1 Chapter 6: Creating Oracle Data Block Forms

2 Forms  Application with a graphical user interface that looks like a paper form  Used to insert, update, delete and view database data

3 Primary Form Uses  Viewing/retrieving records  Inserting/updating/deleting records  Counting the number of records a query will retrieve

4 Data Block Forms  Form associated with a specific Oracle database table  System automatically creates:  Text fields associated with table fields  Programs for inserting, modifying, deleting, and viewing data records

5 Data Block Form

6 Form Modes Normal You can view records and sequentially step through records Enter Query You can enter search parameters in form fields and then retrieve the associated records To place the form in Enter Query mode, click the Enter Query button

7 Inserting New Records In Normal mode, click the Insert Record button to insert a new blank record Type the data values in the form fields Click the Save button to save the values in the database

8 Retrieving Records Click the Enter Query button to place the form in Enter Query mode Type a search condition Click the Execute Query button to retrieve selected records If you click, do not enter a search condition, and then click, all table records will be retrieved

9 Form Search Types Exact search: only retrieves records that exactly match the entered search condition Restricted search: retrieves records that fall within a range of values

10 Restricted Search Operators  _: wildcard replacing a single character  %: wildcard replacing multiple characters  >, <: greater than, less than  >=, <=: greater than or equal to, less than or equal to  <> or !=: not equal to

11 Scrolling Through Retrieved Records To view the next record, click the Next Record button To view the previous record, click the Previous Record button

12 Updating and Deleting Records Retrieve the record to be updated or deleted To update, change the data value and click the Save button To delete, click the Remove Record button

13 Data Block Form File Types .fmb  Form design file, used by form programmer in Form Builder .fmx  Form executable file, run by form users

14 Form Components  Form module: form application  Form window  Title bar on top  Horizontal and vertical scrollbars  Can be resized, maximized, minimized

15 Form Components  Canvas  Surface that displays form items  Block  Object that contains form items  Form items  Command buttons, radio (option) buttons, text items  Items in the same block can appear on different canvases

16 Form Components Name Cash Check Credit Card Window Canvas Block of items

17 Creating a Data Block Form  Steps: 1. Create the data block using the Data Block Wizard 2. Create the form layout using the Layout Wizard

18 Data Block Wizard  Welcome page  Type page  Select table or view on which to base the block source  Table page  Select table associated with form  Finish page  Option to use the Layout Wizard to automate creating the layout

19 Layout Wizard  Canvas page  Select the canvas where the block is displayed  Data Block page  Select the fields that are displayed on the layout  Items page  Specify the column labels, heights and widths  Style page  Specify to create a form- or tabular-style layout

20 Layout Styles  Form style  One record appears on the form at a time  Tabular style  Multiple records display on the form in a table

21 Form Builder Wizards Are Re-entrant  You can select a block or layout, then re-enter it and modify its properties using the Wizard  A Wizard is in re-entrant mode when its pages appear as tabs

22 Form Builder Object Navigator Window  Shows form objects  Allows developer to access form objects  Object Navigator has 2 views  Ownership view: shows form objects as a flat list  Visual view: hierarchical relationships between objects

23 Guidelines For Configuring Form Windows 1. Change the window title 2. Allow user to minimize the window 3. Do not allow the user to maximize the window 4. Do not allow the user to resize the window 5. Include horizontal and vertical scrollbars if items appear beyond window boundaries 6. Make the form window fill the Forms Runtime window

24 Configuring Form Windows Window Title Minimize/ Maximize buttons Window size

25 Creating a Form Based on a Database View View can be derived from multiple database tables Form based on a view allows you to display data from multiple tables Form cannot be used to insert, update, or delete data

26 Modifying Form Properties Every form object has a Property Palette that allows you to configure form properties Property Nodes Property List

27 Intersection Property Palette Used to change property of several items to the same value Intersection/Union button appears as Name appears as *****

28 Frame Properties Update Layout Automatically Frame items are automatically repositioned based on their order in the Data Blocks list when you move or resize a frame, or modify the form layout using the Layout Wizard in reentrant mode Manually Items are automatically when layout is modified in Layout Wizard in reentrant mode Items are not repositioned if you move or resize the frame Locked Items are never automatically repositioned

29  Data block forms can display data from multiple tables that have a master-detail relationship  Master record has multiple related detail records  Examples:  One ITEM record has multiple related INVENTORY records  One CUSTOMER might have multiple CUST_ORDER records Multiple-Table Forms

30 Master block Detail block Master-Detail Forms

31 Creating a Master-Detail Form Create the master block first Specify the relationship on the Data Block Wizard Master-Detail page of the detail block

32  A master block can have multiple detail blocks  An item can be in multiple customer orders, and have multiple shipment records  A detail block can be a master block in a second master-detail relationship  A customer can have multiple CUST_ORDER records  One CUST_ORDER record can have multiple ORDER_LINE records Complex Master-Detail Relationships

33 Master Detail Master Detail Complex Master-Detail Relationship Example

34 Formatting Text Items Specify desired format mask in text item Format Mask property If format mask makes value wider than text item Data Width property, data appears as ***** If format mask makes value wider than Visible Width property, data appears clipped

35 Formatting Character Text Items Precede format mask with “FM” Place embedded characters in double quotes

36  PL/SQL procedure that runs in response to a user or system action  Clicking a button  Loading a form  Exiting a form  Triggers can be associated with:  An entire form (form level)  A block (block level)  A specific form item (item level) Form Triggers

37  Creating a trigger:  select the form or form item event  type the trigger code  Referencing a form item in PL/SQL code:  :block_name.item_name  Triggers are compiled before a form is run Using Form Triggers

38  Create a block-level WHEN-CREATE- RECORD trigger  Trigger PL/SQL code: SELECT sequence_name.NEXTVAL INTO :block_name.item_name FROM DUAL; Using Sequences in Forms

39  List of legal values that can be selected for use in a form field LOV display LOV command button Form Lists of Values (LOVs)

40 1. Use the LOV Wizard to:  Specify the LOV display records using a SQL query  Format the LOV display  Attach the LOV to a form text item 2. Change the LOV and record group name in the Object Navigator Creating an LOV Using the LOV Wizard

41 Opening the LOV Display Place the insertion point in the text item to which the LOV is attached Press F9

42  Create a command button on the canvas  Iconic button  Displays an icon image from an.ico file  Complete path to.ico file must be specified in button’s ICON property Creating a Command Button to Open the LOV Display

43  Create a trigger for the button that does the following: 1. Places the form insertion point in the text item to which the LOV is attached: GO_ITEM(‘IN_VID’); 2. Executes the LIST_VALUES command: LIST_VALUES; LOV Command Button Trigger

44 Creating a Text Item Editor Editor: dialog box for editing character, number, or date values in text items Larger editing area than text item Provides Search and Replace functions

45 Editor Example

46 Default Editor Every text item has a default editor To open the default editor, place the insertion point in the text item and press Ctrl + e e must be lower case

47 Custom Editors Provides same editing functions as the default editor Has a customized window size, title, and appearance

48 Creating a Custom Editor Creating a new Editor object in the Object Navigator Configure the Editor object properties Attach the custom editor to the text item

49 Alternate Form Input Items Radio buttons Check boxes Lists

50  Limits user to one of two or more related, mutually exclusive choices Radio Buttons

51  Related radio buttons are part of a radio group Radio group Individual related radio buttons Radio Groups

52 1. Create the form using the Data Block and Layout Wizards 2. Open the item Property Palette, and change the Item Type value to Radio Group 3. Draw and format the radio buttons on the canvas 4. Modify the radio button properties 5. Modify the radio group properties Creating a Radio Group

53 Name: how the button is referenced within the form Label: description that appears next to the button on the canvas Radio Button Value: associated data value in the database Important Radio Button Properties

54 Name: how the radio group is referenced within the form Initial Value: data value of the radio button within the radio group that is selected when the form first appears Important Radio Group Properties

55 Form List Styles Poplist Drop-down list that user opens when needed T-List Displays current selection, and allows user to scroll up and down through choices Combo box Like a Poplist, except the user can enter a new choice if desired Lists can only display static values!

56 Examples of Form List Styles

57 1. Create the form using the Data Block and Layout Wizards 2. Open the item Property Palette, and change the Item Type value to List Item 3. Change the List Style property to the desired list style Creating a List

58 Check Boxes Used to represent fields that can have one of two values Check box caption is interpreted as TRUE or FALSE If checked, caption is true If cleared, caption is false

59 Check Box Example

60 1. Create the form using the Data Block and Layout Wizards 2. Open the item Property Palette, and change the Item Type value to Check Box 3. Modify the item properties Creating a Check Box

61 Value when Checked: data value of the item when the box is checked Important Check Box Properties Label: description that appears next to the check box on the canvas Value when Unchecked: data value of the item when the box is checked Check Box Mapping of Other Values: check box status when form first opens, or when new blank record is added