# The VL Docking Framework for JFC "Swing" applications.

## Goals.

The VLSolutions Docking Framework provides a means to add docking capabilities into a Swing application with minor modification of the components hierarchy (only decoration of existing components and containers and adding of a new root container).

## Audience.

This javadoc is targetted to :

- API Users : developpers of "User Applications"
- API Extenders : developpers that want to extend the framework, add new kinds of containers, or change the look and feel of existing ones.

You will find in this documentation references of those targets, indicating you if you have to read such document or not, depending on your goals (developping a "User Application" or extending the API).

## For API Users

### Basic Description

The VL Docking Framework is a set of Swing Components that is used to enhance any Swing Application by providing Docking capabilities to user components :

A user component can be any Swing JComponent (usualy a JPanel or a JScrollPane).

Docking functions are built upon the following classes :

- `DockingDesktop` : the root container of a docking-enabled application
- `Dockable` : an interface implemented (usually) by components that need docking capabilities.
- `DockableContainer`s : specialized containers with drag and drop extensions (come in two flavors, SingleDockableContainer and TabbedDockabeContainer).
- `DockKey` : a JavaBeans object fully describing the dockable (use for save/load, and for DockableContainers customization) : name, icon, tooltip, docking features.

### The `DockingDesktop` class.

There is usually only one DockingDesktop associated to a Window.

For developpers used to `JInternalFrame` API, the DockingDesktop is equivalent to the `JDesktopPane` : a layered pane capable of managing and displaying multiple components, with overlapping when needed.

The desktop is composed of :

- 4 auto-hide zones (on borders ) displaying buttons that are used to activate or hide their `Dockable`.
- a central zone, for visible Dockables (or "docked" components).

The central zone contains a `DockableContainer` that can be recursively splitted in two (horizontally or vertically) to add more DockableContainers. Each split acts as a JSplitPane, and can be resized by the end-user or with the API.

### The `Dockable` interface

The `Dockable` is implemented by dockable component providers or, simply by components that want to benefit of the docking features.

If you already have a working application (without docking) and want to use the docking framework, take your GUI major components, have them implement the Dockable interface (only 2 methods) and you will be able to add them to the docking desktop.

Alternatively, you can use DockablePanel which is a JPanel container implementing Dockable.

### The `DockableContainer`, `SingleDockableContainer` and `TabbedDockableContainer` interfaces.

These interfaces are implemented by containers of Dockables. Usually you will not interact with them (except if you want to extend the framework).

### The `DockKey` class

This one is important because it fully describes the Docking presentation of your dockables, and their behaviour.

A DockKey is used in 3 situations :

- the `DockingDesktop` needs a unique key to identify a dockable (for read/write operations)
- the `DockableContainer` displaying a `Dockable` wants information about the dockable : a name, an icon, ...
- and finally, the DockingDesktop and DockableContainer only allow docking features associated to that DockKey (maximizeable, closeable, hidable...).

So keep in mind that each dockable must have a unique DockKey (it's a kind of primary key) and that the key, as a javabean, is used to decorate the dockable container.

Listeners : most DockKey properties are bound, and changing their value will have an immediate effect on the DockingDesktop : for example, you can change the icon property of a key and it will be propagated to the DockableContainer's title bar of its dockable.

## Getting Started

It's easy, just follow the steps below, or have a look at the tutorial on www.vlsolutions.com/en/documention/docking/tutorial.

### Creating a small sample application :

Here is a working code showing a simple frame with dockable buttons.

    import com.vlsolutions.swing.docking.*;
    import javax.swing.*;
    import java.awt.*;

    public class DemoFrame extends JFrame {
      // our docking desktop
      DockingDesktop desk = new DockingDesktop();

      public DemoFrame(){
        setDefaultCloseOperation(DISPOSE_ON_CLOSE);
        getContentPane().add(desk);

        // first, create 4 dockable buttons (inner class below)
        DockableButton button1 = new DockableButton("Dockable 1");
        DockableButton button2 = new DockableButton("Dockable 2");
        DockableButton button3 = new DockableButton("Dockable 3");
        DockableButton button4 = new DockableButton("Dockable 4");
        // first button at center
        desk.addDockable(button1);

        // second and third button splitted vertically on the left of center
        // first parameter is the "reference", second is the added dockable
        desk.split(button1, button2, DockingConstants.SPLIT_LEFT);
        desk.split(button2, button3, DockingConstants.SPLIT_BOTTOM);

        // add the fourth button as a tab on the 3rd :
        desk.createTab(button3, button4, 1);

        SwingUtilities.invokeLater(
            new Runnable() {
          public void run() {
            setSize(800,600);
            validate();
            setVisible(true); // realize on the event dispatch thread

          }
        });
      }
      public static void main(String [] args){
        new DemoFrame();
      }

      // our basic dockable object
      class DockableButton extends JButton implements Dockable {
         DockKey key;
         public DockableButton(String label){
            super(label);
            this.key = new DockKey(label); // most simple dockkey constructor
            setPreferredSize(new Dimension(200,200));
         }

        public DockKey getDockKey() {
          return key;
        }

        public Component getComponent() {
          return this;
        }
      }
    }

But of course, there's more in the docking framework than this. For example you can also :

- hide a component on a border
- attract user attention by a blinking dockable title
- adjust the width and height of the dockables
- read and write a desktop configuration from/to an XML stream
- ...

You can read more about these features in the tutorial on www.vlsolutions.com/en/documention/docking/tutorial.

## Browsing the API

The subset of classes of this package needed to understand and use the Docking Framework is limited to the following classes :

- DockingPanel : the panel that contains the users components is also the main interface to docking functions.
- Dockable : the interface implemented by dockable objects
- DockKey : the key of a Dockable, an object that describes a user component (icon, text, tooltip)

## Extending the API

This API has been developed with extension in mind.

To Fully understand its principles, you will have to browse the entire javadoc and read the API extension tutorial on www.vlsolutions.com.