In Oracle APEX, Multi-Value List Items allow users to select multiple values from a list of options. These types of items are particularly useful when you want to allow users to choose more than one value from a predefined set of options, and the selected values will be submitted together when the form is submitted.
Multi-Value List Items can be implemented using different
types of items, such as Multi-Select Lists or Checkbox Groups.
These items are often used in situations where a user might need to choose
multiple categories, features, or other attributes that can apply
simultaneously.
Key Features of Multi-Value List Items
- Multiple
Selections:
- Unlike
single-value list items (like a drop-down list or radio buttons),
multi-value list items allow users to select more than one value at a
time.
- Flexible
Data Input:
- These
items provide flexibility in user input, allowing the submission of
multiple values that can be stored in the database, often in a
comma-separated format or using a collection.
- Use
Cases:
- Multi-value
list items are useful in scenarios such as selecting multiple categories,
features, roles, or interests. Examples include selecting multiple
product features in an online form, or multiple departments in a
work-related application.
Types of Multi-Value List Items
- Multi-Select
List:
- A Multi-Select
List is a list where users can select more than one value by holding
down the Ctrl (or Cmd on macOS) key (in most browsers) while clicking
options. Alternatively, a user can select multiple values by dragging to
select a range of options.
- This
item is implemented as a select list but with a special property
enabled to allow multiple selections.
- Example:
A user selects multiple skills (e.g., "Java," "SQL,"
"PL/SQL") in a job application form.
- Checkbox
Group:
- A Checkbox
Group displays multiple checkboxes where each checkbox corresponds to
a specific value. Users can select multiple checkboxes to select multiple
options.
- The
selected values are typically returned as a list of values, often in the
form of a comma-separated list.
- Example:
A user selecting multiple interests, such as "Sports,"
"Music," and "Travel."
- Shuttle
Item:
- A Shuttle
Item is a user interface element that allows users to select multiple
items from a list of available options and move them into a
"selected" list (usually via buttons). This is useful when
there are two lists of options (available and selected), and users can
transfer items between them.
- Example:
A user selecting multiple teams to assign to a project from a list of
available teams.
- Multi-Value
Select List:
- Similar
to the multi-select list, but this type uses a multi-select dropdown
interface (where users can scroll through and select multiple items from
the dropdown) and allows for more compact presentation.
Properties of Multi-Value List Items
- List
of Values (LOV):
- As
with other list-based items, a multi-value list item requires a List
of Values (LOV), which defines the options available for selection.
In the case of multi-value list items, the user can choose multiple
options from this list.
- Separator:
- The
selected values in a multi-value list are typically returned as a single
string, often separated by a delimiter (commas, semicolons, etc.).
Developers can specify the separator in the separator property to
control how the selected values are stored or transmitted.
- Default
Value:
- A
default value can be specified for the multi-value list item. This can be
helpful for pre-selecting options based on previous data, user
preferences, or predefined settings.
- Required:
- Multi-value
list items can also be marked as required, meaning the user must select
at least one value before submitting the form.
- Validation:
- You
can set up validation rules for multi-value list items to ensure that the
user’s selections meet certain criteria (such as a maximum number of
selections or a minimum number of selections).
Advantages of Multi-Value List Items
- User
Flexibility:
- Multi-value
list items provide users with flexibility, allowing them to select
multiple options at once, which is important in many scenarios like
survey forms, preference settings, or categorization tasks.
- Compactness:
- A
multi-select list (or checkbox group) allows users to select multiple
options within a compact space without overwhelming the user with too
many options at once. This is more efficient than using separate fields
for each possible selection.
- Data
Submission:
- Multi-value
items allow for cleaner, more efficient data submission. Instead of
requiring multiple fields for each potential value, multi-value list
items let the user select multiple options within a single input field.
The selected values are sent as a list, which can be easily processed.
- Reduced
Form Complexity:
- With
multi-value list items, you can reduce the number of fields on the form,
which enhances user experience and simplifies the design of the page.
Disadvantages of Multi-Value List Items
- Potential
for User Error:
- Since
multiple values can be selected, there is the potential for users to make
errors by selecting too many or too few options. This may lead to validation
issues, especially if not handled correctly.
- Performance
Concerns:
- If a
multi-value list is populated with a large number of items, it could
impact performance, especially in terms of page load times and
responsiveness. This is something to consider for forms with hundreds or
thousands of possible options.
- Complicated
Validation:
- Validating
multi-value inputs can be more complex compared to single-value inputs,
especially when you need to ensure that selections meet certain
conditions (e.g., at least one option is selected, or no more than a
specific number of options are selected).
Comparison of Multi-Value List Items
|
Feature |
Multi-Select List |
Checkbox Group |
Shuttle Item |
Multi-Value Select List |
|
Selection Type |
Multiple values selected using Ctrl or Shift keys |
Multiple checkboxes can be selected |
Transfer items between available and selected lists |
Multiple values can be selected in a dropdown |
|
Data Format |
Comma-separated list of selected values |
Comma-separated list of selected values |
List of selected items |
Comma-separated list of selected values |
|
UI |
Single dropdown with multi-selection |
Multiple checkboxes displayed in a group |
Two lists (available and selected) with buttons to
transfer |
Dropdown with the ability to select multiple items |
|
Ease of Use |
Easy to use for compact forms |
Intuitive for selecting multiple options |
Useful for long lists of options |
Compact dropdown interface for multiple selections |
|
Validation |
Can be validated for a minimum/maximum number of
selections |
Can be validated for a minimum/maximum number of
selections |
Custom validation for selected items |
Can be validated for a minimum/maximum number of
selections |
|
Use Case |
Selecting multiple items from a list (e.g., tags) |
Selecting multiple categories, features, or interests |
Assigning users or items to groups or projects |
Selecting multiple attributes or filters in a compact form |
Use Cases for Multi-Value List Items
- Survey
or Feedback Forms:
- A
user selects multiple preferences or feedback options, such as choosing
interests or rating multiple features in a product survey.
- Category
or Feature Selection:
- When
creating a form where users need to select multiple categories or
features, such as choosing product features, service options, or project
roles.
- Role
Assignment:
- A
system that requires multiple role assignments to a user or task (e.g.,
selecting multiple project teams, department memberships, or
permissions).
- User
Preferences:
- Allowing
users to select their preferred options from a list of predefined
choices, such as notification preferences, topics of interest, or
language selection.
- Search
Filters:
- For
filtering search results where users can select multiple filters or
attributes (e.g., selecting multiple product categories or price ranges).
Multi-Value List Items in Oracle APEX provide a powerful,
flexible solution for allowing users to select multiple options within a form.
These items are particularly useful in scenarios where users need to select
multiple attributes, categories, or filters in a single form. Whether you're
using a multi-select list, checkbox group, shuttle item, or multi-value select
list, the ability to select multiple options at once improves the user
experience and can simplify data entry and submission. However, developers must
carefully manage validation, data handling, and performance concerns to ensure
a smooth user experience.
