Macromedia flash media server 2-client-side actionscript language reference for flash media server 2 Benutzerhandbuch

SharedObject class

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Assign an owner

  A more sophisticated strategy is to define a single client as the owner of a 

property in a shared object for a limited period of time. You might write server code to create 
a “lock” object, where a client can request ownership of a slot. If the server reports that the 
request was successful, the client knows that it will be the only client changing the data in the 
shared object. 

Notify the client

  When the server rejects a client-requested change to a property of the 

shared object, the 

 event handler notifies the client that the change 

was rejected. Thus, an application can provide a user interface to let a user resolve the conflict. 
This technique works best if data is changed infrequently, as in a shared address book. If a 
synchronization conflict occurs, the user can decide whether to accept or reject the change.

Accept some changes and reject others

  Some applications can accept changes on a “first 

come, first served” basis. This works best when users can resolve conflicts by reapplying a 
change if someone else’s change preceded theirs.

Local disk space considerations

You can choose to make remote shared objects persistent on the client, the server, or both. 
(Local shared objects are always persistent on the client, up to available memory and disk 
space.) 

By default, Flash can save locally persistent remote shared objects up to 100K in size. When 
you try to save a larger object, Flash Player displays the Local Storage dialog box, which lets 
the user allow or deny local storage for the domain that is requesting access. (Make sure your 
Stage size is at least 215 by 138 pixels; this is the minimum size Flash requires to display the 
dialog box.)

If the user selects Allow, the object is saved and 

 is invoked with a 

code

 property of 

SharedObject.Flush.Success

. If the user selects Deny, the object is not 

saved and 

 is invoked with a 

code

 property of 

SharedObject.Flush.Failed

.

The user can also specify permanent local storage settings for a particular domain by right-
clicking (Windows) or Control-clicking (Macintosh) while a SWF file is playing, and then 
selecting Settings and clicking Advanced. From the Settings Manager list, the user selects 
Local Storage Settings to open the Local Storage Settings panel. 

You can’t use ActionScript to specify local storage settings for a user, but you can display the 
Local Storage dialog box for the user by using 

System.showSettings(1)

.