Forms

Window is an empty frame to hold your object and it is the outermost boundary for a form. Block is a logical container that holds form objects such as data items and control buttons. There are two types of block: Data Block and Control Block. A Data Block is a link to your database information and holds database data. A Control Block holds information that has nothing to do with database. An item could be a database column or none database item. A canvas is a place to hold the objects. The four types of canvases are: Content, Stacked, Tab, and Toolbar. All can coexist within a single window. A content canvas is the basic background for all windows. A stacked canvas lays on top of the others. A tab canvas is the same as stacked canvases with handy �tabs� at the top. It can simply move from one canvas to another. A toolbar canvas contains push buttons giving users quick access such as horizontal canvas or vertical canvas.

Oracle tools are somehow follow object oriented methodology. Although they are not pure object oriented but there are not far from it either. Each item in the Oracle tools can be identified as an object. To manipulate an object, you use Property Palette. As you can see from now on, you can do much without property palette. A Property Palette contains object properties. The contents of the Property Palette are referred to as the �Property sheet� for the object. You use the Property Palette to modify object properties. To open the Property Palette of an object, go to the object and right click on the mouse button then select Property Palette. The Property Palette provides complete control over your objects. It contains the property list of an object. Remember that the properties of an object can be changed to control the behavior of the object. The Item properties such as Tooltip, Hint, and Display Hint automatically, will be used to provide item-level assistance for the client and can be changed only from property palette. A text item appearance can be modified by manipulating properties such as Justification, or Format Mask properties. For controlling the data within a text item or display item, you can use properties such as Calculation Mode, and Lowest and Highest value

On pervious Hands-On, your users only see the horizontal toolbar canvas instead of the Customer, Orders, and Items canvases. They have to drag the window in order to see their �Customer Order� application. They complain that it is cumbersome to drag the window in order to use the application. You have been assigned to fix this problem. The requirement from your client is: to make sure your layout was properly sized so your client doesn't need to drag or expand the window size.

See Figure 10.

Your tasks are:

1- Make sure the canvas was sized properly.

2- Run and test all user functional requirements.

FYou will learn how to: size your canvas, change the horizontal toolbar canvas, use tab canvas, use �object navigator,� use �Data Blocks,� use �Layout Editor,� use �Property Palette,� use �Run Form,� and �Execute Query.�

Figure 10

In the �Object Navigator� window, highlight Forms. Go to the Main menu and choose �File,� select �Open� to open an existing form (customer_orders_V07) in the folder.

Click on the �CUSTOMER_ORDERS_V07� form. The color will change to blue. Now, change the name and then save the Form name as version 08 (customer_orders_v08). This way the original form is untouched.

In the Main menu, choose the �Tools� sub-menu and select the �Layout Editor� option. In the Layout Editor window, make sure that the Canvas box contains �PB_BLOCK.� If not, click on the down arrow next to its box and select PB_BLOCK.

Now, you should have the PB_BLOCK canvas in the Layout Editor window. In the Object Navigator window, expand the Canvases item and select the PB_BLOCK canvas. Notice that in the Layout Editor window, the canvas gets eight handlers. You can use these handlers to expand the size of an object.

Click on the middle down handler to expand the size of canvas. Make sure that you drag the black line and let the white line stays. After you reach to a suitable size, release your mouse. The white line is the border of the "horizontal toolbar canvas." And the black line is the border of the content canvas.

Run the application

If the window was not sized enough, you can close the Runtime Form window and repeat the above steps until you are happy.

Run the application again and check the appearance of the application.

Questions:

Q: Describe a Window in the Form Module.

Q: The properties of an object can be changed to control the behavior of the _____.

Q: What is a Data Block in the Form Module?

Q: How do you resize an object in the Layout Editor?

Q: How do you move an object or a group of objects in the Layout Editor?

Q: What are the handlers in a selected object?

Q: On pervious Hands-On, your users only see the horizontal toolbar canvas instead of the Customer, Orders, and Items canvases. They have to drag the window in order to see their �Customer Order� application. They complain that it is cumbersome to drag the window in order to use the application. You have been assigned to fix this problem. The requirement from your client is: to make sure your layout was properly sized so your client doesn't need to drag or expand the window size.

See Figure 10.

Your tasks are:

1- Make sure the canvas was sized properly.

2- Run and test all user functional requirements.