15.3 Managing Page-Level Items in Component View

15.3.2.1 Creating a Page-Level Item in Component View

To create a page-level item:

1. Navigate to the appropriate page. See "Viewing a Page in Component View."

2. If necessary, create a region. See "About Regions."

3. Under Items, click the Create icon.

   The Create Item Wizard appears.

4. For Create Item:

   1. Item Type - Select an item type. See "About Item Types."

      When creating a Popup LOV, Color Picker, or Text Field with Calculator Popup, select Popup LOV and then the specific popup list of values type.

   2. Show Unsupported - Selecting No only displays items types designed for the user interface of the current page. Selecting Yes displays any additional item types which are designed for other user interfaces.

   3. Click Next.

   Select an item type. See "About Item Types."

5. For Display Position and Name:

   1. Item Name - Enter an item name. This name provides a handle for retrieving the value of the item. Item names longer than 30 characters cannot be referenced using bind variable syntax. See "About Item Naming Conventions."

   2. Sequence - Specify the sequence for this component. The sequence determines the order of evaluation.

   3. Region - Determines the region in which the item is placed.

   4. Click Next.

6. Follow the on-screen instructions.

7. To learn more about an attribute, see field-level Help. See "Viewing Field-Level Help."

15.3.2.2 Creating a Static List of Values

One way to create a static list of values is to edit an item's List of Values definition. Note that this type of list of values is not reusable. As a best practice, create a list of values as a shared component whenever possible.

To create a static list of values:

1. Navigate to the appropriate page. See "Viewing a Page in Component View."

2. If necessary, create a region. See "About Regions."

3. Under Items, click the Create icon.

   The Create Item Wizard appears.

4. For Create Item:

   1. Item Type - Select Select List.

   2. Show Unsupported - Selecting No only displays items types designed for the user interface of the current page. Selecting Yes displays any additional item types which are designed for other user interfaces.

   3. Click Next.

   Select an item type. See "About Item Types."

5. For Display Position and Name:

   1. Item Name - Enter an item name. This name provides a handle for retrieving the value of the item. Item names longer than 30 characters cannot be referenced using bind variable syntax. See "About Item Naming Conventions."

   2. Sequence - Specify the sequence for this component. The sequence determines the order of evaluation.

   3. Region - Determines the region in which the item is placed.

   4. Click Next.

6. For Item Attributes:

   1. Label - Enter an item label. The label is the text that appears next to the item when it displays. If you do not want a label, leave the label attribute blank.

   2. Height - Enter the number of rows high for the item display. For most items this should be 1.

   3. Template - Optionally, select a field template to control the display of the item.

   4. Click Next.

7. For Settings:

   1. Value Required - If set to Yes and the page item is visible, Application Express automatically performs a NOT NULL validation when the page is submitted.

      Tip:

      By defining a message called APEX.PAGE_ITEM_IS_REQUIRED in Shared Components/Text Messages, the predefined error text can be replaced by an application specific error text. The display location of the message is defined by the application-level setting Default error display location.

   2. Page Action on Selection - Specify whether multiple values or only a single value can be selected from the list of values. Multiple values are returned as a comma-separated list.

   3. Allow Multi Selection - Specify whether multiple values or only a single value can be selected from the list of values. Multiple values are returned as a comma-separated list.

   4. Click Next.

8. For List of Values:

   1. Named LOV - Select Select Named LOV.

   2. List of Values Query - Enter a query using the following syntax:

      STATIC[2]:Display Value[;Return Value],Display Value[;Return Value]
      

      Where:

      • The first keyword may be STATIC or STATIC2.

        STATIC results in the values being sorted alphabetically by display value. STATIC2 results in the values being displayed in the order they are entered in the list.

      • A semicolon separates the display value from the return value in each entry.

      • Return Value is optional. If a Return Value is not included, the return value equals the display value.

   3. Edit the remaining attributes and click Next.

9. Edit the remaining attributes as needed and click Create Item.

   The examples that follow demonstrate syntax for three different static LOVs.

STATIC:Cow,Dog,Cat,Lion

STATIC2:10,15,20,25,50,100,200,500,1000,10000

STATIC:Yes;Y,No;N

15.3.2.3 Creating a Cascading List of Values

By creating a cascading list of values (LOV), one item on a page determines the list of values for another item. Application Builder includes cascading LOV support for the following item types: Select List, Shuttle, Checkbox, Radio Group, Popup LOV, and List Manager. To learn more about item types, see "About Item Types".

You create a cascading LOV by creating two items. To populate the second item, you specify a Cascading LOV Parent Item when running the Create Item Wizard or by editing the item's attributes.

The following sections demonstrates how to create two related select lists where the value of the first list populates the second.

To create a cascading list of values:

1. Create the first item and name it P1_DEPTNO:

   1. Navigate to the appropriate page. See "Viewing a Page in Component View."

   2. If necessary, create a region. See "About Regions."

   3. Under Items, click the Create icon.

      The Create Item Wizard appears.

   4. For Item Type, select Select List.

   5. For Display Position and Name:

      • Item Name - Enter:

        P1_DEPTNO
        

      • Accept the remaining defaults and click Next.

   6. For Item Attributes:

      • Label - Enter Department

      • Accept the remaining defaults and click Next.

   7. For Settings, accept the defaults and click Next.

   8. For List of Values:

      • Display Null Value - Accept the default, Yes.

      • Null Display Value - Enter - Select Department -

        - Select Department -
        

      • In List of values definition, enter:

        SELECT dname as d,
               deptno as r
          FROM dept
         ORDER BY dname
        

      • Click Next.

   9. Accept the remaining defaults.

   10. Click Create Item.

2. Create the second item named P1_EMPNO:

   1. Navigate to the appropriate page. See "Viewing a Page in Component View."

   2. If necessary, create a region. See "About Regions."

   3. Under Items, click the Create icon.

      The Create Item Wizard appears.

   4. For Item Type, select Select List.

   5. For Display Position and Name:

      • Item Name - Enter:

        P1_EMPNO
        

      • Accept the remaining defaults and click Next.

   6. For Item Attributes:

      • Label - Enter Employee.

      • Accept the remaining defaults and click Next.

   7. For Settings, accept the defaults and click Next.

   8. For List of Values:

      • Display Null Value - Accept the default, Yes.

      • Null Display Value - Enter - Select Department -

        - Select Employee -
        

      • From Cascading LOV Parent Item(s) - Select P1_DEPTNO.

      • In List of values definition, enter:

        SELECT ename as d,
               empno as r
          FROM emp
         WHERE deptno = :P1_DEPTNO
         ORDER BY ename
        

      • Click Next.

   9. Accept the remaining defaults.

   10. Click Create Item.

3. Click Run to view a rendered version of the page.

   Two select lists appear. Making a selection in the Department select list, determines which individuals display in the Employees select list.

   
   Description of the illustration ''cascading_lov.png''
   
   

15.3.2.4 Creating Multiple Items Using a Tabular Form

To create multiple items simultaneously:

1. Navigate to the appropriate page. See "Viewing a Page in Component View."

2. If necessary, create a region. See "About Regions."

3. Access the Create Item Wizard. Under Items, click the Create icon.

   The Create Item Wizard appears.

4. Click the Create multiple items using tabular form link at the bottom of the page.

5. On the Create Multiple Items page, specify the following:

   1. Create Item(s) in Region - Select the region to contain the items.

   2. Item Template - Select an item template.

   3. For each item, enter the Sequence, Name, Label, Type and specify whether the item should be cached.

6. Click Create Multiple Items.

15.3.3.1 Editing Page Item Attributes in Component View

Once you create a page item, you can edit it on the Edit Page Item page.

To edit page item attributes:

1. Navigate to the appropriate page. See "Viewing a Page in Component View."

2. Under Items, select the item name.

   The Edit Page Item page appears.

3. To learn more about an attribute, see field-level Help. See "Viewing Field-Level Help."

4. Click Apply Changes.

15.3.3.2 Defining Default Values

You define default values for an item using the attributes under Default on the Edit Page Item page. The default value is used when the item's value is not derived from session state and when the source value is NULL.

To define a default value for an item:

1. Create the item. See "Creating Page-Level Items in Component View."

2. View the item attributes. Under Items, select the item name.

   The Edit Page Item page appears.

3. Scroll down to Default.

4. From Default Value Type, select one of the following:

   • Static Text with Session State Substitutions

   • PL/SQL Function Body

   • PL/SQL Expression

5. In Default Value, enter a value or code based on your selection.

6. Click Apply Changes.

15.3.3.3 Configuring Page Item Security

You can configure security for an item in Security region on the Edit Page Item page.

To configure page item security:

1. Create the item. See "Creating Page-Level Items in Component View."

2. View the item attributes. Under Items, select the item name.

   The Edit Page Item page appears.

3. Scroll down to Security.

4. Configure the attributes described in Table 15-3.

   Table 15-3 Edit Page Item, Security

   Attribute	Description
   Authorization Scheme	Select an authorization scheme which must evaluate to TRUE in order for this component to be rendered or otherwise processed. See Also: "Providing Security Through Authorization"
   Session State Protection	Select a Session State Protection level. Options include: Unrestricted - The item may be set by passing the item in a URL or in a form. No checksum is required in the URL. Restricted: May not be set from browser - The item may not be altered using the URL or POSTDATA. Select this option to restrict the way that the item value can be set to internal processes, computations, and so on. This attribute only applies to items that cannot be used as data entry items and is always observed, even if Session State Protection is disabled. Use this attribute for application items or for page items having the following Display As types: Display Only (Save State=No), Text Field (Disabled, does not save state), and Stop and Start Grid Layout (Displays label only). If Session State Protection is enabled, these additional attributes may be applied to items: Checksum Required: Application Level - The item may be set by passing the item in a URL if a checksum is also provided that is specific to the workspace and application. Checksum Required: User Level - The item may be set by passing the item in a URL if a checksum is also provided that is specific to the workspace, application, and user. Checksum Required: Session Level - The item may be set by passing the item in a URL if a checksum is also provided that is specific to the current session. See Also: "Understanding Session State Protection"
   Store value encrypted in session state	Session state that is sensitive can be encrypted when stored in Application Express session state management tables. To maintain session state encrypted for this item, set the value to Yes. Values up to 4000 bytes in length can be encrypted. Attempts to encrypt values longer than 4000 bytes produce an error message.
   Escape Special Characters	This attribute only displays with some item types. Select Yes to prevent Cross-Site Scripting (XSS) attacks. Select No if you want that HTML tags which are stored in the page item or in the entries of a list of value are actually rendered. See Also: "Understanding Cross-Site Scripting Protection"
   Restricted Characters	Use this attribute to restrict the characters that can be saved in session state. Oracle Application Express displays an error message if a user tries to save data which does not conform to the selected character restriction. Available options include: All Characters Allowed No restriction applies. Whitelist for a-Z, 0-9 and space Only allow characters a-z, A-Z, 0-9, and space. Blacklist HTML command characters (<>"). Do not allow reserved HTML characters Blacklist &<>"/;,*|=% and --: Do not allow &, <, >, ", /, ;, ",", *, |, =, % and "--" (PL/SQL comment). Blacklist &<>"/;,*|=% or -- and new line Do not allow &, <, >, ", /, ;, ",", *, |, =, %, "--", and new line characters See Also: "Understanding Cross-Site Scripting Protection"

   
   

15.3.3.4 Creating a Quick Pick Selection

If the item type supports quick pick selection, use the Quick Picks attributes to define up to ten selections that display under a give item. Clicking on a quick pick sets the value of item. The following example shows quick picks for 5%, 10%, 15%, and 20%.

To create a quick pick:

1. Create the item. See "Creating Page-Level Items in Component View."

2. View the item attributes. Under Items, select the item name.

   The Edit Page Item page appears.

3. Scroll down to Quick Picks.

4. From Show Quick Picks, select Yes.

5. Define the Label and Value for each quick pick:

   1. Under Label, enter the label to display for each selection.

   2. Under Value, enter the corresponding value.

6. In Link Attributes, enter additional attributes for the quick picks.

7. Click Apply Changes.

15.3.3.5 Displaying Conditional Page Items

To display a conditional item:

1. Create the item. See "Creating Page-Level Items in Component View."

2. View the item attributes. Under Items, select the item name.

   The Edit Page Item page appears.

3. Scroll down to Conditions.

4. Make a selection from the Condition Type list.

5. Enter expressions in the fields provided.

6. Click Apply Changes.

15.3.3.6 Displaying Read Only Page Items

To display a read-only item:

1. Create the item. See "Creating Page-Level Items in Component View."

2. View the item attributes. Under Items, select the item name.

   The Edit Page Item page appears.

3. Scroll down to Read Only. Under Read Only:

   1. Make a selection from Read Only Condition Type.

      Depending on the item type, a read-only item may be rendered as plain text or as nonenterable field. Not selecting a condition causes the item to render normally.

      Tip:

      Setting Condition Type to Never always renders the item as an enterable field. This setting overwrites any read-only condition setting defined at the region or page-level.

   2. Enter expressions in the fields provided.

   3. In Read Only Element Table Cell(s) Attributes, enter attributes to be included in the HTML table cell tag, <td>, that contains the item when displayed in read only mode. For example:

      bgcolor="#FF0000"
      

      Tip:

      Read Only Element Table Cell(s) Attributes only be displays if the application uses HTML tables to layout regions and page items.

4. Click Apply Changes.

15.3.3.7 Editing Multiple Items Simultaneously

Item attributes control how items display on a page. You can use the Page Items page to edit the sequence, field label, template, region, and overall position for all items on a page. The sections that follow describe how to edit items using these pages.

• Editing Multiple Items

• Reassigning Region Items

• Deleting Multiple Items

• Viewing Item Utilities

• Viewing Page Item History