checkbox 69 checkbox ==The checkbox widget== In the [[fields.ini file]] you can specify a field to be edited using a checkbox widget by setting [[widget:type]] to [[checkbox]]. A checkbox widget can function in 2 different ways depending on the parameters that you assign to the field. [[toc]] ===Example 1: A TinyInt (boolean) field=== Suppose our table has a tinyint field named "Active" which specifies whether the record is currently in use. This field will store a value of either 0 or 1. So we configure this field in our [[fields.ini]] file to use a checkbox widget as follows: <code> [Active] widget:type=checkbox </code> Results: [[Image:http://media.weblite.ca/files/photos/Picture%2024.png?max_width=640]] ===Example 2: A repeating field (multiple checkboxes for one field=== Checkboxes can store multiple values in a single field by setting the [[vocabulary]] directive and applying it to a varchar or text field. In this case there will be one value saved per line. In this example, suppose we have a varchar field named '''categories''' which uses the '''categories''' [[valuelist]] to specify the different categories that can be checked at any given time. Our [[valuelists.ini file]] might look like: <code> [categories] __sql__ = "select id,name from categories" </code> And our [[fields.ini file]] looks like: <code> [categories] widget:type=checkbox vocabulary=categories </code> * Note that you don't need to name the field the same as the valuelist. It just worked out this way. Now if we save a record with categories 1, 3, and 5 checked, then the categories column of our row in the database will store something like: <code> 1 3 5 </code> i.e. one category id per line. Note that using this method, your database will not be normalized because you are storing multiple values in a single field. However in many applications this is sufficient. Results: [[Image:http://media.weblite.ca/files/photos/Picture%2025.png?max_width=640]] ===Example 3: Using a "Categories" relationship=== """(Note: This example requires Xataface version 1.2 or higher)""" Example 2 above shows how we can easily add and remove a record from multiple categories using checkboxes. However it required multiple pieces of information to be stored in a single database field which may or may not be advantageous for your database design. If you're looking for a more normalized database schema you would probably design your database as follows for this case: # Books table - Stores all of the books. # Categories table - Stores all of the categories # Book_Categories table - Stores mapping of books to categories. With out table structure we will first want to define a relationship from Books to Categories to reflect the connection between books and categories. The [[relationships.ini file]] for this might look like: <code> [categories] Books.Book_ID="$Book_ID" Book_Categories.Category_ID=Categories.Category_ID </code> And our [[fields.ini file]] for the Books table might look like: <code> [categories] widget:type=checkbox transient=1 relationship=categories </code> * Note that there is no need for our field to be named the same as our relationship. It just turned out this way. Also note that we used the transient=1 flag here because the Books table no longer has a categories field in the database. This field is defined purely for the benefit of the edit form so that we will get a checkbox group to select the book's categories. Results: [[Image:http://media.weblite.ca/files/photos/Picture%2025.png?max_width=640]] ==Related Parameters== # [[vocabulary]] - Assigns a valuelist to be used as the options for this checkbox group. # [[repeat]] - A boolean value indicating whether this field should be treated as a 'repeating field'. A repeating field is one with multiple checkboxes. By default the checkbox widget operates as a single checkbox that controls a boolean value. # [[relationship]] - (Only applicable to [[transient]] fields). If the [[relationship]] directive is set then this field can be used to add/remove records from a relationship. en 0