install4j API

com.install4j.api.formcomponents
Interface FormEnvironment


public interface FormEnvironment

The form environment gives access to form components in a form panel as well as to other design time or runtime services related to form components.

It provides access to the ComponentTuple of a form component as well as to the IDs that the framework assigns to form components. Furthermore, the form environment contains utility methods that can be used at design time. This class is passed to the containing screen as well as to every form component.

Author:
ej-technologies GmbH
See Also:
FormPanelContainer.setFormPanel(javax.swing.JPanel, FormEnvironment), FormComponent.setFormEnvironment(FormEnvironment)

Method Summary
 void addDesignTimeChangeListener(javax.swing.event.ChangeListener changeListener)
          If your form component would like to be notified when the list of form components changes at design time, you can add a change listener here.
 ComponentTuple getComponentTuple(FormComponent formComponent)
          Get the ComponentTuple associated with a form component.
 java.lang.String getDesignTimeName(FormComponent formComponent)
          At design time, the install4j GUI allows the user to name instances of form components in a form.
 java.lang.String getDesignTimeName(LayoutGroup layoutGroup)
          At design time, the install4j GUI allows the user to name instances of layout groups in a form.
 FormComponent getFormComponentById(java.lang.String id)
          Get the form component of a certain ID.
 FormComponent[] getFormComponents()
          Returns all form components that are contained in the same form.
 java.util.List getFormComponentTree()
          Returns the top level of the tree of form components.
 java.lang.String getId(FormComponent formComponent)
          Get the ID that the framework associates with a form component.
 LayoutGroup getLayoutGroupById(java.lang.String id)
          Get the layout group of a certain ID.
 Screen getScreen()
          Get the form screen associated with this form environment.
 boolean handleConsole(Console console)
          Handle console mode for all form components in a form.
 boolean isDesignTime()
          Returns whether the form component has been instantiated at design time.
 void makeParentGroupVisible(FormComponent formComponent)
          Makes the parent group of a form component visible.
 void reinitializeFormComponents()
          All form components including those that do not have their "Reset initialization on previous" property selected are initialized again.
 void removeDesignTimeChangeListener(javax.swing.event.ChangeListener changeListener)
          Remove a change listener added with addDesignTimeChangeListener.
 void resetFormComponents()
          All form components whose "Reset initialization on previous" property is selected, will be initialized again when the screen is shown the next time.
 boolean saveFormComponents()
          All form components will be validated and their variables will be saved.
 

Method Detail

getFormComponents

FormComponent[] getFormComponents()
Returns all form components that are contained in the same form. Note that the setFormEnvironment is called twice at runtime and that only the second invocation passes a FormEnvironment that returns all form components when calling this method.

If you need to access layout groups, please see getFormComponentTree() instead.

Returns:
an array of all form components or the empty array if the form is not fully initialized
See Also:
FormComponent.setFormEnvironment(FormEnvironment)

getFormComponentTree

java.util.List getFormComponentTree()
Returns the top level of the tree of form components. The list contains objects of two different classes: FormComponent and LayoutGroup. Deeper levels can be accessed with LayoutGroup.getChildren() on the LayoutGroup objects.

Returns:
a list with the top level form components and layout groups

getId

java.lang.String getId(FormComponent formComponent)
Get the ID that the framework associates with a form component. When form components refer to other form components and wish to transfer those associations between design time and runtime, they have to store a IDs rather than the form components themselves. The translation between IDs and form components is provided by the form environment.

The ID can be transformed back to the form component with the getFormComponentById method.

Parameters:
formComponent - the form component whose ID should be returned
Returns:
the ID
See Also:
getFormComponentById(String)

getFormComponentById

FormComponent getFormComponentById(java.lang.String id)
Get the form component of a certain ID. See getId(FormComponent) method for more details.

Parameters:
id - the ID of the form component
Returns:
the form component or null if no such ID can be found.

getLayoutGroupById

LayoutGroup getLayoutGroupById(java.lang.String id)
Get the layout group of a certain ID. See LayoutGroup.getId() for more details.

Parameters:
id - the ID of the layout group
Returns:
the layout group or null if no such ID can be found.

getComponentTuple

ComponentTuple getComponentTuple(FormComponent formComponent)
Get the ComponentTuple associated with a form component.

Parameters:
formComponent - the form component whose ComponentTuple should be returned
Returns:
the ComponentTuple

handleConsole

boolean handleConsole(Console console)
                      throws UserCanceledException
Handle console mode for all form components in a form. This method has to be called at some point in the handleConsole method of the containing screen, otherwise the handleConsole method of the FormComponent will not be called.

Parameters:
console - the Console object as passed to the handleConsole method of the containing screen.
Returns:
whether the installer should continue or not. This value should be passed on in the handleConsole method of the containing screen which is the only place where this method should be called.
Throws:
UserCanceledException - if the user cancels a question or notice. This exception can be passed on to the framework.
See Also:
FormComponent.handleConsole(com.install4j.api.screens.Console), Screen.handleConsole(com.install4j.api.screens.Console)

isDesignTime

boolean isDesignTime()
Returns whether the form component has been instantiated at design time. At design time, the context passed to a form component is null.

Returns:
true or false.

addDesignTimeChangeListener

void addDesignTimeChangeListener(javax.swing.event.ChangeListener changeListener)
If your form component would like to be notified when the list of form components changes at design time, you can add a change listener here. Only a weak reference to the listener is held, so the garbage collection of your form component is not influenced.

This method has no effect at runtime.

Parameters:
changeListener - the listener

removeDesignTimeChangeListener

void removeDesignTimeChangeListener(javax.swing.event.ChangeListener changeListener)
Remove a change listener added with addDesignTimeChangeListener.

This method has no effect at runtime.

Parameters:
changeListener - the listener

getDesignTimeName

java.lang.String getDesignTimeName(FormComponent formComponent)
At design time, the install4j GUI allows the user to name instances of form components in a form. You can retrieve that name with this method.

Parameters:
formComponent - the form component whose name should be returned.
Returns:
name the design time name or null if called at runtime

getDesignTimeName

java.lang.String getDesignTimeName(LayoutGroup layoutGroup)
At design time, the install4j GUI allows the user to name instances of layout groups in a form. You can retrieve that name with this method.

Parameters:
layoutGroup - the layout group whose name should be returned.
Returns:
name the design time name or null if called at runtime

getScreen

Screen getScreen()
Get the form screen associated with this form environment.

Returns:
the screen

resetFormComponents

void resetFormComponents()
All form components whose "Reset initialization on previous" property is selected, will be initialized again when the screen is shown the next time. Usually, initialization is only reset when the user presses the "Back button" on the form screen. If you implement a loop and want to reset the initialization, you have to call this method. The following code retrieves a form screen by ID and resets its form components:

 String screenId = ...
 // must be a form screen for the cast to work
 FormPanelContainer formPanelContainer = (FormPanelContainer)context.getScreenById(id);
 formPanelContainer.getFormEnvironment().resetFormComponents()

 


reinitializeFormComponents

void reinitializeFormComponents()
All form components including those that do not have their "Reset initialization on previous" property selected are initialized again. This is useful for implementing a "Reset" button that brings the form to its original state.


saveFormComponents

boolean saveFormComponents()
All form components will be validated and their variables will be saved. This is what happens automatically when the user clicks "Next" just before the validation expression of the screen is evaluated. If you need save the form components to variables while the screen is being shown, you can use this method. For example, a button form component might require some variables of other form components to be set to the currently entered values.

Returns:
if the validation was successful. If false, only form components up to the offending form component are saved.

makeParentGroupVisible

void makeParentGroupVisible(FormComponent formComponent)
Makes the parent group of a form component visible. This is useful if a form component is located beneath a tabbed pane group and the currently displayed tab is different than the parent tab of the form component.

Parameters:
formComponent - the form component whose parent group should be made visible.

install4j API