The Drip Wire : Developer News
Reporting on The Droplets SDK - a distributed GUI toolkit • component-based UIs • server side programming
March 1, 2002
Volume 1, Issue 6

Extra! Extra! Dynamic Graphing!
Wireless Client! More!

We've added a whole slew of major new features for developers in Droplets 2.2, including:

Dynamic Graphing Capabilities
Wireless Client
Solaris 8 Server
Calendaring
Application Frames
Enhanced Desktop Alerting
Double-byte Font Characters


Dynamic Graphing Capabilities
Droplets 2.2 includes a graphing component in the API for the creation of interactive bar and line graphs that can be updated in real-time on either the client or server. Droplets graphing gives you significant bandwidth savings, as lightweight graph descriptions are sent instead of image files, making it possible for Droplets graphs to respond to clicks, provide tooltips on graph elements and support drag-and-drop editing of graph values.

Wireless Client
Droplets has partnered with SavaJe Technologies to bring you a wireless client that can serve your Droplets to wireless devices running the SavaJe OS as well as desktops — with no additional development required. An additional Personal Java wireless client is in the works and will be available to the public shortly.

Solaris 8 Server
The Droplets Server for Solaris 8 has been released and is ready for your commercial Droplets deployments. Contact Droplets today to find out more about running Droplets from your Solaris environment.

Calendaring
The new Droplets Calendar component allows you to easily implement shared calendaring in your Droplets applications. Just insert the calendar into your GUI and wire events to its fields.

Application Frames
The Droplets API now features a new type of window, the Frame. Frames and sub-frames allow you to create applications in which windows and sub-windows can be maximized and minimized independently of one another, creating an environment that's even closer to the desktop experience than ever before.

Enhanced Desktop Alerting
Droplets Platform enhancements now allow you to create desktop alert dialogs from which you can directly launch a Droplet.

Double-byte Font Characters
Droplets goes multi-lingual. You can now present any character in any language supported by the Unicode double-byte font character standard.

Developer Tip
Using the Tree Component

A tree can be created using one of two constructors in the Droplets API's Tree class. In either case, tree creation must be done within your application Frame's addAllComponents() method:

  1. Tree (LayoutPlacement p, Window window)
    This constructor does not associate a set of images with the tree. Simply create a new Tree and assign it a layout placement (gridx, gridy, gridwidth, gridheight).

  2. Tree (LayoutPlacement p, java.lang.String imageFile, int iconWidth, Window window)
    imageFile should be a GIF or JPEG which holds the tree's images, organized horizontally, all of equal size     (as you'll see below, these are then called from left to right using 0, 1, 2, etc.). iconWidth indicates the width in pixels of each image.

Tree nodes should be built in your Frame's start() method:

  1. Call the tree's start method within the Window's start() method.

  2. Call the tree's getRoot() method to get the root node.

  3. Add nodes to the root by calling its add() method.

    start()
    {
       myTree.start();
        TreeNode root = myTree.getRoot();
       root.add(new TreeNode ("child1"));

  4. To add sub-nodes onto non-root nodes, create an instance of the parent node, add the sub-node to it and then add the parent to the root node.

Images are associated with nodes during construction. This can be done in one of two ways:

  1. Choose one of the TreeNode constructors which includes an imageIndex parameter:

    TreeNode child = new TreeNode("child",2);

    This must be done explicitly for each node.

  2. After creating the node, you can alternately call the node's setImageIndex() method:

    TreeNode child = new TreeNode("child"); 
    child.setImageIndex(2);

We'll continue to make Droplets even better and tell you about it from time to time. Meanwhile, please give us your feedback and check back with us at www.droplets.com.

Best regards,
The Droplets Team