Question

我有一组按钮，按下时某些按钮被禁用。按钮有各自的图标。然而，麻烦的是当我点击btnAdd时，按钮被禁用，btnAdd的图像不会改变。我正在使用Java Netbeans 8.0.2，我连接到MySql。

我问我如何在执行actionperform时使btnAdd处理第二张图像

这是代码

if(btnAdd.getText().equals("Add")){
btnAdd.setText("Save");
        btnDelete.setEnabled(true);
            btnEdit.setEnabled(false);
                btnExit.setEnabled(false);
                    btnSwitch.setEnabled(false);
                        btnCancel.setEnabled(true);
}else{
    btnAdd.setText("Add");
            btnAdd.setEnabled(true); 
                btnEdit.setEnabled(true);
                    btnDelete.setEnabled(true); 
                        btnSwitch.setEnabled(true);
                            btnCancel.setEnabled(false);
                                btnExit.setEnabled(true);

}

Answer 1

我问我如何在执行actionperform时使btnAdd处理第二张图像？

在这种情况下，解决方案是根据我的评论 - 在JButton上调用setIcon(newImageIcon)，您想要更改其图像。如果您的按钮使用了操作，您还可以通过LARGE_ICON_KEY更改操作的putValue(LARGE_ICON_KEY, newImageIcon)属性。

例如：

import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.util.HashMap;
import java.util.Map;
import javax.swing.*;

public class MultipleButtons extends JPanel {
   private static final long serialVersionUID = 1L;
   private JButton btnSaveAdd = new JButton();
   private JButton btnDelete = new JButton("Delete");
   private JButton btnEdit = new JButton("Edit");
   private JButton btnExit = new JButton("Exit");
   private JButton btnSwitch = new JButton("Switch");
   private JButton btnCancel = new JButton("Cancel");
   private JButton[] btns = {btnSaveAdd, btnDelete, btnEdit, btnExit, btnSwitch, btnCancel};

   public MultipleButtons() {
      Icon saveIcon = UIManager.getIcon("FileView.floppyDriveIcon");

      // wouldn't really use this icon but just used as an example
      Icon addIcon = UIManager.getIcon("OptionPane.warningIcon");

      SaveAction saveAction = new SaveAction("Save", saveIcon);
      AddAction addAction = new AddAction("Add", addIcon);

      saveAction.setNextAction(addAction);
      addAction.setNextAction(saveAction);

      saveAction.buttonMapPut(btnDelete, true);
      saveAction.buttonMapPut(btnEdit, true);
      saveAction.buttonMapPut(btnExit, true);
      saveAction.buttonMapPut(btnSwitch, true);
      saveAction.buttonMapPut(btnCancel, false);

      addAction.buttonMapPut(btnDelete, true);
      addAction.buttonMapPut(btnEdit, false);
      addAction.buttonMapPut(btnExit, false);
      addAction.buttonMapPut(btnSwitch, false);
      addAction.buttonMapPut(btnCancel, true);

      btnSaveAdd.setAction(addAction);

      setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
      setLayout(new GridLayout(1, 0, 5, 5));
      for (JButton jButton : btns) {
         add(jButton);
      }
   }

   private static void createAndShowGui() {
      MultipleButtons mainPanel = new MultipleButtons();

      JFrame frame = new JFrame("MultipleButtons");
      frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
      frame.getContentPane().add(mainPanel);
      frame.pack();
      frame.setLocationByPlatform(true);
      frame.setVisible(true);
   }

   public static void main(String[] args) {
      SwingUtilities.invokeLater(new Runnable() {
         public void run() {
            createAndShowGui();
         }
      });
   }
}

// parent class for both SaveAction and AddAction
abstract class SaveAddAction extends AbstractAction {
   private static final long serialVersionUID = 1L;
   private Map<AbstractButton, Boolean> buttonMap = new HashMap<>(); 
   private Action nextAction; // swap to this Action

   public SaveAddAction(String name, Icon icon) {
      super(name, icon);
      int mnemonic = (int) name.charAt(0);
      putValue(MNEMONIC_KEY, mnemonic);
   }

   public void buttonMapPut(AbstractButton key, Boolean value) {
      buttonMap.put(key, value);
   }

   public void setNextAction(Action nextAction) {
      this.nextAction = nextAction;
   }

   public void setButtonsEnabled(ActionEvent e) {
      AbstractButton source = (AbstractButton) e.getSource();
      if (nextAction != null) {
         source.setAction(nextAction);
      }
      for (AbstractButton button : buttonMap.keySet()) {
         button.setEnabled(buttonMap.get(button));
      }
   }
}

class AddAction extends SaveAddAction {
   private static final long serialVersionUID = 1L;

   public AddAction(String name, Icon icon) {
      super(name, icon);
   }

   @Override
   public void actionPerformed(ActionEvent e) {
      setButtonsEnabled(e);
      // TODO: code for adding goes here
   }

}

class SaveAction extends SaveAddAction {
   private static final long serialVersionUID = 1L;

   public SaveAction(String name, Icon icon) {
      super(name, icon);
   }

   @Override
   public void actionPerformed(ActionEvent e) {
      setButtonsEnabled(e);
      // TODO: code for saving goes here
   }

}

按下图像时jButton第二张图像没有变化

1 个答案: