOWN;
打破
case Keyboard.PAGE\u UP:
{
newIndex=Math.max(getFirstSelectableIndex(),getPreviousUnselectableIndex(caretIndex-(rowCount-2));
code=Keyboard.UP;
打破
}
case KEYBORD.PAGE_向下:
{
newIndex=Math.min(getLastSelectableIndex(),getNextUnselectableIndex(caretIndex+(rowCount-1));
code=Keyboard.DOWN;
打破
}
}
if(newIndex>-1&&newIndex-1;i--)
{
if(!disabledFilterFunction(集合[i]))
{
结果=i-1;
打破
}
}
返回结果;
}
私有函数getPreviousUnselectableIndex(startIndex:int):int
{
var结果:int=-1;
对于(变量i:int=startIndex;i>-1;i--)
{
if(!disabledFilterFunction(集合[i]))
{
结果=i+1;
打破
}
}
返回结果;
}
私有函数getNextUnselectableIndex(startIndex:int):int
{
var结果:int=collection.length;
for(var i:int=startIndex;i
我只是想增加我的两种感觉。我也在想同样的事情(如何将列表设置为不可选择),我意识到spark组件数据组正好可以做到这一点。当然,您需要使用flex 4,但是如果您是,并且想知道我是否可以将列表设置为不可选择,我建议使用数据组。我可以通过分别在caretIndex++和caretIndex之前执行verticalScrollPosition++和verticalScrollPosition来解决第一个/最后一个项目不可选择的问题(在上面Michael链接的示例中)。我不敢相信修复这么简单,但它是 我自己也在寻找解决方案,下面是我提出的解决方案。请注意,我使用的是火花列表。我希望有人觉得这有帮助
<s:List id="myListView"
itemRenderer="spark.skins.spark.DefaultComplexItemRenderer"
horizontalCenter="0"
verticalCenter="0"
borderVisible="false"
dataProvider="{myItems}"
change="changeHandler(event)" changing="changingHandler(event)"
requireSelection="false"
selectedIndex="-1" >
<s:layout>
<s:TileLayout verticalGap="0" />
</s:layout>
</s:List>
<fx:script>
<![CDATA[
import mx.collections.ArrayCollection;
import spark.events.IndexChangeEvent;
[Bindable]
public var myItems = new ArrayCollection;
protected function startup():void {
// Here's where you'd build up your items if they
// need to be built dynamically.
}
protected function changeHandler(event:IndexChangeEvent):void
{
var currentIndx:int = event.currentTarget.selectedIndex;
var selectedItem:UIComponent = event.currentTarget.selectedItem as UIComponent;
// Do whatever you need to do on selection here
}
protected function canMicrophoneChange(event:IndexChangeEvent):void
{
var currentIndx:int = event.currentTarget.selectedIndex;
var selectedItem:UIComponent = event.currentTarget.selectedItem as UIComponent;
// This will cancel the select if the item was not enabled.
if (selectedItem.enabled == false) event.preventDefault();
}
]]>
</fx:script>
这部分起作用。它似乎没有说明列表是可滚动的。例如,假设列表的集合/数据提供程序中有20项,而列表行数(可变行)为10。因此,将呈现滚动条。然后假设集合中的索引9(第一次查看列表时最后可见的行项目)是一个分隔符。如果您使用箭头键在列表中向下移动,列表将选择索引9处的分隔符。很好,我们到目前为止还没有在可滚动列表中使用此分隔符。它也没有处理连续的分离器(不太可能用于分离器,但是