Types of Triggers in Forms

Block-processing triggers: - Block processing triggers fire in response to events related to record management in a block. E.g. When-Create-Record, When-Clear-Block, When-Database-Record, When-Remove-Record

Interface event triggers: - Interface event triggers fire in response to events that occur in the form interface. Some of these trigger, such as When-Button-Pressed, fire only in response to operator input or manipulation. Others, like When-Window-Activated, can fire in response to both operator input and programmatic control. E.g. When-Button-Pressed, When-Checkbox-Changed, Key- [all], When-Radio-Changed, When-Timer-Expired, When-Window-Activated, When-Window-Resized

Master-detail triggers: - Form Builder generates master-detail triggers automatically when you define a master-detail relation between blocks. The default master-detail triggers enforce coordination between records in a detail block and the master record in a master block. Unless you are developing your own custom block-coordination scheme, you do not need to define these triggers yourself. Instead, simply create a relation object, and let Form Builder generate the triggers required to manage coordination between the master and detail blocks in the relation. E.g. On-Check-Delete-Master, On-Clear-Details, On-Populate-Details

Message-handling triggers: - Form Builder automatically issues appropriate error and informational messages in response to runtime events. Message handling triggers fire in response to these default messaging events. E.g. On-Error, On-Message

Navigational triggers: - Navigational triggers fire in response to navigational events. For instance, when the operator clicks on a text item in another block, navigational events occur as Form Builder moves the input focus from the current item to the target item. Navigational events occur at different levels of the Form Builder object hierarchy (Form, Block, Record, Item). Navigational triggers can be further sub-divided into two categories: Pre- and Post- triggers, and When-New-Instance triggers. Pre- and Post- triggers fire as Form Builder navigates internally through different levels of the object hierarchy. As you might expect, these triggers fire in response to navigation initiated by an operator, such as pressing the [Next Item] key. However, be aware that these triggers also fire in response to internal navigation that Form Builder performs during default processing. To avoid unexpected results, you must consider such internal navigation when you use these triggers. E.g. Pre-Form, Pre-Block, Pre-Text-Item, Post-Text-Item, Post-Record, Post-Block, Post-Form
When-New-Instance triggers fire at the end of a navigational sequence that places the input focus in a different item. Specifically, these triggers fire just after Form Builder moves the input focus to a different item, when the form returns to a quiet state to wait for operator input. Unlike the Pre- and Post- navigational triggers, the When-New-Instance triggers do not fire in response to internal navigational events that occur during default form processing. E.g. When-New-Form-Instance, When-New-Block-Instance, When-New-Record-Instance, When-New-Item-Instance

Query-time triggers: - Query-time triggers fire just before and just after the operator or the application executes a query in a block. E.g. Pre-Query, Post-Query

Transactional triggers: - Transactional triggers fire in response to a wide variety of events that occur as a form interacts with the data source. E.g. On-Delete, On-Insert, On-Lock, On-Logon, On-Update, Post-Database-Commit, Post-Delete, Post-Forms-Commit, Post-Insert, Post-Update, Pre-Commit, Pre-Delete, Pre-Insert, Pre-Update

Validation triggers: - Validation triggers fire when Form Builder validates data in an item or record. Form Builder performs validation checks during navigation that occurs in response to operator input, programmatic control, or default processing, such as a Commit operation. E.g. When-Validate-Item, When-Validate-Record

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