Calling an implemented method from an external class.

Hey guys...
I'm writing a package to be put into a program I'm writing for a project (for Uni), but I also want to use the package in other programs.
Basically, the package will return a JScrollPane that can be put into any JFrame or JPanel or whatever.
It draws boxes on the JScrollPane in different colours and locations depending on what information is passed to it (kind of like iCal or Microsoft Outlook Calendar), and is to be used for a Resource Allocation Program that requires drag and drop of boxes for moving bookings around etc.
http://www.pixel2.com.au/ethos/class_diagram.png
This is a copy of the class diagram for the relevant classes. ViewFrame is the class that instantiates the JScrollPane (AllocationTable). It implements the AllocationInterface to implement methods such as moveAllocation() newAllocation() etc.
BookingPanel is the content pane for the JScrollPane. AllocatedBox is the individual bookings, or boxes that are painted onto the BookingPanel.
BookingPanel implements ActionListener, MouseListener and MouseMotionListener, which enables drag and drop functionality.
What I want to do, is when mouseReleased() is called by dropping a box, call the method moveAllocation() in ViewFrame to make the changes to the database to move the booking around.
I don't know how to access that from BookingPanel as the name of ViewFrame will change obviously for different programs.
If you could help me out, that would be great!
If you need anything else explained, please let me know.
Thanks,
Ryan.

LeRyan wrote:
Hey guys...
I'm writing a package to be put into a program I'm writing for a project (for Uni), but I also want to use the package in other programs.
Basically, the package will return a JScrollPane that can be put into any JFrame or JPanel or whatever.I think you have some terminology issues that might stand in your way of getting help or understanding the issues. A Package is a grouping of classes, so a package doesn't return anything...
It draws boxes on the JScrollPane in different colours and locations depending on what information is passed to it (kind of like iCal or Microsoft Outlook Calendar), and is to be used for a Resource Allocation Program that requires drag and drop of boxes for moving bookings around etc.So from your description of the function of this thing, I think you mean a class - some sort of JComponent?
>
http://www.pixel2.com.au/ethos/class_diagram.png
This is a copy of the class diagram for the relevant classes. ViewFrame is the class that instantiates the JScrollPane (AllocationTable). It implements the AllocationInterface to implement methods such as moveAllocation() newAllocation() etc.
BookingPanel is the content pane for the JScrollPane. AllocatedBox is the individual bookings, or boxes that are painted onto the BookingPanel.
BookingPanel implements ActionListener, MouseListener and MouseMotionListener, which enables drag and drop functionality.
What I want to do, is when mouseReleased() is called by dropping a box, call the method moveAllocation() in ViewFrame to make the changes to the database to move the booking around.
I don't know how to access that from BookingPanel as the name of ViewFrame will change obviously for different programs.
If I follow, and I am not sure that I do - you want a reference to the ViewFrame in the BookingPanel. So either on construction of the BookingPanel via a parameter in the constructor, or as a separate step via a setter, place a reference to the ViewFrame in BookingPanel. Then when you call mouseReleased you can call moveAllocation through that reference.
If you could help me out, that would be great!
If you need anything else explained, please let me know.
Thanks,
Ryan.

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