org.sandev.ui.structs
Class ActionStruct

java.lang.Object
  org.sandev.ui.structs.ActionStruct

Direct Known Subclasses:

Action

public class ActionStruct
extends java.lang.Object

An action represents a call to an application function.

SandUI
Screen
Link
Action

The SandUIAdaptor relies on a UIScreenAdaptor for rendering and reconstruction of a display screen. The UIScreenAdaptor relies on the actionStatus field value, and the UIFormOwner isActive method, to gate which actions are applied.

Actions are divided into three broad types:

• setup actions initialize forms.
• request actions are buttons that the user can press to trigger action processing logic.
• value actions are evaluated to produce output information.

Actions co-exist with the SANDForms processing. Here's how a full processing cycle works:

1. A new Screen instance is initialized from the SandUI declaration.
2. UIFormContext instances are restored/initialized for any Link with associated actions (for example FORM Links).
3. The actions are processed:
   • if UIFormContext.action is CUSTOM then call UIFormOwner.doAction with the request action name.
   • if UIFormContext.action is a standard action (something other than CUSTOM or INIT), then call UIFormManager.processForm to handle the action.
   • if UIFormContext.action is INIT then call UIFormOwner.doAction with the setup action name (defaults to formnameInit). Either standard or custom action processing may explicitely trigger initialization by setting the action to INIT on completion.
4. Render the Screen instance, rendering each Link in the order declared. Within each Link, render active requests and active values as determined by the actionStatus and the value of UIFormOwner.isActive for the action name.

Each Action is associated with a Link, which determines its source scope. For a FORM link, the UIFormContext passed to doAction is the UIFormContext for the form. For a TEXT link, the UIFormContext passed to doAction contains only the current userID, and is otherwise undefined.

All actions produce a UIFormContext. For a value action, the displayed result is the summary information for the currInst object. To return only a single value, set the currInst to a Value message. For a request or value action, the result is the form information. If a request or value action is used in a TEXT link then the result is ignored (the action is used only for side-effects).

Additional notes:

• We generally recommend against filtering of form data (except for authentication processing) since reconciliation of displayed data and database data can cause headaches. This perceived need can frequently be addressed through improved data representation.
• UI representational state can depend on an arbitrary level of system state information ranging from a few global state flags to sophisticated calculations involving users, state, stats and other information. To avoid lock-in, avoid technology-specific mechanisms and represent the required information within the core application components.

summary fields: name actionType displayName

Field Summary

protected int	actionStatus Whether this action is active or not.
protected int	actionType What kind of action this is.
protected java.lang.String	displayName The text name for the action button.
protected java.lang.String	name The identifying name of this action.

Constructor Summary

ActionStruct()

Method Summary

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

displayName

protected java.lang.String displayName

The text name for the action button. If the UIScreenAdaptor supports localization, then this name is used as a lookup key for localized text. Otherwise this name is displayed directly.

name

protected java.lang.String name

The identifying name of this action. The name is used for the UIFormOwner isActive and formAction method calls.

actionStatus

protected int actionStatus

Whether this action is active or not. This can be switched unconditionally when declared, or switched at runtime by the UIFormOwner isActive method.

declared default value: INACTIVE

enumerated constant values:

• DISABLED("disabled, always inactive") = 1
  
• INACTIVE("inactive, unless runtime activated") = 2
  
• ACTIVE("active, unless runtime inactivated") = 3
  
• UNCONDITIONAL("unconditional, always active") = 4
  

declared invalid value: 0

actionType

protected int actionType

What kind of action this is. See the class notes for details.

declared default value: REQUEST

enumerated constant values:

• SETUP("setup") = 1
  
• REQUEST("request") = 2
  
• VALUE("value") = 3
  

declared invalid value: 0

Constructor Detail

ActionStruct

public ActionStruct()