Units provide the space where you can put GUI components and associated bitmap and font resources as well as all other project relevant members. As such, units can exist only at the root level of the project. Unit members are represented in Composer by following bricks:

From technical point of view, every unit member is associated with its own particular project file, Embedded Wizard automatically loads when you open the project and stores when you save the project. In accordance to other programming systems, the unit and its project file can be considered as a software module, a kind of library providing components. The unit project files are named after the unit name and have the file extension .EWU.

Each Embedded Wizard project can contain any arbitrary number of units, whereby the following few units are obligatory in every project, as they implement the essential core functionality of the Mosaic framework:

Every unit serves as a namespace for all included project members. This avoids potential name conflicts between homonymous members existing in different units and helps you to flexibly structure large projects. Dividing the project in several units helps also to simplify the development process in a team of several developers.

All members defined within a unit has a global character - they can be accessed from everywhere within your project. To address a member defined within a unit, you must always use its full name, which is composed of the unit name and the member name, both separated by :: (double colon). For example, the component Button defined within the unit Application is addressed by its full name Application::Button.

Adding a new unit member.

Per default, all newly added units store their associated project files directly in the directory of your project. With the attribute Directory you can explicitly specify another location where the unit will store its files.

When you rename a unit or specify a new unit directory, it is possible that the unit directory already contains a unit file matching the unit name. In such case Embedded Wizard will show the following warning in the Log window:

Now its up to you, how to resolve this conflict. Depending on your intention you have following two options:

Per default, a single unit is stored in its corresponding .EWU project file. With the attribute Split you can explicitly override this behavior, and force the particular unit to store its content as a set of files - one file for every project member contained within the unit. This is useful, when you edit the unit simultaneously together with other developers.

Every unit can contain any arbitrary number of other project members. To add a new or edit existing members open the unit in a new Composer page:

You can create a copy of an already existing unit member.

Please note, when you copy a unit member, the members included within the original unit are not copied. The new unit is empty. You can, however, select and copy the members between the both units in a separate step.

When you add a widget from the Gallery and the widget is implemented in a unit currently not included in your project, Embedded Wizard will automatically add the unit to your project. The following message appears in the Log window:

To add an already existing unit file to your project:

Shortly afterwards, a message will appear in the Log window asking you, whether Embedded Wizard should reload the content of the file:

Alternatively you can add existing units by conveniently drag-and-drop the original unit files (*.EWU) directly from the MS-Windows file explorer into a Composer containing the project main page. Accordingly, Embedded Wizard adds for every unit file a new unit member automatically. The unit members are already configured to refer to the location where the original unit files are found, so you don't need to specify the unit directory manually. To add new unit members by drag-and-drop do following:

Adding new unit members by drag-and-drop the original unit files from MS-Windows file explorer.

Shortly afterwards, a message will appear in the Log window asking you, whether Embedded Wizard should reload the content of the affected files:

If the content of a unit file has been modified by another Embedded Wizard instance, or an external application (e.g. after getting the latest file version from a SVN or GitHub system), a message will appear in the Log window asking you, whether Embedded Wizard should reload the content of the file:

The following table shows the complete list of attributes provided by the unit member:

Attribute name	Short description
Brick	Determines the position and the size of a unit member brick within the Composer window.
Description	Contains the description for the unit member.
Directory	Determines the directory for unit project files.
Split	Determines the storage format of the project files associated to a unit member.