To create a button, you can instantiate one of the many classes that descend from the Show
Note: If you want to collect a group of buttons into a row or column, then you should check out tool bars. First, this section explains the basic button API that How to Use the Common Button APIHere is a picture of an application that displays three buttons: Try this:
As the When a button is disabled, the look and feel automatically generates the button's disabled appearance. However, you could provide an image to be substituted for the normal image. For example, you could provide gray versions of the images used in the left and right buttons. How you implement event handling depends on the type of button you use and how you use it. Generally, you implement an action listener, which is notified every time the user clicks the button. For check boxes you usually use an item listener, which is notified when the check box is selected or deselected. Below is the code from //In initialization code: ImageIcon leftButtonIcon = createImageIcon("images/right.gif"); ImageIcon middleButtonIcon = createImageIcon("images/middle.gif"); ImageIcon rightButtonIcon = createImageIcon("images/left.gif"); b1 = new JButton("Disable middle button", leftButtonIcon); b1.setVerticalTextPosition(AbstractButton.CENTER); b1.setHorizontalTextPosition(AbstractButton.LEADING); //aka LEFT, for left-to-right locales b1.setMnemonic(KeyEvent.VK_D); b1.setActionCommand("disable"); b2 = new JButton("Middle button", middleButtonIcon); b2.setVerticalTextPosition(AbstractButton.BOTTOM); b2.setHorizontalTextPosition(AbstractButton.CENTER); b2.setMnemonic(KeyEvent.VK_M); b3 = new JButton("Enable middle button", rightButtonIcon); //Use the default text position of CENTER, TRAILING (RIGHT). b3.setMnemonic(KeyEvent.VK_E); b3.setActionCommand("enable"); b3.setEnabled(false); //Listen for actions on buttons 1 and 3. b1.addActionListener(this); b3.addActionListener(this); b1.setToolTipText("Click this button to disable " + "the middle button."); b2.setToolTipText("This middle button does nothing " + "when you click it."); b3.setToolTipText("Click this button to enable the " + "middle button."); ... } public void actionPerformed(ActionEvent e) { if ("disable".equals(e.getActionCommand())) { b2.setEnabled(false); b1.setEnabled(false); b3.setEnabled(true); } else { b2.setEnabled(true); b1.setEnabled(true); b3.setEnabled(false); } } protected static ImageIcon createImageIcon(String path) { java.net.URL imgURL = ButtonDemo.class.getResource(path); ...//error handling omitted for clarity... return new ImageIcon(imgURL); } How to Use JButton FeaturesOrdinary buttons — At most one button in a top-level container can be the default button. The default button typically has a highlighted appearance and acts clicked whenever the top-level container has the keyboard focus and the user presses the Return or Enter key. Here is a picture of a dialog, implemented in the ListDialog example, in which the Set button is the default button: You set the default button by invoking the
//In the constructor for a JDialog subclass: getRootPane().setDefaultButton(setButton); The exact implementation of the default button feature depends on the look and feel. For example, in the Windows look and feel, the default button changes to whichever button has the focus, so that pressing Enter clicks the focused button. When no button has the focus, the button you originally specified as the default button becomes the default button again. How to Use Check BoxesThe Check boxes are similar to radio buttons but their selection model is different, by convention. Any number of check boxes in a group — none, some, or all — can be selected. A group of radio buttons, on the other hand, can have only one button selected. Here is a picture of an application that uses four check boxes to customize a cartoon: Try this:
A check box generates one item event and one action event per click. Usually, you listen only for item events, since they let you determine whether the click selected or
deselected the check box. Below is the code from //In initialization code: chinButton = new JCheckBox("Chin"); chinButton.setMnemonic(KeyEvent.VK_C); chinButton.setSelected(true); glassesButton = new JCheckBox("Glasses"); glassesButton.setMnemonic(KeyEvent.VK_G); glassesButton.setSelected(true); hairButton = new JCheckBox("Hair"); hairButton.setMnemonic(KeyEvent.VK_H); hairButton.setSelected(true); teethButton = new JCheckBox("Teeth"); teethButton.setMnemonic(KeyEvent.VK_T); teethButton.setSelected(true); //Register a listener for the check boxes. chinButton.addItemListener(this); glassesButton.addItemListener(this); hairButton.addItemListener(this); teethButton.addItemListener(this); ... public void itemStateChanged(ItemEvent e) { ... Object source = e.getItemSelectable(); if (source == chinButton) { //...make a note of it... } else if (source == glassesButton) { //...make a note of it... } else if (source == hairButton) { //...make a note of it... } else if (source == teethButton) { //...make a note of it... } if (e.getStateChange() == ItemEvent.DESELECTED) //...make a note of it... ... updatePicture(); } How to Use Radio ButtonsRadio buttons are groups of buttons in which, by convention, only one button at a time can be selected. The Swing release supports radio buttons with the Because Here is a picture of an application that uses five radio buttons to let you choose which kind of pet is displayed: Try this:
Each time the user clicks a radio button (even if it was already selected), the button fires an action event. One or two item events also occur — one from the button that was just selected, and another from the button that lost the selection (if any). Usually, you handle radio button clicks using an action listener. Below is the code from
//In initialization code: //Create the radio buttons. JRadioButton birdButton = new JRadioButton(birdString); birdButton.setMnemonic(KeyEvent.VK_B); birdButton.setActionCommand(birdString); birdButton.setSelected(true); JRadioButton catButton = new JRadioButton(catString); catButton.setMnemonic(KeyEvent.VK_C); catButton.setActionCommand(catString); JRadioButton dogButton = new JRadioButton(dogString); dogButton.setMnemonic(KeyEvent.VK_D); dogButton.setActionCommand(dogString); JRadioButton rabbitButton = new JRadioButton(rabbitString); rabbitButton.setMnemonic(KeyEvent.VK_R); rabbitButton.setActionCommand(rabbitString); JRadioButton pigButton = new JRadioButton(pigString); pigButton.setMnemonic(KeyEvent.VK_P); pigButton.setActionCommand(pigString); //Group the radio buttons. ButtonGroup group = new ButtonGroup(); group.add(birdButton); group.add(catButton); group.add(dogButton); group.add(rabbitButton); group.add(pigButton); //Register a listener for the radio buttons. birdButton.addActionListener(this); catButton.addActionListener(this); dogButton.addActionListener(this); rabbitButton.addActionListener(this); pigButton.addActionListener(this); ... public void actionPerformed(ActionEvent e) { picture.setIcon(new ImageIcon("images/" + e.getActionCommand() + ".gif")); } For each group of radio buttons, you need to create a You should generally initialize a group of radio buttons so that one is selected. However, the API doesn't enforce this rule — a group of radio buttons can have no initial selection. Once the user has made a selection, exactly one button is selected from then on. The Button APIThe following tables list the
commonly used button-related API. Other methods you might call, such as The API for using buttons falls into these categories:
Examples that Use Various Kinds of ButtonsThe following examples use buttons. Also see Examples that Use Tool Bars, which lists programs that add
You can learn more about JavaFX button components from the following documents:
Which of the following form controls is used to display data on a form or to accept data from a user?A macro is used to display or accept data for a field with a Yes/No data type.
When working with forms which of the following views would you use to view the completed structure of the form so you can modify any aspect of the form?Layout view and Design view are the two views in which you can make design changes to forms.
Which of the following is useful when you want to organize and summarize you data?Which of the following is useful when you want to organize and summarize you data? To organize controls vertically on a form, use a tabular layout.
Which of the following views is a more visually oriented mode you can use to alter the design of a report and see the effects of the changes in real time?When viewing a report, Design view is a more visually-oriented mode you can use to alter the design of a report and see the effects of the changes in real time.
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