ej.widget.basic

Class Button

java.lang.Object

ej.mwt.Widget

ej.widget.StyledWidget

ej.widget.basic.Label

ej.widget.basic.Button

All Implemented Interfaces:

Renderable, Element, StyledRenderable

public class Button
extends Label

A button is a widget that displays a text and reacts to click events.

This example shows a simple button:

 Button button = new Button("Press Me");
 

This example shows a styled button:

 Button button = new Button("Press Me");

 EditableStyle buttonStyle = new EditableStyle();
 buttonStyle.setBackgroundColor(Colors.SILVER);
 buttonStyle.setBorder(new SimpleRectangularBorder(1));
 buttonStyle.setFontProfile(new FontProfile("", 23, Font.STYLE_PLAIN));
 button.mergeStyle(buttonStyle);
 

This example shows a styled button with its background color changing on a press action:

 Button button = new Button("Press Me");

 Stylesheet stylesheet = StyleHelper.getStylesheet();

 EditableStyle buttonStyle = new EditableStyle();
 buttonStyle.setBackgroundColor(Colors.SILVER);
 buttonStyle.setBorder(new SimpleRectangularBorder(1));
 buttonStyle.setFontProfile(new FontProfile("", 23, Font.STYLE_PLAIN));
 stylesheet.addRule(new TypeSelector(Button.class), buttonStyle);

 EditableStyle pressedButtonStyle = new EditableStyle();
 pressedButtonStyle.setBackgroundColor(Colors.GRAY);
 stylesheet.addRule(new AndCombinator(new TypeSelector(Button.class), new StateSelector(State.Active)),
                pressedButtonStyle);
 

Since:

2.3.0

Field Summary

Fields inherited from interface ej.style.Element

EMPTY_ELEMENT_ARRAY

Constructor Summary

Constructors

Constructor and Description
Button() Creates a button with an empty text.
Button(java.lang.String text) Creates a button with the given text to display.

Method Summary

Modifier and Type	Method and Description
void	addOnClickListener(OnClickListener listener) Adds a listener on the click events of the button.
boolean	handleEvent(int event) Called by the system if the widget is the owner of the focus of the active panel.
boolean	isInState(State state) Gets whether or not the element is in the given state.
protected void	onClick() Invoked when the button has been clicked.
void	performClick() Performs the actions associated to a click.
void	removeOnClickListener(OnClickListener listener) Removes a listener on the click events of the button.

Methods inherited from class ej.widget.basic.Label

getText, renderContent, setText, updateText, validateContent

Methods inherited from class ej.widget.StyledWidget

addClassSelector, contains, gainFocus, getAttribute, getChild, getChildrenCount, getChildrenElements, getContentBounds, getParentElement, getStyle, hasClassSelector, isTransparent, lostFocus, mergeStyle, removeAllClassSelectors, removeClassSelector, removeInstanceStyle, render, setClassSelectors, setEnabled, updateStyle, updateStyleOnly, validate

Methods inherited from class ej.mwt.Widget

getAbsoluteX, getAbsoluteX, getAbsoluteY, getAbsoluteY, getEventHandler, getHeight, getPanel, getParent, getPreferredHeight, getPreferredWidth, getRelativeX, getRelativeY, getWidgetAt, getWidth, getX, getY, hasFocus, hideNotify, invalidate, isEnabled, isShown, isValid, isVisible, repaint, repaint, requestFocus, requestFocus, revalidate, revalidateSubTree, setBounds, setEventHandler, setLocation, setPreferredSize, setSize, setVisible, showNotify

Methods inherited from class java.lang.Object

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

Methods inherited from interface ej.mwt.Renderable

getEventHandler, getHeight, getWidth, getX, getY, hideNotify, isShown, repaint, repaint, setEventHandler, showNotify

Constructor Detail

Button

public Button()

Creates a button with an empty text.

Button

public Button(java.lang.String text)

Creates a button with the given text to display. The text cannot be null.

Parameters:

text - the text to display.

Throws:

java.lang.NullPointerException - if the text is null.

Method Detail

onClick

protected void onClick()

Invoked when the button has been clicked.

performClick

public void performClick()

Performs the actions associated to a click.

addOnClickListener

public void addOnClickListener(OnClickListener listener)

Adds a listener on the click events of the button.

Parameters:

listener - the listener to add.

Throws:

java.lang.NullPointerException - if the given listener is null.

removeOnClickListener

public void removeOnClickListener(OnClickListener listener)

Removes a listener on the click events of the button.

Parameters:

listener - the listener to remove.

isInState

public boolean isInState(State state)

Description copied from interface: Element

Gets whether or not the element is in the given state.

Specified by:

isInState in interface Element

Overrides:

isInState in class StyledWidget

Parameters:

state - the state to check.

Returns:

true if the element is in the given state, false otherwise.

handleEvent

public boolean handleEvent(int event)

Description copied from class: Widget

Called by the system if the widget is the owner of the focus of the active panel.

If an event handler is registered, its EventHandler#handleEvent(int) method is called.
Otherwise, do nothing and return false (do not consume event).

Specified by:

handleEvent in interface Renderable

Overrides:

handleEvent in class Widget

Parameters:

event - the event to handle.

Returns:

true if the widget has consumed the event, false otherwise.

See Also:

Widget.setEventHandler(EventHandler)