Specifies the type of item. An item can be one of the following types:
ActiveX Control (32-bit Windows platforms)
Bean Area
Chart Item
Check Box
Display Item
Hierarchical Tree
Image
List Item
OLE Container
Push Button
Radio Group
Sound
Text Item
User Area
VBX Control (Microsoft Windows 3.1 only)
Subclass Information property
Specifies the following information about the source object and source module for referenced objects.
Module: The name of the source module.
Storage: The source module type (Form or Menu) and location (File System or Database)
Name: The name of the source object in the source module. (The name of a reference object can be different than the name of its source object.)
Enabled (Item) property
Determines whether end users can use the mouse to manipulate an item.
On most window managers, Enabled set to No grays out the item.
Justification property
Specifies the text justification within the item.
Left: Left justified, regardless of Reading Order property.
Center: Centered, regardless of Reading Order property.
Right: Right justified, regardless of Reading Order property.
Start: Item text is aligned with the starting edge of the item-bounding box. The starting edge depends on the value of the item's Reading Order property. Start is evaluated as Right alignment when the reading order is Right To Left, and as Left alignment when the reading order is left to Right.
End: Item text is aligned with the ending edge of the item-bounding box. The ending edge depends on the value of the item's Reading Order property. End is evaluated as Left alignment when the reading order is Right To Left, and as Right alignment when the reading order is left to Right.
Multi-Line property
Determines whether the text item is a single-line or multi-line editing region.
Setting the Multi-line property Yes allows a text item to store multiple lines of text, but it does not automatically make the item large enough to display multiple lines. It is up to you to set the Width, Height, Font Size, and Maximum Length properties to ensure that the desired number of lines and characters are displayed.
Single-line: Pressing the carriage return key while the input focus is in single-line text item initiates a [Next Item] function.
Multi-line: Pressing the carriage return key while the input focus is in a multi-line text item starts a new line in the item.
Wrap Style property
Specifies how text is displayed when a line of text exceeds the width of a text item or editor window.
NONE: No wrapping: text exceeding the right border is not shown.
CHARACTER: Text breaks following the last visible character, and wraps to the next line.
WORD: Text breaks following last visible complete word, and wraps to the next line.
Case Restriction property
Specifies the case for text entered in the text item or menu substitution parameter.
MIXED: Text appears as typed.
UPPER: Lower case text converted to upper case as it is typed.
LOWER: Upper case text converted to lower case as it is typed.
Conceal Data property
Hides characters that the operator types into the text item. This setting is typically used for password protection.
Yes Disables the echoing back of data entered by the operator.
No Enables echoing of data entered by the operator.
Keep Cursor Position property
Specifies that the cursor position be the same upon re-entering the text item as when last exited.
Automatic Skip (Item) property
Moves the cursor to the next navigable item when adding or changing data in the last character of the current item. The last character is defined by the Maximum Length property.
Popup Menu property
Specifies the popup menu to display for the canvas or item.
Keyboard Navigable property
Determines whether the end user or the application can place the input focus in the item during default navigation. When set to Yes for an item, the item is navigable. When set to No, Form Builder skips over the item and enters the next navigable item in the default navigation sequence.
At runtime, when the Enabled property is set to PROPERTY_FALSE, the Keyboard_Navigable property is also set to PROPERTY_FALSE. However, if the Enabled property is subsequently set back to PROPERTY_TRUE, the keyboard Navigable property is NOT set to PROPERTY_TRUE, and must be changed explicitly.
When Keyboard Navigable is specified at multiple levels (item instance, item, and block), the values are ANDed together. This means that setting Keyboard Navigable to Yes (or NAVIGABLE to PROPERTY_TRUE for runtime) has no effect at the item instance level unless it is set consistently at the item level. For example, your user cannot navigate to an item instance if Keyboard Navigable is true at the instance level, but not at the item level.
You can use the GO_ITEM built-in procedure to navigate to an item that has Keyboard Navigable property set to (PROPERTY_FALSE) for runtime.
Previous Navigation Item property
Specifies the name of the item that is defined as the"previous navigation item" with respect to the current item. By default, this is the item with the next lower sequence in the form, as indicated by the order of items in the Object Navigator.
Next Navigation Item property
Specifies the name of the item that is defined as the "next navigation item" with respect to this current item. By default, the next navigation item is the item with the next higher sequence as indicated by the order of items in the Object Navigator.
Copy Value from Item property
Specifies the source of the value that Form Builder uses to populate the item. When you define a master-detail relation, Form Builder sets this property automatically on the foreign key item(s) in the detail block. In such cases, the Copy Value from Item property names the primary key item in the master block whose value gets copied to the foreign key item in the detail block whenever a detail record is created or queried.
Specify this property in the form <block_name>.<block_item_name>.
Setting the Copy Value from Item property does not affect record status at runtime, because the copying occurs during default record processing.
To prevent operators from de-enforcing the foreign key relationship, set the Enabled property to No for the foreign key items.
To get the Copy Value from Item property programmatically with GET_ITEM_PROPERTY, use the constant ENFORCE_KEY.
Synchronize with Item property
Specifies the name of the item from which the current item should derive its value. Setting this property synchronizes the values of the two items, so that they effectively mirror each other. When the end user or the application changes the value of either item, the value of the other item changes also.
In earlier releases, this property was called the Mirror Item property.
You can set Synchronize with Item for base table or control blocks. When Synchronize with Item is specified, the current item's Base Table Item property is ignored, and the item derives its value from the mirror item specified, rather than from a column in the database.
If you use the GET_ITEM_PROPERTY built-in to obtain a Base Table Item property, it will obtain the value from the mirror item specified.
You can use mirror item to create more than one item in a block that display the same database column value.
Calculation Mode property
Specifies the method of computing the value of a calculated item.
None (default): Indicates the item is not a calculated item.
Formula: Indicates the item's value will be calculated as the result of a user-written formula. You must enter a single PL/SQL expression for an item's formula. The expression can compute a value, and also can call a Form Builder or user-written subprogram.
Summary: Indicates the item's value will be calculated as the result of a summary operation on a single form item. You must specify the summary type, and the item to be summarized.
Primary Key (Item) property
Indicates that the item is a base table item in a data block and that it corresponds to a primary key column in the base table. Form Builder requires values in primary key items to be unique.
Query Only property
Specifies that an item can be queried but that it should not be included in any INSERT or UPDATE statement that Form Builder issues for the block at runtime.
Query Length property
Specifies the number of characters an end user is allowed to enter in the text item when the form is Enter Query mode.
You can make the query length greater than the Maximum Length when you want to allow the end user to enter complex query conditions. For example, a query length of 5 allows an end user to enter the query condition !=500 in a text item with a Maximum Length of 3.
Case Insensitive Query property
Determines whether the operator can perform case-insensitive queries on the text item.
Case-insensitive queries are optimized to take advantage of an index. For example, assume you perform the following steps:
Create an index on the EMP table.
Set the Case Insensitive Query property on ENAME to Yes.
In Enter Query mode, enter the name 'BLAKE' into: ENAME.
Execute the query.
Form Builder constructs the following statement:
SELECT * FROM EMP WHERE UPPER (ENAME) = 'BLAKE' AND (ENAME LIKE 'Bl%' OR ENAME LIKE 'bL%' OR ENAME LIKE 'BL%' OR ENAME LIKE 'bl%');
The last part of the WHERE clause is performed first, making use of the index. Once the database finds an entry that begins with bl, it checks the UPPER (ENAME) = 'BLAKE' part of the statement, and makes the exact match.
Update Only if NULL property
Indicates that operators can modify the value of the item only when the current value of the item is NULL.
Lock Record property
Specifies that Form Builder should attempt to lock the row in the database that corresponds to the current record in the block whenever the text item's value is modified, either by the end user or programmatically.
Set this property to Yes when the text item is a control item but you still want Form Builder to lock the row in the database that corresponds to the current record in the block.
Useful for lookup text items where locking underlying record is required.
To set the Lock Record property with SET_ITEM_PROPERTY, use the constant LOCK_RECORD_ON_CHANGE.
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List of Values property
Specifies the list of values (LOV) to attach to the text item. When an LOV is attached to a text item, end users can navigate to the item and press [List of Values] to invoke the LOV.
Validate from List property
Specifies whether Form Builder should validate the value of the text item against the values in the attached LOV.
When Validate from List is Yes, Form Builder compares the current value of the text item to the values in the first column displayed in the LOV whenever the validation event occurs:
If the value in the text item matches one of the values in the first column of the LOV, validation succeeds, the LOV is not displayed, and processing continues normally.
If the value in the text item does not match one of the values in the first column of the LOV, Form Builder displays the LOV and uses the text item value as the search criteria to automatically reduce the list.
Note, however, that a When-Validate-Item trigger on the item still fires, and any validation checks you perform in the trigger still occur.
Editor property
Specifies that one of the following editors should be used as the default editor for this text item:
A user-named editor that you defined in the form or
A system editor outside of Form Builder that you specified by setting the SYSTEM_EDITOR environment variable
Visible property
Indicates whether the object is currently displayed or visible. Set Visible to Yes or No to show or hide a canvas or window.
You cannot hide the canvas that contains the current item.
You can hide a window that contains the current item.
When you use GET_WINDOW_PROPERTY to determine window visibility, Form Builder uses the following rules:
A window is considered visible if it is displayed, even if it is entirely hidden behind another window.
A window that has been iconified (minimized) is reported as visible to the operator because even though it has a minimal representation, it is still mapped to the screen.
When you use GET_VIEW_PROPERTY to determine canvas visibility, Form Builder uses the following rules:
A view is reported as visible when it is a) in front of all other views in the window or b) only partially obscured by another view.
A view is reported as not visible when it is a) a stacked view that is behind the content view in the window or b) completely obscured by a single stacked view.
The display state of the window does not affect the setting of the canvas VISIBLE property. That is, a canvas may be reported visible even if the window in which it is displayed is not currently mapped to the screen.
Rendered property
Use the Rendered property to conserve system resources. A rendered item does not require system resources until it receives focus. When a rendered item no longer has focus, the resources required to display it are released.
Hint (Item) property
Specifies item-specific help text that can be displayed on the message line of the root window at runtime. Hint text is available when the input focus is in the item.
Display Hint Automatically property
Determines when the help text specified by the item property, Hint, is displayed:
? Set Display Hint Automatically to Yes to have Form Builder display the hint text whenever the input focus enters the item.
? Set Display Hint Automatically to No to have Form Builder display the hint text only when the input focus is in the item and the end user presses [Help] or selects the Help command on the default menu.
Tooltip property
Specifies the help text that should appear in a small box beneath the item when the mouse enters the item.
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