• Applications
  An application consist of a series of screens.
• Screens
  A screens displays information to the user, optionally gathers user input and optionally executes a series of actions when the user moves to the next screen.
• Actions
  An action usually makes a modification to the installation.

• an action, a screen or an application. Actions and screens are made available by install4j or are contributed by an installed extension. A registry dialog will be shown where you can select the desired screen or action. When adding an application, the application template dialog is displayed.
• an action or a screen that is contained in your custom code. New types of reusable actions or screens can be developed with the install4j API. In your custom code configuration you can specify code locations that are scanned for suitable classes. A class selector will be shown where you can select the desired class.
• an action group or a screen group. The new group is initially empty. Note that you can also create groups directly from a selection in the tree of installer elements (see below).

• Applications
  are added at the top level.
• Screens and screen groups
  can be added to applications or screen groups.
• Actions and action groups
  can be added to screens or action groups.

If you select a single installer element in the tree of installer elements, you can edit its properties on the right side. Selecting multiple installer elements is possible on the same tree level, i.e. all selected elements have to be siblings in the tree.

When the configuration area is focused, you can transfer the focus back to the tree of installer elements with the keyboard by pressing ALT-F1.

The tree of installer elements provides the following actions in the toolbar on the right that operate on the current selection. You can also access these actions from the context menu or use the associated keyboard shortcuts.

• Delete
  All selected installer elements will be deleted after a confirmation dialog when invoking the  Delete action. The deleted installer elements cannot be restored.
• Rename
  After you add a installer element, the tree of installer elements shows it with its default name. This is often enough, however, if you have multiple instances of the same installer element alongside, a custom name makes it easier to distinguish these instances. You can assign a custom name to each installer element with the  Rename action. The default name is still displayed in brackets after the custom name. To revert to the default, just enter an empty custom name in the rename dialog.
• Comment
  By default, installer elements have no comments associated with them. You can add comments to selected installer elements with the  Add Comments action. When a comment is added, the affected installer elements will receive a "Comments" tab. After adding a comment to a single installer element, the comment area is focused automatically. Likewise, you can remove comments from one or more installer elements with the Remove Comments action.

  In order to visit all comments, you can use the Show next comment and Show previous comment actions. These actions will focus the comment area automatically and wrap around if no further comments can be found.

• Disable
  In order to "comment out" installer elements, you can use the  Disable action. The configuration of the disabled installer elements will not be displayed, their entries in the tree of installer elements will be shown in gray and they will not be checked for errors when the project is built.
• Copy and paste
  install4j offers an inter-process clipboard for installer elements. You can  Cut or  Copy installer elements to the clipboard and  Paste them in the same or a different instance of install4j. Note that references to launchers or references to files in the distribution tree might not be valid after pasting to a different project.

  Pasted installer elements are appended to the end of the same level that would be chosen if you added installer elements of that type. Sequence restrictions with respect to the already present installer elements may force a different order.

• Reorder
  If your selection is a single contiguous interval, you can move the entire block  up or  down in the list. The selection can only be moved on the same level with the reorder actions. To move the selection to a different parent, you can cut and paste it (see above).

• Group
  You can create a screen group or an action group from the selected installer elements with the  Create Group action. The new group will be inserted in place of the selected installer elements.

  You can dissolve a group with the Dissolve Group action. This action is only enabled if the selection consists of a single screen group or action group. The elements contained in the group will be inserted in place of the group. Nested groups will not be dissolved.

• Link
  You can reuse screens and actions by linking to a single definition. This is particularly useful if you define a installer maintenance application that should repeat parts of the installer, such as a number of forms that query the user for initial values to set up your application. Also, links are the only way to integrate screens and actions from the installer or uninstaller merged project into the main project.

  In order to link to a screen, action, screen group or action group, you click on the add button and select Add Link Into from the popup menu. The first entry in that popup menu is always "This project" for links into the current project. If you have set up merged projects, then you get an entry for each merged project. The configuration area of a link will only contain a button that selects the original definition in the tree of installer elements. For merged projects, the merged project is opened in a new window, unless it is already open.

  Another way to add a link into the same project is to select the installer element and invoke the  Copy Link action. Then you navigate to the installer element where the link should be inserted and invoke the Paste Link action.

  For links into the same project, install4j ensures that there are no broken links in the tree of installer elements. When you delete an installer element, all links to it will be deleted as well. If that is the case, the deletion message will tell you how many links are about to be deleted. Links into merged projects may be broken, this condition is shown in in the configuration pane.

When using the install4j API, you reference installer elements with IDs. You can show IDs in the tree of installer elements by activating the  Show IDs button on the lower right side of the tree of installer elements. The automatically generated numerical IDs are then shown in brackets. The selection will be remembered across restarts of install4j.