GWT - ToggleButton Widget


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Introduction

The ToggleButton widget represents a stylish stateful button which allows the user to toggle between up and down states.

Class Declaration

Following is the declaration for com.google.gwt.user.client.ui.ToggleButton class −

public class ToggleButton
   extends CustomButton

CSS Style Rules

Following default CSS Style rules will be applied to all the ToggleButton widget. You can override it as per your requirements.

.gwt-ToggleButton-up {}

.gwt-ToggleButton-down {}

.gwt-ToggleButton-up-hovering {}

.gwt-ToggleButton-down-hovering {}

.gwt-ToggleButton-up-disabled {}

.gwt-ToggleButton-down-disabled {} 

Class Constructors

Sr.No. Constructor & Description
1

ToggleButton()

Constructor for ToggleButton.

2

ToggleButton(Image upImage)

Creates a ToggleButton with up state image.

3

ToggleButton(Image upImage, ClickListener listener)

Creates a ToggleButton with up state image and clickListener.

4

ToggleButton(Image upImage, Image downImage)

Creates a ToggleButton with up state image.

5

ToggleButton(Image upImage, Image downImage, ClickListener listener)

Creates a ToggleButton with up state image.

6

ToggleButton(java.lang.String upText)

Creates a ToggleButton with up state text.

7

ToggleButton(java.lang.String upText, ClickListener listener)

Creates a ToggleButton with up state text and clicklistener.

8

ToggleButton(java.lang.String upText, java.lang.String downText)

Creates a ToggleButton with up state and down state text.

9

ToggleButton(java.lang.String upText, java.lang.String downText, ClickListener listener)

Creates a ToggleButton with up state, down state text and click listener.

Class Methods

Sr.No. Function name & Description
1

boolean isDown()

Is this button down?

2

protected void onClick()

Called when the user finishes clicking on this button.

3

void setDown(boolean down)

Sets whether this button is down.

Methods Inherited

This class inherits methods from the following classes −

  • com.google.gwt.user.client.ui.UIObject

  • com.google.gwt.user.client.ui.Widget

  • com.google.gwt.user.client.ui.FocusWidget

  • com.google.gwt.user.client.ui.CustomWidget

  • java.lang.Object

ToggleButton Widget Example

This example will take you through simple steps to show usage of a ToggleButton Widget in GWT. Follow the following steps to update the GWT application we created in GWT - Create Application chapter −

Step Description
1 Create a project with a name HelloWorld under a package com.tutorialspoint as explained in the GWT - Create Application chapter.
2 Modify HelloWorld.gwt.xml, HelloWorld.css, HelloWorld.html and HelloWorld.java as explained below. Keep rest of the files unchanged.
3 Compile and run the application to verify the result of the implemented logic.

Following is the content of the modified module descriptor src/com.tutorialspoint/HelloWorld.gwt.xml.

<?xml version = "1.0" encoding = "UTF-8"?>
<module rename-to = 'helloworld'>
   <!-- Inherit the core Web Toolkit stuff.                        -->
   <inherits name = 'com.google.gwt.user.User'/>

   <!-- Inherit the default GWT style sheet.                       -->
   <inherits name = 'com.google.gwt.user.theme.clean.Clean'/>

   <!-- Specify the app entry point class.                         -->
   <entry-point class = 'com.tutorialspoint.client.HelloWorld'/>

   <!-- Specify the paths for translatable code                    -->
   <source path = 'client'/>
   <source path = 'shared'/>

</module>

Following is the content of the modified Style Sheet file war/HelloWorld.css.

body {
   text-align: center;
   font-family: verdana, sans-serif;
}

h1 {
   font-size: 2em;
   font-weight: bold;
   color: #777777;
   margin: 40px 0px 70px;
   text-align: center;
}

.gwt-ToggleButton-up {
   color:green;
}

.gwt-ToggleButton-down {
   color:blue;
}

.gwt-ToggleButton-up-hovering {
   color:pink;
}

.gwt-ToggleButton-down-hovering {
   color:aqua;
}

.gwt-ToggleButton-up-disabled {
   color:lime;
}

.gwt-ToggleButton-down-disabled {
   color:maroon;
} 

Following is the content of the modified HTML host file war/HelloWorld.html.

<html>
   <head>
      <title>Hello World</title>
      <link rel = "stylesheet" href = "HelloWorld.css"/>
      <script language = "javascript" src = "helloworld/helloworld.nocache.js">
      </script>
   </head>

   <body>
      <h1>ToggleButton Widget Demonstration</h1>
      <div id = "gwtContainer"></div>
   </body>
</html>

Let us have following content of Java file src/com.tutorialspoint/HelloWorld.java which will demonstrate use of ToggleButton widget.

public class HelloWorld implements EntryPoint {
   public void onModuleLoad() {
	  
      //create toggle buttons
      ToggleButton toggleButton = new ToggleButton("Click Me!");
      ToggleButton toggleButton1 = new ToggleButton("Click Me!");
      
      //disable a toggle button
      toggleButton1.setEnabled(false);
      
      //add a clickListener to the toggle button
      toggleButton.addClickHandler(new ClickHandler() {
        @Override
         public void onClick(ClickEvent event) {
            Window.alert("Hello World!");
         }
      });
	   
      // Add toggle button to the root panel.
      VerticalPanel panel = new VerticalPanel();
      panel.setSpacing(10);            
      panel.add(toggleButton);
      panel.add(toggleButton1);

      RootPanel.get("gwtContainer").add(panel);
   }	
}

Once you are ready with all the changes done, let us compile and run the application in development mode as we did in GWT - Create Application chapter. If everything is fine with your application, this will produce following result −

GWT ToggleButton Widget

When you click Click Me button, it will show an alert message Hello World!

You can see color of button text will change with your interaction.

  • Hover over the button, color will be pink.

  • Press the button, color will be blue.

  • Release the button, button will remain down.


gwt_form_widgets.htm

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