Defining and Using Eclipse Folders in your Composite Applications
If you have been working with Eclipse for any period of time then you are more than likely familiar with the concept of folders within a perspective layout. Folders in eclipse provide the ability to render Eclipse views in a "stacked" appearance. Folders can be positioned anywhere a view can. This screen shot below shows 3 eclipse views contained in a folder. Each of the views is accessible by clicking on the tab displaying the view title.
When building your composite application with the Composite Application Editor tool (CAE), you can drag components (views) from the pallete to your application page. You can create a folder easily by dragging multiple components on top of one another and you will see the multiple tabs show up as such:
When you drag components onto the page and create a folder, the folder has a unique ID associated with it. If you right click on one of the views in the folder shown above in the CAE, you will be able to examine the advanced properties for the component and see the folder defined in the component topology under the preference name "com.ibm.rcp.folder":
Now that you have a folder defined, it is possible that your composite application will programmatically open other views which are not defined in the topology of your composite application. This means that you have not added the component (view) to the definition of your composite application. By default in Eclipse, when you open a view programmatically, and there is no placeholder defined for it, the view opens in the bottom right of the perspective. However, through the use of placeholders it is possible to configure your app to have a "Default Folder", for all views which are not defined at design time to open in. For example, if we wanted to have all views open in the folder shown in the screen shot above, we would add a preference value to the PAGE which contains the folder as follows. Select the PAGE which you wish to set the default folder for, then right click on it and select edit page properties and click the advanced tab. Add the parameter as shown here:
Now if one of your components is built to programmatically open other eclipse views that are not defined within the layout of the composite application, they will open up in this folder. This is useful for applications that have a main editor area where each time a new document is opened it is stacked on top of its predecessor. I hope you find this useful. Please let me know if you have questions.