Navigation within ItemRenderer - apache-flex

How can we navigate within an itemRenderer?
For example, in Views we use the View.navigator (ViewNavigator) to push and pop views, there is no such feature in ItemRenderer.
Navigation within a View (Easy)
<s:View>
<s:HGroup >
<s:Button label="Questionnaire" click="navigator.pushView(view.QuestionnaireCategory1View)"/>
</s:HGroup>
Navigation within a Item Renderer (Impossible?)
<?xml version="1.0" encoding="utf-8"?>
<s:ItemRenderer xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
autoDrawBackground="true" height="56">
<s:HGroup>
<s:Button text="Button" click="?????????"/>
</s:HGroup>
</s:ItemRenderer>

You want to use bubbling events to catch when the user interacts with an item renderer.
<s:ItemRenderer xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark">
<s:HGroup>
<s:Button text="Button" click="dispatchEvent(new Event('buttonClicked', true));"/>
</s:HGroup>
</s:ItemRenderer>
Then when do this with whatever is using your item renderer:
<DataGroup id="group" itemRenderer="YourItemRenderer" dataProvider="{someData}" creationComplete="group.addEventListener('buttonClick', someHandlerFunction);" />
And then within your handler function, do whatever action you wanted to do. In this case, I'm adding the event listener on creation complete of the DataGroup, but you can add it to the creation complete event of the main container. This way you keep your item renderer decoupled and reusable, as well as using proper software practices (data in, events out).

In when you create your itemRenderer
<comp:MyItemRenderer navigator="{navigator}"/>
In your itemRenderer (here call MyItemRenderer)
<s:ItemRenderer xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
autoDrawBackground="true" height="56">
<fx:Script>
<![CDATA[
import spark.components.ViewNavigator;
private var _navigator:ViewNavigator;
public function set navigator(value:ViewNavigator):void
{
_navigator = value;
}
]]>
</fx:Script>
<s:HGroup>
<s:Button label="Button" click="{_navigator.pushView(view.QuestionnaireCategory1View)}"/>
</s:HGroup>

Related

How to access MXML component instance in ItemRenderer

I have been developing an Adobe Flex (v3.5 Flex SDK) based application and I have a question on How we can access (call) a method written in MXML file (embeded in script tag) from the ItemRenderer file.
The MXML component has a datagrid and for one of the columns, the itemrenderer is my own custom item renderer.
In my custom item renderer, for some event I need to call a method which exist in its parent MXML component. How do we get access to its parent MXML instance ?
I have explored for this in google and found that we can access to 'data' object which refers to the dataProvider of the datagrid. But I wanted access to the instance of MXML component (so that I can call a method in it) which has the datagrid.
The AdvancedDataGridColumn in AdvancedDataGrid is like this
<mx:AdvancedDataGridColumn dataField="total" headerText="Total" width="120" itemRenderer="renderers.MyItemRenderer"/>
Here MyItemRenderer is a separate action script file.
Appreciate the response.
Thanks
Raagu
As Raghavendra Nilekani suggested This works:
TestGrid.mxml
<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600">
<fx:Script>
<![CDATA[
[Bindable]
public var data:Array = [
{name:"name",value:"valeu1",timestamp:"423423"},
{name:"name1",value:"valeu2",timestamp:"423423"},
{name:"name2",value:"valeu3",timestamp:"423423"},
{name:"name3",value:"valeu5",timestamp:"423423"}
]
public function calculateValue():Number{
return Math.random();
}
]]>
</fx:Script>
<fx:Declarations>
</fx:Declarations>
<mx:VBox height="100%" width="100%">
<mx:AdvancedDataGrid dataProvider="{data}">
<mx:columns>
<mx:AdvancedDataGridColumn itemRenderer="ItemRenderer">
</mx:AdvancedDataGridColumn>
</mx:columns>
</mx:AdvancedDataGrid>
</mx:VBox>
</s:Application>
e ItemRendere.mxml
<?xml version="1.0" encoding="utf-8"?>
<s:MXAdvancedDataGridItemRenderer xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx"
focusEnabled="true"
addedToStage="mxadvanceddatagriditemrenderer1_addedToStageHandler(event)"
>
<fx:Script>
<![CDATA[
[Bindable]
var value:Number;
import mx.containers.VBox;
import mx.controls.AdvancedDataGrid;
protected function mxadvanceddatagriditemrenderer1_addedToStageHandler(event:Event):void
{
var grid:AdvancedDataGrid = ((AdvancedDataGrid)(this.owner));
var box:VBox = ((VBox)(grid.owner))
var comp:TestGrid = (TestGrid)(box.owner);
value = comp.calculateValue();
}
]]>
</fx:Script>
<s:Label id="lblData" top="0" left="0" right="0" bottom="0" text="{value}" />
</s:MXAdvancedDataGridItemRenderer>
Anyway I agree with zenbeni that this lead to a not reausable item renderer.

Dragging in spark List does not work in Flex mobile app? Test case and screenshot attached

I would like to reorder items of a List in a Flex mobile app by dragging them around with a finger.
As a first step I have copied the example from Adobe document Using drag-and-drop with list-based controls - but while their example works fine as web application, nothing happens in the mobile app below:
Why doesn't it work (like is some skin missing in the mobile theme?)
Is there a way to make it work (at least reordering items in a mobile List)?
Below is the simple test code I've tried - just put it into a new blank (i.e. without a nav. bar) Flex mobile project in Flash Builder:
<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
applicationDPI="160"
creationComplete="initApp()">
<s:layout>
<s:VerticalLayout/>
</s:layout>
<fx:Script>
<![CDATA[
import mx.collections.ArrayCollection;
private function initApp():void {
srclist.dataProvider =
new ArrayCollection(['Reading', 'Television', 'Movies']);
destlist.dataProvider = new ArrayCollection([]);
}
]]>
</fx:Script>
<s:HGroup>
<s:VGroup>
<s:Label text="Available Activities"/>
<s:List id="srclist"
allowMultipleSelection="true"
dragEnabled="true"
dragMoveEnabled="true"/>
</s:VGroup>
<s:VGroup>
<s:Label text="Activities I Like"/>
<s:List id="destlist"
dropEnabled="true"/>
</s:VGroup>
</s:HGroup>
<s:Button id="b1"
label="Reset"
click="initApp();"/>
</s:Application>
I have found and tried by myself a super workaround on this page.
Just copy classes from his example and add the custom itemRenderer to your source list.
<s:List id="srclist"
allowMultipleSelection="true"
dragEnabled="true"
dragMoveEnabled="true">
<s:itemRenderer>
<fx:Component>
<local:DraggableIconItemRenderer decorator="{DragThumb}" />
</fx:Component>
</s:itemRenderer>
</s:List>
Respect to the author!
Here is the result:

Flex mxml custom component - how to add uicomponents?

how to I pass in a uicomponent to a mxml custom component?
ex: I want to pass in any number of buttons, and I want my custom component to lay them out in a certain order.
MainApp.mxml:
<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx"
minWidth="955" minHeight="600" xmlns:local="*"
>
<local:myComp >
<s:Button label='Button1' />
<s:Button label='Button2' />
<!--I want to add anything else here -->
</local:myComp>
myComp.mxml:
<?xml version="1.0" encoding="utf-8"?>
<s:Group xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx"
creationComplete="init()"
width="400" height="300"
>
<fx:Script>
<![CDATA[
private function init():void {
// how do I access the added components and place them where I want?
// do I use removeChildren and AddChildren?
// addItemsHere.addchild(nextButton);
]]>
</fx:Script>
<s:HGroup id='addItemsHere' />
As your component extends Group, you shall use addElement instead of addChild (and for all other methods with 'child' in their name it shall be replaced with 'element'. So, access to all elements will be like that:
for(var i:int =0; i < numElements; i++){
var button:Button = Button(getElementAt(i));
doWhatIWantWithMyButton(button);
}
It is also better to override createChildren method of your component if you know what to add at the creation moment.
If you don't need very specific button placement, you can set layout property of your component to any desired layout (like VerticalLayout, for example), and those layouts are tunable.
You seem to be trying to recreate functionality that already exists in the SDK. This is wat SkinnableContainer is for.
Depending on your use case, there are two ways to use it:
You only need to add some custom graphic elements to you custom component, but no additional behaviour
In this scenario, you would simple reuse SkinnableContainer and assign it a custom skin, like so:
<s:SkinnableContainer skinClass="MySkin">
<s:Button label='Button1' />
<s:Button label='Button2' />
</s:SkinnableContainer>
With MySkin.mxml perhaps something like:
<s:Skin xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark">
<fx:Metadata>
[HostComponent("spark.components.SkinnableContainer")]
</fx:Metadata>
<s:states>
<s:State name="normal" />
<s:State name="disabled" />
</s:states>
<s:layout>
<s:VerticalLayout/>
</s:layout>
<s:Label text="I'm a SkinnableContainer"/>
<s:Group id="contentGroup" width="100%" height="100%">
</s:SkinnableContainer>
Your Buttons will now automatically be added to the contentGroup; the SkinnableContainer class handles this for you. Note that this Group must have exactly that id; it's a required SkinPart.
You want to add some behaviour to you component
The procedure is the same, but you would now subclass SkinnableContainer (this is usually done in pure ActionScript), write some behaviour in there, and assign the skin to an instance of this class.
public class MyComp extends SkinnableContainer {
//additional behaviour goes here
}
Usage:
<local:MyComp skinClass="MySkin">
<s:Button label='Button1' />
<s:Button label='Button2' />
</local:MyComp>

Drag and drop item renderer(panel) within list

I have a spark List,its item renderer is a panel,and in the panel there are some components such as Textinput,now I want to drag and drop a panel within the List,how can I do that,could you pls show me the code,thanks.
The list in flex has a default drag and drop functionality. So basically all you need to do is to set 3 properties to true to your list:
dragMoveEnabled, dragEnabled and dropEnabled. So your list if you add it from mxml will look like this:
<s:List dataProvider="{yourDataProvider}" dragMoveEnabled="true" dragEnabled="true" dropEnabled="true" />
For more details about these 3 properties you can check the spark list documentation:
http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/spark/components/List.html#dragMoveEnabled
thanks for your help.Now I catch an error while draging the itemRenderer(my flex sdk is 4.5.1).
My list itemRenderer:
<?xml version="1.0" encoding="utf-8"?>
<s:ItemRenderer xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx"
width="100%" height="100%">
<fx:Script>
<![CDATA[
import mx.events.CloseEvent;
override public function set data(value:Object ) : void{
super.data = value;
}
protected function closeHandler(event:CloseEvent):void
{
//ToDo
}
]]>
</fx:Script>
<s:TitleWindow x="0" y="0" title="{data.label}"
width="100%" height="100%" creationPolicy="all"
skinClass="skin.titleWindowSkin"
close="closeHandler(event)">
<s:Label text="{data.value}"/>
<s:TextInput x="123" y="58" text="#{data.value}"
focusIn="parentDocument.owner.dragEnabled=false"
focusOut="parentDocument.owner.dragEnabled=true"/>
</s:TitleWindow>
</s:ItemRenderer>
While draging,catch an error like:
Error: Skin for DragProxy261.ListItemDragProxy260.DspDesktopItemRenderer262._DspDesktopItemRenderer_TitleWindow1.titleWindowSkin264.Group265.contents._titleWindowSkin_Group5.contentGroup._DspDesktopItemRenderer_TextInput1 cannot be found.
at spark.components.supportClasses::SkinnableComponent/attachSkin()[E:\dev\4.5.1\frameworks\projects\spark\src\spark\components\supportClasses\SkinnableComponent.as:698]

How to take screenshots of a Flex Spark VideoDisplay?

I want to build a component, where the user can play a video in a Flex Spark VideoDisplay. There will be a button and whenever the button is pressed, I want to save the current time of the VideoDisplay plus a screenshot. The screenshot needs to be someway saved, because I want to display all times and screenshots in a DataGrid (screenshots should appear when the user hovers a time in the DataGrid).
So, how can I take screenshots of the Spark VideoDisplay and save/display them?
You can take snapshots a few ways, this way just uses the ImageSnapshot class, but you could do it by manually drawing the bitmap of the video display if you'd like. Here's a sample:
Renderer
<?xml version="1.0" encoding="utf-8"?>
<s:ItemRenderer
xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx"
width="100" height="100" creationComplete="trace(data)">
<mx:Image source="{this.data}" width="100%" height="100%"/>
</s:ItemRenderer>
Sample App
<?xml version="1.0" encoding="utf-8"?>
<s:Application
xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx">
<fx:Script>
<![CDATA[
import mx.graphics.ImageSnapshot;
public function takeSnapshot():void
{
var snapshot:BitmapData = ImageSnapshot.captureBitmapData(videoDisplay);
var bitmap:Bitmap = new Bitmap(snapshot);
list.dataProvider.addItem(bitmap);
}
]]>
</fx:Script>
<s:layout>
<s:VerticalLayout horizontalAlign="center"/>
</s:layout>
<s:VideoDisplay id="videoDisplay"
source="video.mov"
width="400" height="300"/>
<s:Button id="button" click="takeSnapshot()"/>
<s:List id="list" horizontalCenter="0" width="100%" itemRenderer="SnapshotRenderer">
<s:dataProvider>
<mx:ArrayList/>
</s:dataProvider>
<s:layout>
<s:TileLayout/>
</s:layout>
</s:List>
</s:Application>
To accomplish exactly what you were describing (take snapshot and save snapshot), you could store those in an array in that takeSnapshot method, or you could loop through the list.dataProvider do get the bitmaps. Then you'd just need to pass them to a backend language (ruby, python, php...) to save.
Hope that helps,
Lance
use the JPEGEncoder in flex to convert it to bytearray, and then encode the byte array using the b64encoder as follow:
var jpg:JPEGEncoder = new JPEGEncoder();
var ba:ByteArray = jpg.encode(bitmapData);
var b64encoder:Base64Encoder = new Base64Encoder();
b64encoder.encodeBytes(ba);
var b64String:String = b64encoder.flush();
Now you can pass your b64String to your server via HTTP post method :)

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