How to add or change a shortcut on JMenuItem?

Question

I need to add a shortcut on the right side of JMenuItem , as shown below:

I have an application that uses Ctrl + + and Ctrl + - to enlarge an image. However, the default + key (without Shift ) is the = key. When I try to add accelerators for these menu items, the shortcut Ctrl + - appears as "Ctrl + Minus" (I would prefer "Ctrl"), and the shortcut Ctrl + + appears as "Ctrl + Equals" (even worse - in the interests of the user, I would prefer "Ctrl +"):

 menuBar_view_zoomIn.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_EQUALS, ActionEvent.CTRL_MASK)); 

I want Ctrl + + to appear as "Ctrl +" and Ctrl + - to display as "Ctrl -". How can I do that?

Answer 1

not the answer you need to find

• paint () to heavy, paintComponent () for lightweight JPopup, JMenu (for custom coloring, you can switch to isHeavyWeight ...)

• put JLabel in a container (some questions about JTable by @Guillaume Polet and @Robin)

• create your own JMenu / JPopup (see my comment on your question)

 import java.awt.Color; import java.awt.Component; import java.awt.Dimension; import java.awt.FlowLayout; import java.awt.Graphics; import java.awt.Insets; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.WindowAdapter; import java.awt.event.WindowEvent; import javax.swing.Icon; import javax.swing.JButton; import javax.swing.JComboBox; import javax.swing.JComponent; import javax.swing.JFrame; import javax.swing.JMenu; import javax.swing.JMenuBar; import javax.swing.JMenuItem; import javax.swing.JPanel; import javax.swing.SwingConstants; import javax.swing.UIManager; import javax.swing.border.EtchedBorder; import javax.swing.border.TitledBorder; import javax.swing.plaf.basic.BasicArrowButton; public class ComboBoxMenuExample extends JFrame { public ComboBoxMenuExample() { super("ComboBoxMenu Example"); String[] itemStr = {"name", "Red", "Blue", "number", "255,0,0", "0,0,255", /*separator*/ "system", "control", "controlHighlight", "controlShadow", "text"}; JMenuItem[] menuItems = new JMenuItem[7]; menuItems[0] = new JMenuItem(itemStr[1]); menuItems[1] = new JMenuItem(itemStr[2]); menuItems[2] = new JMenuItem(itemStr[4]); menuItems[3] = new JMenuItem(itemStr[5]); menuItems[4] = new JMenuItem(itemStr[8]); menuItems[5] = new JMenuItem(itemStr[9]); menuItems[6] = new JMenuItem(itemStr[10]); JMenu[] menus = new JMenu[4]; menus[0] = new JMenu(itemStr[0]); menus[1] = new JMenu(itemStr[3]); menus[2] = new JMenu(itemStr[6]); menus[3] = new JMenu(itemStr[7]); menus[0].add(menuItems[0]); menus[0].add(menuItems[1]); menus[1].add(menuItems[2]); menus[1].add(menuItems[3]); menus[3].add(menuItems[4]); menus[3].add(menuItems[5]); menus[2].add(menus[3]); menus[2].add(menuItems[6]); JMenu menu = ComboMenuBar.createMenu(menuItems[0].getText()); menu.add(menus[0]); menu.add(menus[1]); menu.addSeparator(); menu.add(menus[2]); ComboMenuBar comboMenu = new ComboMenuBar(menu); JComboBox combo = new JComboBox(); combo.addItem(itemStr[1]); combo.addItem(itemStr[2]); combo.addItem(itemStr[4]); combo.addItem(itemStr[5]); combo.addItem(itemStr[8]); combo.addItem(itemStr[9]); combo.addItem(itemStr[10]); getContentPane().setLayout(new FlowLayout()); getContentPane().add(new ComboPanel("Fake ComboBox", comboMenu)); getContentPane().add(new ComboPanel("ComboBox", combo)); } class ComboPanel extends JPanel { ComboPanel(String title, JComponent c) { setLayout(new FlowLayout()); setBorder(new TitledBorder(title)); add(c); } } public static void main(String args[]) { try { UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel"); } catch (Exception evt) { } ComboBoxMenuExample frame = new ComboBoxMenuExample(); frame.addWindowListener(new WindowAdapter() { @Override public void windowClosing(WindowEvent e) { System.exit(0); } }); frame.setSize(370, 100); frame.setVisible(true); } } class ComboMenuBar extends JMenuBar { JMenu menu; Dimension preferredSize; public ComboMenuBar(JMenu menu) { this.menu = menu; Color color = UIManager.getColor("Menu.selectionBackground"); UIManager.put("Menu.selectionBackground", UIManager.getColor("Menu.background")); UIManager.put("Menu.selectionBackground", color); menu.updateUI(); MenuItemListener listener = new MenuItemListener(); setListener(menu, listener); add(menu); } class MenuItemListener implements ActionListener { @Override public void actionPerformed(ActionEvent e) { JMenuItem item = (JMenuItem) e.getSource(); menu.setText(item.getText()); menu.requestFocus(); } } private void setListener(JMenuItem item, ActionListener listener) { if (item instanceof JMenu) { JMenu menu1 = (JMenu) item; int n = menu1.getItemCount(); for (int i = 0; i < n; i++) { setListener(menu1.getItem(i), listener); } } else if (item != null) { // null means separator item.addActionListener(listener); } } public String getSelectedItem() { return menu.getText(); } @Override public void setPreferredSize(Dimension size) { preferredSize = size; } @Override public Dimension getPreferredSize() { if (preferredSize == null) { Dimension sd = super.getPreferredSize(); Dimension menuD = getItemSize(menu); Insets margin = menu.getMargin(); Dimension retD = new Dimension(menuD.width, margin.top + margin.bottom + menuD.height); menu.setPreferredSize(retD); preferredSize = retD; } return preferredSize; } private Dimension getItemSize(JMenu menu) { Dimension d = new Dimension(0, 0); int n = menu.getItemCount(); for (int i = 0; i < n; i++) { Dimension itemD; JMenuItem item = menu.getItem(i); if (item instanceof JMenu) { itemD = getItemSize((JMenu) item); } else if (item != null) { itemD = item.getPreferredSize(); } else { itemD = new Dimension(0, 0); // separator } d.width = Math.max(d.width, itemD.width); d.height = Math.max(d.height, itemD.height); } return d; } public static class ComboMenu extends JMenu { ArrowIcon iconRenderer; public ComboMenu(String label) { super(label); iconRenderer = new ArrowIcon(SwingConstants.SOUTH, true); setBorder(new EtchedBorder()); setIcon(new BlankIcon(null, 11)); setHorizontalTextPosition(JButton.LEFT); setFocusPainted(true); } @Override public void paintComponent(Graphics g) { super.paintComponent(g); Dimension d = this.getPreferredSize(); int x = Math.max(0, d.width - iconRenderer.getIconWidth() - 3); int y = Math.max(0, (d.height - iconRenderer.getIconHeight()) / 2 - 2); iconRenderer.paintIcon(this, g, x, y); } } public static JMenu createMenu(String label) { return new ComboMenu(label); } } class ArrowIcon implements Icon, SwingConstants { private static final int DEFAULT_SIZE = 11; //private static final int DEFAULT_SIZE = 5; private int size; private int iconSize; private int direction; private boolean isEnabled; private BasicArrowButton iconRenderer; public ArrowIcon(int direction, boolean isPressedView) { this(DEFAULT_SIZE, direction, isPressedView); } public ArrowIcon(int iconSize, int direction, boolean isEnabled) { this.size = iconSize / 2; this.iconSize = iconSize; this.direction = direction; this.isEnabled = isEnabled; iconRenderer = new BasicArrowButton(direction); } @Override public void paintIcon(Component c, Graphics g, int x, int y) { iconRenderer.paintTriangle(g, x, y, size, direction, isEnabled); } @Override public int getIconWidth() { //int retCode; switch (direction) { case NORTH: case SOUTH: return iconSize; case EAST: case WEST: return size; } return iconSize; } @Override public int getIconHeight() { switch (direction) { case NORTH: case SOUTH: return size; case EAST: case WEST: return iconSize; } return size; } } class BlankIcon implements Icon { private Color fillColor; private int size; public BlankIcon() { this(null, 11); } public BlankIcon(Color color, int size) { //UIManager.getColor("control") //UIManager.getColor("controlShadow") fillColor = color; this.size = size; } @Override public void paintIcon(Component c, Graphics g, int x, int y) { if (fillColor != null) { g.setColor(fillColor); g.drawRect(x, y, size - 1, size - 1); } } @Override public int getIconWidth() { return size; } @Override public int getIconHeight() { return size; } }