Previous User Interface Programming: Using the IDL GUIBuilder Next

Using the Tree Editor

To define a tree widget hierarchy for your interface, use the Tree Editor, shown in the following figure. This dialog allows you to define tree nodes and folders, menus, menu items, submenu titles, and submenus, and all their associated event procedures.

Figure 3-11: Tree Editor Dialog

Figure 3-11: Tree Editor Dialog

To create a tree hierarchy, do the following:

  1. Add a tree widget to your interface, right-click on the widget, and choose Edit Tree. A new tree widget is created, beginning with the root node of the tree.

    2.  

  2. Click Insert to add a node to the tree. Nodes are added as leaf nodes below whichever node is currently selected. Inserting a node below an existing leaf node turns the existing leaf node into a branch node (that is, a folder). You can also turn a leaf node into a branch node by selecting the node and clicking the Folder checkbox.

    3.  

  3. Modify the Caption and Name fields for each node as desired. The value of the Caption field will be come the VALUE of the tree widget; this string is used as the text label when the widget is displayed. The value of the Name field will become the variable name of the variable that holds the tree widget's widget ID.

    4.  

  4. To delete a node from the hierarchy, select the node and click Delete. Any nodes or that have the selected node as their parent will also be deleted.

    5.  

  5. Expand and collapse nodes within the editor by clicking on the plus and minus symbols to the left of the branch nodes.

    6.  

  6. Rearrange the nodes and branches as desired by dragging and dropping the nodes' captions or icons.

    7.  

  7. Click OK to save your changes to the tree widget hierarchy, or Cancel to abandon your changes.

  IDL Online Help (March 06, 2007)