Package com.storedobject.vaadin

Class AbstractForm<D>

java.lang.Object

com.vaadin.flow.component.Component

com.vaadin.flow.component.Composite<com.vaadin.flow.component.Component>

com.storedobject.vaadin.AbstractForm<D>

Type Parameters:

D - Type of data object in the form

All Implemented Interfaces:

com.vaadin.flow.component.AttachNotifier, com.vaadin.flow.component.DetachNotifier, com.vaadin.flow.component.HasElement, com.vaadin.flow.component.HasStyle, Serializable

Direct Known Subclasses:

Form, ObjectForm

public abstract class AbstractForm<D>
extends com.vaadin.flow.component.Composite<com.vaadin.flow.component.Component>

Class to represent a "data entry form". A "field" in the form is a HasValue. Form internally keeps Data that is a structure that keeps data for all the "fields" of the form.

A form is not used directly in most cases. Instead, a View derived from AbstractDataForm is used where a form is already embedded. All overridable methods in the form can be defined in AbstractDataForm too.

If at all required to use it directly, one should use Form instead of AbstractForm.

Author:

Syam

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected class	AbstractForm.ValueHandler	Basic value-handler implementation.

Field Summary

Fields

Modifier and Type	Field	Description
protected com.vaadin.flow.component.HasComponents	container	The field container of the form.
protected final Data<D>	data	The "data" associated with this form.
protected final Class<D>	objectClass	Class of the data object in the form.
protected D	objectData	Current instance of the data object in the form.

Constructor Summary

Constructors

Modifier	Constructor	Description
	AbstractForm(Class<D> objectClass)	Construct a form.
	AbstractForm(Class<D> objectClass, com.vaadin.flow.component.HasComponents container)	Construct a form with a specified field container.
protected	AbstractForm(Class<D> objectClass, com.vaadin.flow.component.HasComponents container, Object dummy)	For internal use only.

Method Summary

Modifier and Type	Method	Description
void	add(com.vaadin.flow.component.Component... components)	Add components to the form's field container.
void	addField(com.vaadin.flow.component.HasValue<?,?> field)	Add a field to the form.
void	addField(String fieldName, com.vaadin.flow.component.HasValue<?,?> field)	Add a field to the form.
void	addFields(com.vaadin.flow.component.HasValue<?,?>... fields)	Add multiple fields to the form.
com.vaadin.flow.shared.Registration	addIncludeFieldChecker(IncludeField includeField)	Add an "include field checker" to the existing chain.
<F> void	addValidator(com.vaadin.flow.component.HasValue<?,F> field, Function<F,Boolean> validator)	Add a validator for the field.
<F> void	addValidator(com.vaadin.flow.component.HasValue<?,F> field, Function<F,Boolean> validator, String errorMessage)	Add a validator for the field.
protected void	attachField(String fieldName, com.vaadin.flow.component.HasValue<?,?> field)	Attach a field to the form.
static void	clearError(com.vaadin.flow.component.HasValue<?,?> field)	Clear the error status associated with a field.
void	clearErrors()	Clear error status of all the fields.
void	clearFields()	Clear values of all the fields.
boolean	commit()	Save data from the fields to the internal data structure.
boolean	connect(com.vaadin.flow.component.HasValue<?,?>... fields)	Connect fields so that a change in any of it is propagated to others within that connected group.
boolean	connect(String... fieldNames)	Connect fields so that a change in any of it is propagated to others within that connected group.
boolean	connect(Collection<com.vaadin.flow.component.HasValue<?,?>> fields)	Connect fields so that a change in any of it is propagated to others within that connected group.
protected void	constructed()	This method is invoked when the "fields" are created and the form is ready to display.
protected com.vaadin.flow.component.HasComponents	createContainer()	Create the field container of this form.
protected com.vaadin.flow.component.HasValue<?,?>	createField(String fieldName)	Create the field for a particular "field name".
protected com.vaadin.flow.component.HasValue<?,?>	createField(String fieldName, String label)	Create the field for a particular "field name".
protected D	createObjectInstance()	Create an instance of the data object.
protected void	detachField(String fieldName, com.vaadin.flow.component.HasValue<?,?> field)	Detach a field from the form.
void	dumpValues()	Print values from the internal data structure to System.err (Used for debugging purposes).
protected void	generateFieldNames()	For internal use only.
com.vaadin.flow.data.binder.Binder<D>	getBinder()	Get the data binder.
final int	getColumns()	Get number of responsive columns for the form.
int	getColumnSpan(com.vaadin.flow.component.Component component)	Get the column span of a component.
final com.vaadin.flow.component.Component	getComponent()	Get the field container of the form as a component.
final com.vaadin.flow.component.HasComponents	getContainer()	Get the field container of the form.
final com.vaadin.flow.component.Component	getContent()
com.vaadin.flow.component.HasText	getErrorDisplay()	Get the current error display of the form.
final com.vaadin.flow.component.HasValue<?,?>	getField(String fieldName)	Get a field associated with a field name.
final String	getFieldLabel(com.vaadin.flow.component.HasValue<?,?> field)	Get label for the given field.
final String	getFieldLabel(String fieldName)	Get label for the given field.
final String	getFieldName(com.vaadin.flow.component.HasValue<?,?> field)	Get a field name associated with a field.
protected Stream<String>	getFieldNames()	Get the field names.
String	getLabel(String fieldName)	This method is invoked to determine the label used for displaying the field.
D	getObject()	Get the instance of the currently editing data object.
D	getObject(boolean create)	Get the instance of the currently editing data object.
View	getView()	Get the associated view of this form.
protected final com.vaadin.flow.component.Component	initContent()
boolean	isFieldEditable(com.vaadin.flow.component.HasValue<?,?> field)	This method is invoked to determine if a field needs to be made editable or not.
boolean	isFieldEditable(String fieldName)	This method is invoked to determine if a field needs to be made editable or not.
boolean	isFieldVisible(com.vaadin.flow.component.HasValue<?,?> field)	This method is invoked to determine if a field needs to be made visible or not.
boolean	isFieldVisible(String fieldName)	This method is invoked to determine if a field needs to be made visible or not.
boolean	isReadOnly()	Check whether the form is "read only" or not.
void	load()	Load data to the fields from the internal data structure.
static void	markError(com.vaadin.flow.component.HasValue<?,?> field)	Mark a field as not valid.
void	newLine()	Add a new line to the form.
void	remove(com.vaadin.flow.component.Component... components)	Remove components from the form's field container.
void	removeAll()	Remove all components from the form's field container.
void	removeField(com.vaadin.flow.component.HasValue<?,?> field)	Remove a field from the form.
void	removeField(String fieldName)	Remove a field from the form.
void	removeField(String... fieldNames)	Remove fields from the form.
void	setColumns(int columns)	Set number of responsive columns for the form.
void	setColumnSpan(com.vaadin.flow.component.Component component, int columnSpan)	Set number of columns to span for a particular component.
void	setErrorDisplay(com.vaadin.flow.component.HasText display)	Error messages of the form are typically displayed using Notification.
final void	setFieldLabel(com.vaadin.flow.component.HasValue<?,?> field, String label)	Set label for a specific field.
final void	setFieldLabel(String fieldName, String label)	Set label for a specific field.
void	setIncludeFieldChecker(IncludeField includeField)	Set "include field checker".
void	setObject(D object)	Set the current object.
void	setObject(D object, boolean load)	Set the current object.
void	setReadOnly(boolean readOnly)	Set the form read only.
void	setRequired(com.vaadin.flow.component.HasValue<?,?> field)	Set the "required" attribute of a field.
void	setRequired(com.vaadin.flow.component.HasValue<?,?> field, boolean required)	Set the "required" attribute of a field.
void	setRequired(com.vaadin.flow.component.HasValue<?,?> field, boolean required, String errorMessage)	Set the "required" attribute of a field.
void	setRequired(com.vaadin.flow.component.HasValue<?,?> field, String errorMessage)	Set the "required" attribute of a field.
void	setRequired(String fieldName)	Set the "required" attribute of a field.
void	setRequired(String fieldName, boolean required)	Set the "required" attribute of a field.
void	setRequired(String fieldName, boolean required, String errorMessage)	Set the "required" attribute of a field.
void	setRequired(String fieldName, String errorMessage)	Set the "required" attribute of a field.
void	setView(View view)	Set an associated view for this form.
final Stream<String>	streamFieldNamesCreated()	Get all fields names.
final Stream<com.vaadin.flow.component.HasValue<?,?>>	streamFieldsCreated()	Get all fields.

Methods inherited from class com.vaadin.flow.component.Composite

getChildren, getElement

Methods inherited from class com.vaadin.flow.component.Component

addListener, findAncestor, fireEvent, from, get, getEventBus, getId, getListeners, getLocale, getParent, getTranslation, getTranslation, getTranslation, getTranslation, getTranslation, getTranslation, getUI, hasListener, isAttached, isTemplateMapped, isVisible, onAttach, onDetach, onEnabledStateChanged, removeFromParent, scrollIntoView, scrollIntoView, set, setElement, setId, setVisible

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.vaadin.flow.component.AttachNotifier

addAttachListener

Methods inherited from interface com.vaadin.flow.component.DetachNotifier

addDetachListener

Methods inherited from interface com.vaadin.flow.component.HasStyle

addClassName, addClassNames, getClassName, getClassNames, getStyle, hasClassName, removeClassName, removeClassNames, setClassName, setClassName

Field Details

objectClass

protected final Class<D> objectClass

Class of the data object in the form.

objectData

protected D objectData

Current instance of the data object in the form.

container

protected com.vaadin.flow.component.HasComponents container

The field container of the form.

data

protected final Data<D> data

The "data" associated with this form.

Constructor Details

AbstractForm

public AbstractForm(Class<D> objectClass)

Construct a form.

Parameters:

objectClass - Type of the data object

AbstractForm

public AbstractForm(Class<D> objectClass,
 com.vaadin.flow.component.HasComponents container)

Construct a form with a specified field container.

Parameters:

objectClass - Type of the data object

container - Field container of the form.

AbstractForm

protected AbstractForm(Class<D> objectClass,
 com.vaadin.flow.component.HasComponents container,
 Object dummy)

For internal use only.

Parameters:

objectClass - Type of the data object

container - Field container of the form.

dummy - Dummy value, not used

Method Details

initContent

protected final com.vaadin.flow.component.Component initContent()

Overrides:

initContent in class com.vaadin.flow.component.Composite<com.vaadin.flow.component.Component>

getContent

public final com.vaadin.flow.component.Component getContent()

Overrides:

getContent in class com.vaadin.flow.component.Composite<com.vaadin.flow.component.Component>

getBinder

public com.vaadin.flow.data.binder.Binder<D> getBinder()

Get the data binder. (For internal use only).

Returns:

Data binder associated with this form.

setIncludeFieldChecker

public void setIncludeFieldChecker(IncludeField includeField)

Set "include field checker". It will determine if a field can be added or not.

Parameters:

includeField - The "include field checker"

addIncludeFieldChecker

public com.vaadin.flow.shared.Registration addIncludeFieldChecker(IncludeField includeField)

Add an "include field checker" to the existing chain. If any one of the IncludeField in the chain returns false for a specific field, the field will not be included in the form.

Parameters:

includeField - The "include field checker" to add.

Returns:

Registration.

createContainer

protected com.vaadin.flow.component.HasComponents createContainer()

Create the field container of this form. This will be invoked only if no container was already set. Default implementation creates a FormLayout.

Returns:

Field container created.

generateFieldNames

protected void generateFieldNames()

For internal use only.

getContainer

public final com.vaadin.flow.component.HasComponents getContainer()

Get the field container of the form.

Returns:

Field container.

constructed

protected void constructed()

This method is invoked when the "fields" are created and the form is ready to display.

getComponent

public final com.vaadin.flow.component.Component getComponent()

Get the field container of the form as a component.

Returns:

Field container as a component. null is returned if the field container is not a component.

getFieldNames

protected Stream<String> getFieldNames()

Get the field names. This is invoked to determine the fields to be created for constructing the form.

Returns:

Stream of fields.

createField

protected com.vaadin.flow.component.HasValue<?,?> createField(String fieldName)

Create the field for a particular "field name".

Parameters:

fieldName - Field name

Returns:

Field created.

createField

protected com.vaadin.flow.component.HasValue<?,?> createField(String fieldName,
 String label)

Create the field for a particular "field name".

Parameters:

fieldName - Field name

label - Label for the field

Returns:

Field created.

addField

public void addField(com.vaadin.flow.component.HasValue<?,?> field)

Add a field to the form. The field will not be having a "field name".

Parameters:

field - Field to be added

addFields

public void addFields(com.vaadin.flow.component.HasValue<?,?>... fields)

Add multiple fields to the form. These fields will not be having "field names".

Parameters:

fields - Fields to be added

addField

public void addField(String fieldName,
 com.vaadin.flow.component.HasValue<?,?> field)

Add a field to the form.

Parameters:

fieldName - Name associated with the field

field - Field

removeField

public void removeField(String fieldName)

Remove a field from the form.

Parameters:

fieldName - Name of the field to be removed

removeField

public void removeField(String... fieldNames)

Remove fields from the form.

Parameters:

fieldNames - Names of the field to be removed

removeField

public void removeField(com.vaadin.flow.component.HasValue<?,?> field)

Remove a field from the form.

Parameters:

field - Field to be removed.

attachField

protected void attachField(String fieldName,
 com.vaadin.flow.component.HasValue<?,?> field)

Attach a field to the form. This is invoked whenever a field is added to the form. The default implementation adds the field component (if it is a component) to the field container.

Parameters:

fieldName - Name of the field

field - Field

detachField

protected void detachField(String fieldName,
 com.vaadin.flow.component.HasValue<?,?> field)

Detach a field from the form. This is invoked whenever a field is removed to the form. The default implementation removes the field component (if it is a component) from the field container.

Parameters:

fieldName - Name of the field

field - Field

add

public void add(com.vaadin.flow.component.Component... components)

Add components to the form's field container.

Parameters:

components - Components to add

remove

public void remove(com.vaadin.flow.component.Component... components)

Remove components from the form's field container.

Parameters:

components - Components to remove

removeAll

public void removeAll()

Remove all components from the form's field container.

setColumns

public void setColumns(int columns)

Set number of responsive columns for the form. (This will work only when the container is of type FormLayout).

Parameters:

columns - Number of responsive columns required

getColumns

public final int getColumns()

Get number of responsive columns for the form. (This will work only when the container is of type FormLayout).

Returns:

Number of responsive columns of the form.

newLine

public void newLine()

Add a new line to the form. (This will work only when the container is of type FormLayout).

setColumnSpan

public void setColumnSpan(com.vaadin.flow.component.Component component,
 int columnSpan)

Set number of columns to span for a particular component. (This will work only when the container is of type FormLayout).

Parameters:

component - Component for which column span to be set

columnSpan - Number of columns to span

getColumnSpan

public int getColumnSpan(com.vaadin.flow.component.Component component)

Get the column span of a component. (This will work only when the container is of type FormLayout).

Parameters:

component - Component for which column span to be retrieved

Returns:

Column span for the component.

load

public void load()

Load data to the fields from the internal data structure.

commit

public boolean commit()

Save data from the fields to the internal data structure.

Returns:

True if data is saved successfully.

dumpValues

public void dumpValues()

Print values from the internal data structure to System.err (Used for debugging purposes).

streamFieldsCreated

public final Stream<com.vaadin.flow.component.HasValue<?,?>> streamFieldsCreated()

Get all fields.

Returns:

Stream of fields.

streamFieldNamesCreated

public final Stream<String> streamFieldNamesCreated()

Get all fields names.

Returns:

Stream of field names.

getField

public final com.vaadin.flow.component.HasValue<?,?> getField(String fieldName)

Get a field associated with a field name.

Parameters:

fieldName - Name of the field

Returns:

Field.

getFieldName

public final String getFieldName(com.vaadin.flow.component.HasValue<?,?> field)

Get a field name associated with a field.

Parameters:

field - Field

Returns:

Name of the field.

setRequired

public void setRequired(com.vaadin.flow.component.HasValue<?,?> field)

Set the "required" attribute of a field. If set to true, with empty data (checked by invoking HasValue.isEmpty()), commit() will fail.

Parameters:

field - Field

setRequired

public void setRequired(String fieldName)

Set the "required" attribute of a field. If set to true, with empty data (checked by invoking HasValue.isEmpty()), commit() will fail.

Parameters:

fieldName - Field name

setRequired

public void setRequired(com.vaadin.flow.component.HasValue<?,?> field,
 String errorMessage)

Set the "required" attribute of a field. If set to true, with empty data (checked by invoking HasValue.isEmpty()), commit() will fail.

Parameters:

field - Field

errorMessage - Error message to show when the field is empty

setRequired

public void setRequired(String fieldName,
 String errorMessage)

Set the "required" attribute of a field. If set to true, with empty data (checked by invoking HasValue.isEmpty()), commit() will fail.

Parameters:

fieldName - Field name

errorMessage - Error message to show when the field is empty

setRequired

public void setRequired(com.vaadin.flow.component.HasValue<?,?> field,
 boolean required)

Set the "required" attribute of a field. If set to true, with empty data (checked by invoking HasValue.isEmpty()), commit() will fail.

Parameters:

field - Field

required - True or false

setRequired

public void setRequired(String fieldName,
 boolean required)

Set the "required" attribute of a field. If set to true, with empty data (checked by invoking HasValue.isEmpty()), commit() will fail.

Parameters:

fieldName - Field name

required - True or false

setRequired

public void setRequired(com.vaadin.flow.component.HasValue<?,?> field,
 boolean required,
 String errorMessage)

Set the "required" attribute of a field. If set to true, with empty data (checked by invoking HasValue.isEmpty()), commit() will fail.

Parameters:

field - Field

required - True or false

errorMessage - Error message to show when the field is empty

setRequired

public void setRequired(String fieldName,
 boolean required,
 String errorMessage)

Set the "required" attribute of a field. If set to true, with empty data (checked by invoking HasValue.isEmpty()), commit() will fail.

Parameters:

fieldName - Field name

required - True or false

errorMessage - Error message to show when the field is empty

addValidator

public <F> void addValidator(com.vaadin.flow.component.HasValue<?,F> field,
 Function<F,Boolean> validator)

Add a validator for the field. Validator should return true if the field is valid.

Type Parameters:

F - Type of the field value.

Parameters:

field - Field

validator - Validator

addValidator

public <F> void addValidator(com.vaadin.flow.component.HasValue<?,F> field,
 Function<F,Boolean> validator,
 String errorMessage)

Add a validator for the field. Validator should return true if the field is valid.

Type Parameters:

F - Type of the field value.

Parameters:

field - Field

validator - Validator

errorMessage - Error message to be displayed if the field is not valid

markError

public static void markError(com.vaadin.flow.component.HasValue<?,?> field)

Mark a field as not valid.

Parameters:

field - Field

clearError

public static void clearError(com.vaadin.flow.component.HasValue<?,?> field)

Clear the error status associated with a field.

Parameters:

field - Field

clearFields

public void clearFields()

Clear values of all the fields.

clearErrors

public void clearErrors()

Clear error status of all the fields.

setErrorDisplay

public void setErrorDisplay(com.vaadin.flow.component.HasText display)

Error messages of the form are typically displayed using Notification. However, one can set any HasText for that.

Parameters:

display - Error messages will be displayed on this

getErrorDisplay

public com.vaadin.flow.component.HasText getErrorDisplay()

Get the current error display of the form. (See setErrorDisplay(HasText)).

Returns:

Current error display.

setReadOnly

public void setReadOnly(boolean readOnly)

Set the form read only.

Parameters:

readOnly - True or false

isReadOnly

public boolean isReadOnly()

Check whether the form is "read only" or not.

Returns:

True or false.

isFieldVisible

public boolean isFieldVisible(String fieldName)

This method is invoked to determine if a field needs to be made visible or not.

Parameters:

fieldName - Name of the field

Returns:

True or false.

isFieldVisible

public boolean isFieldVisible(com.vaadin.flow.component.HasValue<?,?> field)

This method is invoked to determine if a field needs to be made visible or not.

Parameters:

field - Field

Returns:

True or false.

isFieldEditable

public boolean isFieldEditable(String fieldName)

This method is invoked to determine if a field needs to be made editable or not.

Parameters:

fieldName - Name of the field

Returns:

True or false.

isFieldEditable

public boolean isFieldEditable(com.vaadin.flow.component.HasValue<?,?> field)

This method is invoked to determine if a field needs to be made editable or not.

Parameters:

field - Field

Returns:

True or false.

getLabel

public String getLabel(String fieldName)

This method is invoked to determine the label used for displaying the field. The default implementation determine it by invoking ApplicationEnvironment.createLabel(String).

Parameters:

fieldName - Name of the field

Returns:

Label

setFieldLabel

public final void setFieldLabel(String fieldName,
 String label)

Set label for a specific field. Label will be set only if the field has a setLabel(String) method.

Parameters:

fieldName - Name of the field for which label needs to be set

label - Label to set

setFieldLabel

public final void setFieldLabel(com.vaadin.flow.component.HasValue<?,?> field,
 String label)

Set label for a specific field. Label will be set only if the field has a setLabel(String) method.

Parameters:

field - Field for which label needs to be set

label - Label to set

getFieldLabel

public final String getFieldLabel(String fieldName)

Get label for the given field.

Parameters:

fieldName - Name of the field

Returns:

Label string if "getLabel" method exists in the field, otherwise null.

getFieldLabel

public final String getFieldLabel(com.vaadin.flow.component.HasValue<?,?> field)

Get label for the given field.

Parameters:

field - Field

Returns:

Label string if "getLabel" method exists in the field, otherwise null.

connect

public boolean connect(String... fieldNames)

Connect fields so that a change in any of it is propagated to others within that connected group.

Parameters:

fieldNames - Fields to connect.

Returns:

True if connection is established successfully.

connect

public boolean connect(com.vaadin.flow.component.HasValue<?,?>... fields)

Connect fields so that a change in any of it is propagated to others within that connected group.

Parameters:

fields - Fields to connect.

Returns:

True if connection is established successfully.

connect

public boolean connect(Collection<com.vaadin.flow.component.HasValue<?,?>> fields)

Connect fields so that a change in any of it is propagated to others within that connected group.

Parameters:

fields - Fields to connect.

Returns:

True if connection is established successfully.

setView

public void setView(View view)

Set an associated view for this form.

Parameters:

view - View

getView

public View getView()

Get the associated view of this form.

Returns:

View.

createObjectInstance

protected D createObjectInstance()

Create an instance of the data object. Default implementation tries to invoke the default constructor to create an instance.

Returns:

Newly created data object.

getObject

public D getObject()

Get the instance of the currently editing data object. (A new data object will be created by invoking createObjectInstance() if there is no current object instance set).

Returns:

Instance of the currently loaded object.

getObject

public D getObject(boolean create)

Get the instance of the currently editing data object. A new data object will be created by invoking createObjectInstance() if there is no current object instance set and the parameter passed is true.

Parameters:

create - Whether to create a new instance or not

Returns:

Instance of the currently loaded object.

setObject

public void setObject(D object)

Set the current object. Fields will be loaded.

Parameters:

object - Object to set

setObject

public void setObject(D object,
 boolean load)

Set the current object. Fields will be loaded.

Parameters:

object - Object to set

load - Whether to load the fields or not