Message mechanism

PowerServer Mobile and PowerBuilder uses different message mechanisms which have different message queue. The message mechanism that PowerServer Mobile uses is mostly the mobile OS' mechanism which has the following differences from PowerBuilder's:

  • The operation and event handling is concurrent.

    Suppose the Click event of a CommandButton executes a complex loop. The user clicks this button and then during the execution of the first click event, the user clicks the other controls in the window. In PowerBuilder, the other clicks will not be triggered even though the first click event is finished, while in PowerServer Mobile, the other clicks will be handled after the first click event is ended.

  • The event handling is blocking.

    For example, the Click event of a CommandButton pops up a message box or executes a complex loop, the other events such as UI refresh (if StaticText is updated by the loop, it will not be refreshed immediately), Timer events etc. will not be handled.

  • The event handling is asynchronous.

    Suppose the user right clicks a control or a window to display the PopMenu, and then operates on the menu item. In PowerBuilder, the sequence is pop up the menu, execute the menu item events, and then execute the remaining scripts in the RightClick event. While in PowerServer Mobile, the sequence is pop up the menu, execute the remaining scripts in the RightClick event, and then execute the menu item events.