The APEX_APPLICATION package is a PL/SQL package that implements the Oracle Application Express rendering engine. You can use this package to take advantage of a number of global variables. Table 4-1 describes the global variables available in the APEX_APPLICATION package.
Table 4-1 Global Variables Available in APEX_APPLICATION
| Global Variable | Description |
|---|---|
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Specifies the currently logged in user. |
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Specifies the ID of the currently running application. |
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Specifies the ID of the currently running page. |
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Specifies the schema to parse for the currently running application. |
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Specifies the value of the request variable most recently passed to or set within the show or accept modules. |
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Refers to the Web browser's current language preference. |
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Refers to whether debugging is currently switched on or off. Valid values for the DEBUG flag are 'Yes' or 'No'. Turning debug on shows details about application processing. |
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Refers to the home page of an application. The Application Express engine will redirect to this location if no page is given and if no alternative page is dictated by the authentication scheme's logic. |
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Can be used to display a link to a login page for users that are not currently logged in. |
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Refers to the virtual path the web server uses to point to the images directory distributed with Oracle Application Express. |
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Refers to the owner of the Application Express schema. |
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Refers to whether or not the Application Express engine is running in print view mode. This setting can be referenced in conditions to eliminate elements not desired in a printed document from a page. |
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Refers to the application attribute 'Proxy Server'. |
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Refers to the current date on the database server. this uses the DATE DATATYPE. |
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Refers to the Oracle schema used to connect to the database through the database access descriptor (DAD). |
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Specifies the application's global notification attribute. |
Topics in this section include:
Items are typically HTML form elements such as text fields, select lists, and check boxes. When you create a new form item using a wizard, the wizard uses a standard naming format. The naming format provides a handle so you can retrieve the value of the item later on.
If you need to create your own items, you can access them after a page is submitted by referencing APEX_APPLICATION.G_F01 to APEX_APPLICATION.G_F50 arrays. You can create your own HTML form fields by providing the input parameters using the format F01, F02, F03 and so on. You can create up to 50 input parameters ranging from F01 to F50, for example:
<INPUT TYPE="text" NAME="F01" SIZE="32" MAXLENGTH="32" VALUE="some value"> <TEXTAREA NAME="F02" ROWS=4 COLS=90 WRAP="VIRTUAL">this is the example of a text area.</TEXTAREA> <SELECT NAME="F03" SIZE="1"> <OPTION VALUE="abc">abc <OPTION VALUE="123">123 </SELECT>
Because the F01 to F50 input items are declared as PL/SQL arrays, you can have multiple items named the same value. For example:
<INPUT TYPE="text" NAME="F01" SIZE="32" MAXLENGTH="32" VALUE="array element 1"> <INPUT TYPE="text" NAME="F01" SIZE="32" MAXLENGTH="32" VALUE="array element 2"> <INPUT TYPE="text" NAME="F01" SIZE="32" MAXLENGTH="32" VALUE="array element 3">
Note that following PL/SQL code produces the same HTML as show in the previous example.
FOR i IN 1..3 LOOP APEX_ITEM.TEXT(P_IDX => 1, p_value =>'array element '||i , p_size =>32, p_maxlength =>32); END LOOP;
You can reference the values posted by an HTML form using the PL/SQL variable APEX_APPLICATION.G_F01 to APEX_APPLICATION.G_F50. Because this element is an array, you can reference values directly, for example:
FOR i IN 1..APEX_APPLICATION.G_F01.COUNT LOOP
htp.p('element '||I||' has a value of '||APEX_APPLICATION.G_F01(i));
END LOOP;
Note that check boxes displayed using APEX_ITEM.CHECKBOX will only contain values in the APEX_APPLICATION arrays for those rows which are checked. Unlike other items (TEXT, TEXTAREA, and DATE_POPUP) which can contain an entry in the corresponding APEX_APPLICATION array for every row submitted, a check box will only have an entry in the APEX_APPLICATION array if it is selected.
You can also use Oracle Application Express public utility functions to convert an array into a single value. The resulting string value is a colon-separated list of the array element values. For example:
htp.p(APEX_UTIL.TABLE_TO_STRING(APEX_APPLICATION.G_F01));
This function enables you to reference G_F01 to G_F50 values in an application process that performs actions on data. The following sample process demonstrates how values are inserted into a table:
INSERT INTO my_table (my_column) VALUES APEX_UTIL.TABLE_TO_STRING(APEX_APPLICATION.G_F01)
This function outputs page and item level help text as formatted HTML and can be used to customize how help information is displayed in your application.
APEX_APPLICATION.HELP (
p_request IN VARCHAR2 DEFAULT NULL,
p_flow_id IN VARCHAR2 DEFAULT NULL,
p_flow_step_id IN VARCHAR2 DEFAULT NULL,
p_show_item_help IN VARCHAR2 DEFAULT 'YES',
p_show_regions IN VARCHAR2 DEFAULT 'YES',
p_before_page_html IN VARCHAR2 DEFAULT '<p>',
p_after_page_html IN VARCHAR2 DEFAULT NULL,
p_before_region_html IN VARCHAR2 DEFAULT NULL,
p_after_region_html IN VARCHAR2 DEFAULT '</td></tr></table></p>',
p_before_prompt_html IN VARCHAR2 DEFAULT '<p><b>',
p_after_prompt_html IN VARCHAR2 DEFAULT '</b></p>: ',
p_before_item_html IN VARCHAR2 DEFAULT NULL,
p_after_item_html IN VARCHAR2 DEFAULT NULL);
Table 4-2 describes the parameters available in the HELP procedure.
| Parameter | Description |
|---|---|
|
p_request |
Not used. |
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p_flow_id |
The application ID that contains the page or item level help you want to output. |
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p_flow_step_id |
The page ID that contains the page or item level help you want to display. |
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p_show_item_help |
Flag to determine if item level help is output. If this parameter is supplied, the value must be either 'YES' or 'NO', if not the default value will be 'YES'. |
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p_show_regions |
Flag to determine if region headers are output (for regions containing page items). If this parameter is supplied, the value must be either 'YES' or 'NO', if not the default value will be 'YES'. |
|
p_before_page_html |
Use this parameter to include HTML between the page level help text and item level help text. |
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p_after_page_html |
Use this parameter to include HTML at the bottom of the output, after all other help. |
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p_before_region_html |
Use this parameter to include HTML before every region section. Note this parameter is ignored if |
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p_after_region_html |
Use this parameter to include HTML after every region section. Note this parameter is ignored if |
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p_before_prompt_html |
Use this parameter to include HTML before every item label for item level help. Note this parameter is ignored if |
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p_after_prompt_html |
Use this parameter to include HTML after every item label for item level help. Note this parameter is ignored if |
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p_before_item_html |
Use this parameter to include HTML before every item help text for item level help. Note this parameter is ignored if |
|
p_after_item_html |
Use this parameter to include HTML after every item help text for item level help. Note this parameter is ignored if |
The following example shows how to use the APEX_APPLICATION.HELP procedure to customize how help information is displayed.
In this example, the p_flow_step_id parameter is set to :REQUEST, which means that a page ID specified in the REQUEST section of the URL will be used to control which page's help information to display (see note after example for full details on how this can be achieved).
Also, the help display has been customized so that the region sub-header now has a different color (through the p_before_region_html parameter) and also the ':' has been removed that appeared by default after every item prompt (through the p_after_prompt_html parameter).
APEX_APPLICATION.HELP(
p_flow_id => :APP_ID,
p_flow_step_id => :REQUEST,
p_before_region_html => '<p><br/><table bgcolor="#A3BED8" width="100%"><tr><td><b>',
p_after_prompt_html => '</b></p> ');
In order to implement this type of call in your application, you can do the following:
Create a page that will be your application help page.
Create a region of type 'PL/SQL Dynamic Content' and add the APEX_APPLICATION.HELP call as PL/SQL Source.
Then you can add a 'Navigation Bar' link to this page, ensuring that the REQUEST value set in the link is &APP_PAGE_ID.