Swing

JRadio Button

Radio button allows user to select only one radio button in each group at a time. If a radio button is selected, whatever the previous radio button is, it will be deselected. To work with radio buttons, we need two classes. First, we create the radio buttons with the JRadioButton class, whose constructors and methods are at the link below
"Swing Method & Constructor Table ." Then we create a group for the buttons with the
ButtonGroup class. We must add the radio button themselves to a panel ( so they are displayed ) and to a button group. Here is the usual way of creating a radio button.

JRadioButton pepsi, coke, tea;

Then in the frame constructor, we call the JRadioButton constructor to create the radio button:

pepsi = new JRadioButton("Pepsi");

Now we would add the radio button to the panel the usual way. Finally, to create a button group to group radio buttons that work together, we would just call the ButtonGroup class constructor.

ButtonGroup group = new ButtonGroup();

Then add the method of the ButtonGroup to add each radio button to the group

group.add(pepsi);
group.add(coke);
group.add(tea);

ClickHere to download RadioButton.java

Check Box

A check box is a control that the user can click to either check or uncheck. Check box is similar to radio buttons, and it's usually used to let the user specify Yes or No to an option. To create a check box, we use the JCheckBox class, then adds it to the panel.

JCheckBox ice_cream, banana, ribs;

The above statement declares the class variable to reference to the check box component. Then we can use the constructor from JCheckBox to create the check boxes and add them to the panel.

ice_cream = new JCheckBox("Ice Cream");

JPanel panel = new JPanel();
panel.add(ice_cream);

Notice that the above statements, we didn't specify which box is initially checked, so as a result they're initially unchecked. If we want to create a check box that is initially checked, we would create a constructor like the following:

ice_Cream = new JCheckBox("Ice Cream", true);

The same idea works with Radio Buttons.
 

ClickHere to download CheckBox.java

The example above are all basic example on how to create JCheckBox and JRadioButton, although it isn't much of a use. Hence, after we learn about different layouts we will see more on how to use JCheckBox and JRadioButtons to do more interesting things.

Borders

A border is a decorative element that visually groups components by drawing a line around them. We can apply a border to any object that inherits JComponent. To create a border we can call one of the static methods from the BorderFactory methods which listed in " Swing Methods & Constructor Table. "

To create a border and add to the panel

JPanel panel = new JPanel();
Border b = BorderFactory.createTitledBorder("Title");
panel.setBorder(b);

Hence, any components we add to the panel appear within this border.

 

It might be a bit hard to notice, but if we look at Title, there is a little faded line with the word "Title" in between the lines.

ClickHere to download BevelBorder.java

Now lets combine JCheckBox, JRadioButton, and BevelBorder together to create a ordering program. It's pretty long so bear with me.

 



 

ClickHere to download Starbucks.java

The above program we created a main panel to hold the JCheckBox and JRadioButton panel. The idea of the above program is to put two panels inside another panel.

Click here to continue

 

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