Why do we need swing components? Explain the uses of check boxes and radio buttons in GUI programming.

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 We need the swing component because java Swing Components are essential building blocks for designing, developing, and implementing an application. These components form the Swing Graphical User Interface widget toolkit for the Java programming language.

JRadioButton

The class /RadioButton is an implementation of a radio button- an item that can be selected or deselected, and which displays its state to the user. By default it allows us to select multiple radio buttons. To prevent this, we need to create object of ButtonGroup class and add all radio buttons to in that object. 

Commonly used constructors defined in JRadioButton class are:

• JRadioButton();//creates a radio button with no label

• JRadioButton(String text); //creates a radio button with specified label

• JRadioButton(String text, boolean state); //creates radio button with specified label and state

•  JRadioButton (Icon icn);//creates radio button with specified image icon 

• JRadioButton (Icon icn, boolean state);//creates check box with specified image icon and state

• JRadioButton(String text, Icon icn);//creates radio button with specified image icon and label

• JRadioButton(String text, Icon icn, boolean state); //creates radio button with specified image icon, label, and state;

JButton

The class JButton is an implementation of a push button. This component has a label and generates an event when pressed. It can have Image also.

 Commonly used constructors defined in Button class are:

• JButton();//creates a button with no label

• JButton(String text); //creates a button with specified label

• JButton (Icon icn); //creates button with specified image icon

• JButton(String text, Icon icn); //creates button with specified image icon and label


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