the way to create object now is like this:

we’re defining here a static function called getInstance which calls the constructor only if servicesLocator object is null or not initialized already. A sinlgeton class is particularly of high use for HTTPService object as it allows single point of handling all the requests in this way.

Recently in one of my projects, I’d to use the IViewCursor to search the XMLListCollection and faced some problems initially but implemented it successfully after doing some research. I’m posting the same example (-) the actual database contents…i’ll use sample XML files for the purpose of this example.

The scenario for which i’ve implemented this thing is as follows:

I’ve three tables users,courses and privileges. The users and courses tables contains the details of the existing courses and users and the privileges table contains the course–>user mappings and access levels.

Now in flex, i’m using datagrid to show the privileges…and another form to create new priviliges. This form contains
two list boxes for users and courses and checkboxes for each privilege.

So when the admin of my application selects a course and user and if that user has already has some privileges over that course, those privileges have to be shown by autoselcting the corresponding checkboxes.

So to match the selected user and course with the existing privileges, i’m using IViewCursor. but the IviewCursor’s findAny() method returns true if either course or user is found in the privileges list which is not exactly what i’m expecting…i.e return true only if a row contains both the selected user and course.

And here is the sample of the application:

Right Click/Click on the view source button to view the source of this application.

Now some explanation:

The application contains a datagrid which shows the privileges of a particular user on a particular course and two list boxes showing all the available courses and users. When you select a user and a course, an Alert box appears if the selected user has some priviliges allocated to her on the selected course.

To do this, first of all i’ve stored my data in 3 XML files

• Privileges.xml contains the details of which user has what priviges on a course
• Course.xml contains details of  courses available
• users.xml contains details of all users available

There is an XMLListCollection named privilegesModel in to which the privileges.xml is loaded. Once it is loaded, i’ve sorted the collection on the two criteria on which i’m going to search i.e user name and the course name like this:

Remember

• you must sort the XmlListCollection if you want to user IViewCursor’s methods on it…otherwise flash will throw a runtime error saying that the collection is not sorted.
• The sort must be on all the fields on which you’re going to search later. i.e here i’m searching for a row with both the coursename and user name…so, i must sort XMLListCollection on both username and coursename fields. If i sort it on just course name or user name and later search on both criteria, flex will return true for for any row with containing just the single field on which i’ve sorted … let’s assume that i’ve sorted on just the username liket this:

and then i search the collection usign IViewCursor’s findAny method like this:

then flex will show found Alert when ever you select a user present in the collection and any course…still confused?? watch this example:

http://ravimarella.com/XmlListCollection/XMLListCollectionSearch.html

So you must sort the collection on all the fields for which you’re going to search otherwise the results will not be as expected.

Hope that post helps someone. Leave a comment if anypart of the post is still confusing..

Happy Flexing…

Ravi.

At first i thought of giving a custom path value to the viewSourceURL property of the Application tag like this:

and just export the release build without selecting the view source option. But the problem with this is Flex Builder automatically deletes the viewSourceURL variable and its value once it publishes the release build. So my options are to place the above code intact and just the debug version of the swf. But the debug version contain lot of unnecessary info and adds up to the file size ultimately. So this is the solution i came up with:

1. Add a new Right Click Context Menu item on the application’s CreationComplete event like this:

What this will do is add a new menuitem to the menu that appears when you Righ Click or Ctrl_+Click on Mac called “View Source” and up on clicking this menu item navigates to the URL mentioned. The menuitem name can be named ofcourse as anything you want.

2. Export the release build with viewsource option enabled. This step is just to gather the source files. You can skip this step and select the source files your self and place them in a single folder. I prefer the first method as flex published the index.html and uses a clean interface to navigate through and download different items of your source.

3. Now, you can edit the source code exported to remove the viewSourceURL option just for the sake of your users or keep it intact if you dont prefer to take the extra step and let your users see the extra ViewSource option which is not the one that you are actually using. Note that flex renames creates your mxml files as .mxml.html files…so to remove that ViewSourceURL option, just open the main application mxml file in any text editor and remove the code pertaining to the ViewSourceURL.

Now just upload the source code folder contents in the exactly same URL as mentioned above by you.

Thats it…now you are ready with a Custom and absolute path for your Source code.

Here is sample that i’ve done:

Right Click any where on the application and click View Source option to see the source…

REMEMBER, you’ve to export the release build twice…first time with the source code export option selected and second time without the sourcecode option so that the default viewsource option wont show up on right click…

Happy flexing..

cheers,

ravi.

just rollover any of the listbox items and it will show the index of that item. So once you’ve the index, i guess you can do any custom label operations.

Here is the source code for the above example:

Here is the post which explains a much simpler way to create tooltips but you cannot custom place these tooltips:

http://raghuonflex.wordpress.com/2007/09/19/tooltips-for-combobox-items-or-list-items/

This is a duplicate of this post by neil and full credit goes to him. I’ve posted it again coz the original post has some problems with flash embedding because of which the application is not working from the embedded swf.