Concept : Understanding Forms 
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[edit] Description
In Bungee Connect, a form is a part of the View and acts as the primary element in your application interface. You lay out your UI on a form, and it is in the context of a form that you bind UI elements (controls) to data structures and functionality (the Model).
A form is first and foremost a container. A form can contain both common controls (such as a Button or a List) and [ontainer controls (such as BulletinBoard and Grid). Because a form is a container, you can create very sophisticated user interfaces by embedding container controls within other container controls like Russian dolls. You can also reuse a form in the context of another form—for example, you can embed one form directly within another (by dragging and dropping). In addition, you can display the visual interface of one class within the context of the visual interface of another class on an as-needed basis dynamically, at runtime. For more information on this topic see the documentation for the DynamicForm and FormList controls.
Whereas in some systems a form is a standalone class, in Bungee Connect, you can add a form to your project only as a member of a class. A single class can have n forms. The purpose of a form is to enable you to construct a visual representation (the View or UI) of all or a portion of that class (the Model). A form is distinctly a View element and enforces (in conjunction with interfaces and adapters) a proper separation between the View and the Model. The fact that a form is a member of a class keeps the visual presentation of that class from being bound in a messy or "spaghetti code" way to any other portion of the Model, or indeed to some other portion of the View. The close association of a form with its parent class helps to maintain a clean separation between the View and the Model throughout your application.
[edit] Changing Form Container Styles
The default parent Container Type for a form is a Grid. Grid is one of six available layout options. Use the Container Type property to change from one layout option to another.
[edit] Embedding Containers
The container controls can be embedded one inside of another. For example, if you leave the parent Container Type of the form set to Grid, you can drag (from the Toolbar under Containers) a BulletinBoard container into the top left cell of the parent Grid. You can now drag other controls onto the embedded BulletinBoard. The screen shot below shows a Button control being dragged onto an embedded BulletinBoard. Because the embedded container is a BulletinBoard, there is a Tooltip showing the x and y coordinates of the mouse position as the button is placed.
As another example, if you set the parent Container Type of the form to BulletinBoard, you can drag (from the Toolbar under Containers) a Grid onto the BulletinBoard.
You can nest several embedded containers. The following screen shot shows four nested Grid containers each inside of their respective parent Grids.
[edit] Grid Container
The most popular and flexible container control is the Grid. To select the top level Grid on a new form, click in the form (or in the dark area outside the form). With the Grid selected, two types of Grid-editing controls appear on the rulers. The green buttons are the Edit Row and Edit Column buttons and let you add and delete rows and columns, and change other settings. The gray row and column resize handles are for resizing the rows and columns.
A Grid can be customized by:
- Editing row or column settings
- Inserting or Removing rows or columns
- Setting whether the row or column is Stretchable
- Setting whether the row or column is Locked
- Adding a Separator between columns
- Setting the vertical and horizontal alignment for the row or column
- Resize Rows or Columns
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Removing and Restoring Grid Walls
See Editing a Form for more information.
[edit] See Also
Editing a Form
Adding a Form to a Class
Embedding a Form within a Form Using Drag and Drop
Understanding Copy and Paste
Using Copy and Paste
Binding a Control to an Object
DynamicForm
FormList
