Java by API/javax.swing/JTextField — различия между версиями

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Текущая версия на 14:18, 31 мая 2010

JTextField: addActionListener(ActionListener s)

 
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class MainClass extends JPanel  implements ActionListener {
  JTextField jtf = new JTextField(15);
  public MainClass() {
 
      add(jtf); 
      jtf.addActionListener(this); 
    } 
   
    // Show text when user presses ENTER. 
    public void actionPerformed(ActionEvent ae) { 
      System.out.println(jtf.getText()); 
    } 
  public static void main(String[] args) {
    JFrame frame = new JFrame();
    frame.getContentPane().add(new MainClass());
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setSize(200, 200);
    frame.setVisible(true);
  }
}





JTextField: addFocusListener(FocusListener l)

 
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import javax.swing.JFrame;
import javax.swing.JTextField;
public class Main {
  public static void main(String[] a) {
    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JTextField textField = new JTextField("A TextField");
    textField.addFocusListener(new FocusListener() {
      public void focusGained(FocusEvent e) {
        displayMessage("Focus gained", e);
      }
      public void focusLost(FocusEvent e) {
        displayMessage("Focus lost", e);
      }
      void displayMessage(String prefix, FocusEvent e) {
        System.out.println(prefix
            + (e.isTemporary() ? " (temporary):" : ":")
            + e.getComponent().getClass().getName()
            + "; Opposite component: "
            + (e.getOppositeComponent() != null ? e.getOppositeComponent().getClass().getName()
                : "null"));
      }
    });
    frame.add(textField,"North");
    frame.add(new JTextField(),"South");
    frame.setSize(300, 200);
    frame.setVisible(true);
  }
}





JTextField: addKeyListener(KeyListener l)

 
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.InputVerifier;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JTextField;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;
import javax.swing.text.BadLocationException;
import javax.swing.text.Document;
import javax.swing.text.JTextComponent;
public class MainClass {
  public static void main(String args[]) throws Exception {
    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JTextField nameTextField = new JTextField();
    frame.add(nameTextField, BorderLayout.NORTH);
    KeyListener keyListener = new KeyListener() {
      public void keyPressed(KeyEvent keyEvent) {
        printIt("Pressed", keyEvent);
      }
      public void keyReleased(KeyEvent keyEvent) {
        printIt("Released", keyEvent);
      }
      public void keyTyped(KeyEvent keyEvent) {
        printIt("Typed", keyEvent);
      }
      private void printIt(String title, KeyEvent keyEvent) {
        int keyCode = keyEvent.getKeyCode();
        String keyText = KeyEvent.getKeyText(keyCode);
        System.out.println(title + " : " + keyText + " / " + keyEvent.getKeyChar());
      }
    };
    nameTextField.addKeyListener(keyListener);

    frame.setSize(250, 100);
    frame.setVisible(true);
  }
}





JTextField: copy()

 
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.event.CaretEvent;
import javax.swing.event.CaretListener;
public class Main {
  JTextField jtf = new JTextField(15);
  JButton jbtnCut = new JButton("Cut");
  JButton jbtnPaste = new JButton("Paste");
  JButton jbtnCopy = new JButton("Copy");
  public Main() {
    JFrame jfrm = new JFrame("Cut, Copy, and Paste");
    jfrm.setLayout(new FlowLayout());
    jfrm.setSize(230, 150);
    jfrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    
    jbtnCut.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent le) {
        jtf.cut();
        update();
      }
    });
    jbtnPaste.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent le) {
        jtf.paste();
        update();
      }
    });
    jbtnCopy.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent le) {
        jtf.copy();
        update();
      }
    });
    jtf.addCaretListener(new CaretListener() {
      public void caretUpdate(CaretEvent ce) {
        update();
      }
    });
    jfrm.add(jtf);
    jfrm.add(jbtnCut);
    jfrm.add(jbtnPaste);
    jfrm.add(jbtnCopy);
    jfrm.setVisible(true);
  }
  private void update() {
    System.out.println("All text: " + jtf.getText());
    if (jtf.getSelectedText() != null)
      System.out.println("Selected text: " + jtf.getSelectedText());
    else
      System.out.println("Selected text: ");
  }
  public static void main(String args[]) {
    new Main();
  }
}





JTextField: cut()

 
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.event.CaretEvent;
import javax.swing.event.CaretListener;
public class Main {
  JTextField jtf = new JTextField(15);
  JButton jbtnCut = new JButton("Cut");
  JButton jbtnPaste = new JButton("Paste");
  JButton jbtnCopy = new JButton("Copy");
  public Main() {
    JFrame jfrm = new JFrame("Cut, Copy, and Paste");
    jfrm.setLayout(new FlowLayout());
    jfrm.setSize(230, 150);
    jfrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    
    jbtnCut.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent le) {
        jtf.cut();
        update();
      }
    });
    jbtnPaste.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent le) {
        jtf.paste();
        update();
      }
    });
    jbtnCopy.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent le) {
        jtf.copy();
        update();
      }
    });
    jtf.addCaretListener(new CaretListener() {
      public void caretUpdate(CaretEvent ce) {
        update();
      }
    });
    jfrm.add(jtf);
    jfrm.add(jbtnCut);
    jfrm.add(jbtnPaste);
    jfrm.add(jbtnCopy);
    jfrm.setVisible(true);
  }
  private void update() {
    System.out.println("All text: " + jtf.getText());
    if (jtf.getSelectedText() != null)
      System.out.println("Selected text: " + jtf.getSelectedText());
    else
      System.out.println("Selected text: ");
  }
  public static void main(String args[]) {
    new Main();
  }
}





JTextField: getActions()

 
import java.awt.BorderLayout;
import java.util.Hashtable;
import javax.swing.Action;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.text.DefaultEditorKit;
public class MainClass {
  public static void main(String args[]) throws Exception {
    JFrame frame = new JFrame("Cut/Paste Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JTextField textField = new JTextField();
    frame.add(textField, BorderLayout.NORTH);
    Action actions[] = textField.getActions();
    Action cutAction = findAction(actions, DefaultEditorKit.cutAction);
    Action copyAction = findAction(actions, DefaultEditorKit.copyAction);
    Action pasteAction = findAction(actions, DefaultEditorKit.pasteAction);
    JPanel panel = new JPanel();
    frame.add(panel, BorderLayout.SOUTH);
    JButton cutButton = new JButton(cutAction);
    cutButton.setText("Cut");
    panel.add(cutButton);
    JButton copyButton = new JButton(copyAction);
    copyButton.setText("Copy");
    panel.add(copyButton);
    JButton pasteButton = new JButton(pasteAction);
    pasteButton.setText("Paste");
    panel.add(pasteButton);
    frame.setSize(250, 250);
    frame.setVisible(true);
  }
  public static Action findAction(Action actions[], String key) {
    Hashtable<Object, Action> commands = new Hashtable<Object, Action>();
    for (int i = 0; i < actions.length; i++) {
      Action action = actions[i];
      commands.put(action.getValue(Action.NAME), action);
    }
    return commands.get(key);
  }
}





JTextField: getCaretPosition()

 
import java.awt.BorderLayout;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.KeyStroke;
import javax.swing.text.BadLocationException;
public class MainClass {
  public static void main(final String args[]) {
    JFrame frame = new JFrame("Popup Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    final JTextField textField = new JTextField();
    frame.add(textField, BorderLayout.NORTH);
    ActionListener actionListener = new ActionListener() {
      public void actionPerformed(ActionEvent actionEvent) {
    
          int dotPosition = textField.getCaretPosition();
          Rectangle popupLocation = null;
          try {
            popupLocation = textField.modelToView(dotPosition);
          } catch (BadLocationException e) {
            e.printStackTrace();
          }
          System.out.println(popupLocation);
      }
    };
    
    
    KeyStroke keystroke =
      KeyStroke.getKeyStroke(KeyEvent.VK_PERIOD, 0, false);
    textField.registerKeyboardAction(actionListener, keystroke,
      JComponent.WHEN_FOCUSED);
    frame.setSize(250, 150);
    frame.setVisible(true);
  }
}





JTextField: getDocument()

 
import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.text.AbstractDocument;
public class Main {
  public static void main(String[] args) {
    JFrame f = new JFrame("Text Field Elements");
    JTextField tf = new JTextField(32);
    tf.setText("That"s one small step for man...");
    f.getContentPane().add(tf);
    f.pack();
    f.setVisible(true);
    ((AbstractDocument) tf.getDocument()).dump(System.out);
  }
}





JTextField: getHorizontalVisibility()

 
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BoundedRangeModel;
import javax.swing.BoxLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollBar;
import javax.swing.JTextField;
public class MainClass {
  public static void main(String args[]) throws Exception {
    JFrame frame = new JFrame("Text Slider");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    
    
    final TextSlider ts = new TextSlider();
    ts.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        System.out.println("Text: " + ts.getText());
      }
    });
    
    
    frame.add(ts, BorderLayout.NORTH);
    frame.setSize(300, 100);
    frame.setVisible(true);
  }
}
class TextSlider extends JPanel {
  private JTextField textField;
  private JScrollBar scrollBar;
  public TextSlider() {
    setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
    textField = new JTextField();
    scrollBar = new JScrollBar(JScrollBar.HORIZONTAL);
    BoundedRangeModel brm = textField.getHorizontalVisibility();
    scrollBar.setModel(brm);
    add(textField);
    add(scrollBar);
  }
  public JTextField getTextField() {
    return textField;
  }
  public String getText() {
    return textField.getText();
  }
  public void addActionListener(ActionListener l) {
    textField.addActionListener(l);
  }
  public void removeActionListener(ActionListener l) {
    textField.removeActionListener(l);
  }
  public JScrollBar getScrollBar() {
    return scrollBar;
  }
}





JTextField: getHorizontalVisibility() (2)

 
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BoundedRangeModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class MainClass {
  public static void main(final String args[]) {
    JFrame frame = new JFrame("Offset Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JPanel panel = new JPanel(new BorderLayout());
    final JTextField textField = new JTextField();
    panel.add(textField, BorderLayout.CENTER);
    frame.add(panel, BorderLayout.NORTH);
    JButton button = new JButton("Get Offset");
    ActionListener actionListener = new ActionListener() {
      public void actionPerformed(ActionEvent actionEvent) {
        System.out.println("Offset: " + textField.getScrollOffset());
        System.out.println("Visibility: " + textField.getHorizontalVisibility());
        BoundedRangeModel model = textField.getHorizontalVisibility();
        int extent = model.getExtent();
        textField.setScrollOffset(extent);
      }
    };
    button.addActionListener(actionListener);
    frame.add(button, BorderLayout.SOUTH);
    frame.setSize(250, 150);
    frame.setVisible(true);
  }
}





JTextField: getInputMap()

 
import java.awt.Event;
import java.awt.event.KeyEvent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.KeyStroke;
import javax.swing.text.DefaultEditorKit;
public class MainClass extends JFrame {
  MainClass(String title) {
    super(title);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JPanel jp = new JPanel();
    JLabel jl = new JLabel("Name:");
    jp.add(jl);
    JTextField jt = new JTextField(20);
    jp.add(jt);
    KeyStroke ks = KeyStroke.getKeyStroke(KeyEvent.VK_B, Event.CTRL_MASK);
    jt.getInputMap().put(ks, DefaultEditorKit.beepAction);
    getContentPane().add(jp);
    pack();
    setVisible(true);
  }
  public static void main(String[] args) {
    new MainClass("Binding Demo2");
  }
}





JTextField: getKeymap()

 
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.KeyStroke;
import javax.swing.text.Keymap;
public class MainClass {
  public static void main(final String args[]) {
    JFrame frame = new JFrame("Default Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JTextField textField = new JTextField();
    frame.add(textField, BorderLayout.NORTH);
    JPanel panel = new JPanel();
    JButton defaultButton = new JButton("Default Button");
    defaultButton.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent actionEvent) {
        System.out.println(actionEvent.getActionCommand() + " selected");
      }
    });
    panel.add(defaultButton);
    JButton otherButton = new JButton("Other Button");
    otherButton.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent actionEvent) {
        System.out.println(actionEvent.getActionCommand() + " selected");
      }
    });
    panel.add(otherButton);
    frame.add(panel, BorderLayout.SOUTH);
    Keymap keymap = textField.getKeymap();
    KeyStroke keystroke = KeyStroke.getKeyStroke(KeyEvent.VK_ENTER, 0, false);
    keymap.removeKeyStrokeBinding(keystroke);
    frame.getRootPane().setDefaultButton(defaultButton);
    frame.setSize(250, 150);
    frame.setVisible(true);
  }
}





JTextField: getScrollOffset()

 
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BoundedRangeModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class MainClass {
  public static void main(final String args[]) {
    JFrame frame = new JFrame("Offset Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JPanel panel = new JPanel(new BorderLayout());
    final JTextField textField = new JTextField();
    panel.add(textField, BorderLayout.CENTER);
    frame.add(panel, BorderLayout.NORTH);
    JButton button = new JButton("Get Offset");
    ActionListener actionListener = new ActionListener() {
      public void actionPerformed(ActionEvent actionEvent) {
        System.out.println("Offset: " + textField.getScrollOffset());
        System.out.println("Visibility: " + textField.getHorizontalVisibility());
        BoundedRangeModel model = textField.getHorizontalVisibility();
        int extent = model.getExtent();
        textField.setScrollOffset(extent);
      }
    };
    button.addActionListener(actionListener);
    frame.add(button, BorderLayout.SOUTH);
    frame.setSize(250, 150);
    frame.setVisible(true);
  }
}





JTextField.LEADING

 
import java.awt.GridLayout;
import javax.swing.JFrame;
import javax.swing.JTextField;
public class MainClass {
  public static void main(final String args[]) {
    JFrame frame = new JFrame("Alignment Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setLayout(new GridLayout(0, 1));
    JTextField textField = new JTextField("Left");
    textField.setHorizontalAlignment(JTextField.LEFT);
    frame.add(textField);
    textField = new JTextField("Center");
    textField.setHorizontalAlignment(JTextField.CENTER);
    frame.add(textField);
    textField = new JTextField("Right");
    textField.setHorizontalAlignment(JTextField.RIGHT);
    frame.add(textField);
    textField = new JTextField("Leading");
    textField.setHorizontalAlignment(JTextField.LEADING);
    frame.add(textField);
    textField = new JTextField("Trailing");
    textField.setHorizontalAlignment(JTextField.TRAILING);
    frame.add(textField);
    frame.pack();
    frame.setSize(250, (int) frame.getSize().getHeight());
    frame.setVisible(true);
  }
}





JTextField.LEFT

 
import java.awt.GridLayout;
import javax.swing.JFrame;
import javax.swing.JTextField;
public class MainClass {
  public static void main(final String args[]) {
    JFrame frame = new JFrame("Alignment Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setLayout(new GridLayout(0, 1));
    JTextField textField = new JTextField("Left");
    textField.setHorizontalAlignment(JTextField.LEFT);
    frame.add(textField);
    textField = new JTextField("Center");
    textField.setHorizontalAlignment(JTextField.CENTER);
    frame.add(textField);
    textField = new JTextField("Right");
    textField.setHorizontalAlignment(JTextField.RIGHT);
    frame.add(textField);
    textField = new JTextField("Leading");
    textField.setHorizontalAlignment(JTextField.LEADING);
    frame.add(textField);
    textField = new JTextField("Trailing");
    textField.setHorizontalAlignment(JTextField.TRAILING);
    frame.add(textField);
    frame.pack();
    frame.setSize(250, (int) frame.getSize().getHeight());
    frame.setVisible(true);
  }
}





JTextField: modelToView(int pos)

 
import java.awt.BorderLayout;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.KeyStroke;
import javax.swing.text.BadLocationException;
public class MainClass {
  public static void main(final String args[]) {
    JFrame frame = new JFrame("Popup Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    final JTextField textField = new JTextField();
    frame.add(textField, BorderLayout.NORTH);
    ActionListener actionListener = new ActionListener() {
      public void actionPerformed(ActionEvent actionEvent) {
    
          int dotPosition = textField.getCaretPosition();
          Rectangle popupLocation = null;
          try {
            popupLocation = textField.modelToView(dotPosition);
          } catch (BadLocationException e) {
            e.printStackTrace();
          }
          System.out.println(popupLocation);
      }
    };
    
    
    KeyStroke keystroke =
      KeyStroke.getKeyStroke(KeyEvent.VK_PERIOD, 0, false);
    textField.registerKeyboardAction(actionListener, keystroke,
      JComponent.WHEN_FOCUSED);
    frame.setSize(250, 150);
    frame.setVisible(true);
  }
}





JTextField: paste()

 
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.event.CaretEvent;
import javax.swing.event.CaretListener;
public class Main {
  JTextField jtf = new JTextField(15);
  JButton jbtnCut = new JButton("Cut");
  JButton jbtnPaste = new JButton("Paste");
  JButton jbtnCopy = new JButton("Copy");
  public Main() {
    JFrame jfrm = new JFrame("Cut, Copy, and Paste");
    jfrm.setLayout(new FlowLayout());
    jfrm.setSize(230, 150);
    jfrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    
    jbtnCut.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent le) {
        jtf.cut();
        update();
      }
    });
    jbtnPaste.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent le) {
        jtf.paste();
        update();
      }
    });
    jbtnCopy.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent le) {
        jtf.copy();
        update();
      }
    });
    jtf.addCaretListener(new CaretListener() {
      public void caretUpdate(CaretEvent ce) {
        update();
      }
    });
    jfrm.add(jtf);
    jfrm.add(jbtnCut);
    jfrm.add(jbtnPaste);
    jfrm.add(jbtnCopy);
    jfrm.setVisible(true);
  }
  private void update() {
    System.out.println("All text: " + jtf.getText());
    if (jtf.getSelectedText() != null)
      System.out.println("Selected text: " + jtf.getSelectedText());
    else
      System.out.println("Selected text: ");
  }
  public static void main(String args[]) {
    new Main();
  }
}





JTextField: read(Reader in, Object desc)

 
import java.awt.BorderLayout;
import java.io.FileReader;
import java.io.IOException;
import javax.swing.JFrame;
import javax.swing.JTextField;
public class MainClass {
  public static void main(String args[]) throws Exception {
    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JTextField nameTextField = new JTextField();
    frame.add(nameTextField, BorderLayout.NORTH);
    
    FileReader reader = null;
    try {
      reader = new FileReader("fileName.txt");
      nameTextField.read(reader, "fileName.txt");
    } catch (IOException exception) {
      System.err.println("Load oops");
      exception.printStackTrace();
    } finally {
      if (reader != null) {
        try {
          reader.close();
        } catch (IOException exception) {
          System.err.println("Error closing reader");
          exception.printStackTrace();
        }
      }
    }
    
    frame.setSize(250, 100);
    frame.setVisible(true);
  }
}





JTextField: registerKeyboardAction(ActionListener anAction,String aCommand,KeyStroke aKeyStroke,int aCondition)

 
import java.awt.BorderLayout;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.KeyStroke;
import javax.swing.text.BadLocationException;
public class MainClass {
  public static void main(final String args[]) {
    JFrame frame = new JFrame("Popup Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    final JTextField textField = new JTextField();
    frame.add(textField, BorderLayout.NORTH);
    ActionListener actionListener = new ActionListener() {
      public void actionPerformed(ActionEvent actionEvent) {
    
          int dotPosition = textField.getCaretPosition();
          Rectangle popupLocation = null;
          try {
            popupLocation = textField.modelToView(dotPosition);
          } catch (BadLocationException e) {
            e.printStackTrace();
          }
          System.out.println(popupLocation);
      }
    };
    
    
    KeyStroke keystroke =
      KeyStroke.getKeyStroke(KeyEvent.VK_PERIOD, 0, false);
    textField.registerKeyboardAction(actionListener, keystroke,
      JComponent.WHEN_FOCUSED);
    frame.setSize(250, 150);
    frame.setVisible(true);
  }
}





JTextField: requestFocus()

 
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
public class Main {
  public static void main(String[] argv) throws Exception {
    final JTextField textfield = new JTextField(10);
    SwingUtilities.invokeLater(new Runnable() {
      public void run() {
        textfield.requestFocus();
      }
    });
  }
}





JTextField: setDocument(Document doc)

 

import java.awt.FlowLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.PlainDocument;
class JTextFieldLimit extends PlainDocument {
  private int limit;
  JTextFieldLimit(int limit) {
    super();
    this.limit = limit;
  }
  JTextFieldLimit(int limit, boolean upper) {
    super();
    this.limit = limit;
  }
  public void insertString(int offset, String str, AttributeSet attr) throws BadLocationException {
    if (str == null)
      return;
    if ((getLength() + str.length()) <= limit) {
      super.insertString(offset, str, attr);
    }
  }
}
public class Main extends JFrame {
  JTextField textfield1;
  JLabel label1;
  public void init() {
    setLayout(new FlowLayout());
    label1 = new JLabel("max 10 chars");
    textfield1 = new JTextField(15);
    add(label1);
    add(textfield1);
    textfield1.setDocument(new JTextFieldLimit(10));
    
    setSize(300,300);
    setVisible(true);
  }
}





JTextField: setFocusAccelerator(char aKey)

 
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.SwingConstants;
public class Main {
  public static void main(String[] args) {
    JLabel l;
    JTextField t;
    JButton b;
    JFrame f = new JFrame("Text Accelerator");
    
    f.add(l = new JLabel("Name:", SwingConstants.RIGHT));
    l.setDisplayedMnemonic("n");
    f.add(l = new JLabel("House/Street:", SwingConstants.RIGHT));
    l.setDisplayedMnemonic("h");
    f.add(l = new JLabel("City:", SwingConstants.RIGHT));
    l.setDisplayedMnemonic("c");
    f.add(l = new JLabel("State/County:", SwingConstants.RIGHT));
    l.setDisplayedMnemonic("s");
    f.add(l = new JLabel("Zip/Post code:", SwingConstants.RIGHT));
    l.setDisplayedMnemonic("z");
    f.add(l = new JLabel("Telephone:", SwingConstants.RIGHT));
    l.setDisplayedMnemonic("t");
    f.add(b = new JButton("Clear"));
    b.setMnemonic("l");
    f.add(t = new JTextField(35));
    t.setFocusAccelerator("n");
    f.add(t = new JTextField(35));
    t.setFocusAccelerator("h");
    f.add(t = new JTextField(35));
    t.setFocusAccelerator("c");
    f.add(t = new JTextField(35));
    t.setFocusAccelerator("s");
    f.add(t = new JTextField(35));
    t.setFocusAccelerator("z");
    f.add(t = new JTextField(35));
    t.setFocusAccelerator("t");
    f.add(b = new JButton("OK"));
    b.setMnemonic("o");
    f.pack();
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.setVisible(true);
  }
}





JTextField: setHorizontalAlignment(int alignment)

 

import javax.swing.JTextField;
public class Main{
  public static void main(String[] argv) {
    JTextField textfield = new JTextField(10);
    textfield.setHorizontalAlignment(JTextField.RIGHT);
  }
}





JTextField: setInputVerifier(InputVerifier input)

 
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.InputVerifier;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JTextField;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;
import javax.swing.text.BadLocationException;
import javax.swing.text.Document;
import javax.swing.text.JTextComponent;
public class MainClass {
  public static void main(String args[]) throws Exception {
    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JTextField nameTextField = new JTextField();
    frame.add(nameTextField, BorderLayout.NORTH);
    frame.add(new JTextField(), BorderLayout.SOUTH);
    InputVerifier verifier = new InputVerifier() {
      public boolean verify(JComponent input) {
        final JTextComponent source = (JTextComponent) input;
        String text = source.getText();
        if ((text.length() != 0) && !(text.equals("Exit"))) {
          JOptionPane.showMessageDialog(source, "Can"t leave.", "Error Dialog",
              JOptionPane.ERROR_MESSAGE);
          return false;
        } else {
          return true;
        }
      }
    };
    nameTextField.setInputVerifier(verifier);
    
    frame.setSize(250, 100);
    frame.setVisible(true);
  }
}





JTextField: setNavigationFilter(NavigationFilter filter)

 
import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.text.NavigationFilter;
import javax.swing.text.Position;
public class MainClass {
  public static void main(String args[]) throws Exception {
    final String START_STRING = "Start\n";
    final int START_STRING_LENGTH = START_STRING.length();
    JFrame frame = new JFrame("Navigation Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JTextArea textArea = new JTextArea(START_STRING);
    textArea.setCaretPosition(START_STRING_LENGTH);
    JScrollPane scrollPane = new JScrollPane(textArea);
    frame.add(scrollPane, BorderLayout.CENTER);
    NavigationFilter filter = new NavigationFilter() {
      public void setDot(NavigationFilter.FilterBypass fb, int dot, Position.Bias bias) {
        if (dot < START_STRING_LENGTH) {
          fb.setDot(START_STRING_LENGTH, bias);
        } else {
          fb.setDot(dot, bias);
        }
      }
      public void moveDot(NavigationFilter.FilterBypass fb, int dot, Position.Bias bias) {
        if (dot < START_STRING_LENGTH) {
          fb.setDot(START_STRING_LENGTH, bias);
        } else {
          fb.setDot(dot, bias);
        }
      }
    };
    textArea.setNavigationFilter(filter);
    frame.setSize(250, 150);
    frame.setVisible(true);
  }
}





JTextField: setPreferredSize(Dimension preferredSize)

 

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class Main {
  public static void main(String[] args) {
    JTextField tf = new JTextField("mm");
    tf.setPreferredSize(tf.getPreferredSize());
    tf.setText("");
    JPanel pHacked = new JPanel();
    pHacked.add(tf);
    JPanel pStock = new JPanel();
    pStock.add(new JTextField(2));
    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setLayout(new java.awt.GridLayout(0, 1));
    frame.add(pHacked);
    frame.add(pStock);
    frame.setSize(150, 150);
    frame.setVisible(true);
    tf.requestFocus();
  }
}





JTextField: setTransferHandler(TransferHandler newHandler)

 
       
/**
 * Demonstrate various aspects of Swing "data transfer".
 * @author Ian Darwin, http://www.darwinsys.ru
 * @author Jonathan Fuerth, http://www.SQLPower.ca
 */       
       
import java.awt.Color;
import java.awt.Container;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JComboBox;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSlider;
import javax.swing.JTextField;
import javax.swing.SwingConstants;
import javax.swing.TransferHandler;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
public class MainClass extends JFrame {
  public static void main(String[] args) {
    new MainClass().setVisible(true);
  }
  private JTextField tf;
  private JLabel l;
  private JComboBox propertyComboBox;
  public MainClass() {
    Container cp = new Box(BoxLayout.X_AXIS);
    setContentPane(cp);
    JPanel firstPanel = new JPanel();
    propertyComboBox = new JComboBox();
    propertyComboBox.addItem("text");
    propertyComboBox.addItem("font");
    propertyComboBox.addItem("background");
    propertyComboBox.addItem("foreground");
    firstPanel.add(propertyComboBox);
    cp.add(firstPanel);
    cp.add(Box.createGlue());
    tf = new JTextField("Hello");
    tf.setForeground(Color.RED);
    tf.setDragEnabled(true);
    cp.add(tf);
    cp.add(Box.createGlue());
    l = new JLabel("Hello");
    l.setBackground(Color.YELLOW);
    cp.add(l);
    cp.add(Box.createGlue());
    JSlider stryder = new JSlider(SwingConstants.VERTICAL);
    stryder.setMinimum(10);
    stryder.setValue(14);
    stryder.setMaximum(72);
    stryder.setMajorTickSpacing(10);
    stryder.setPaintTicks(true);
    cp.add(stryder);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setSize(500, 300);
    setMyTransferHandlers((String) propertyComboBox.getSelectedItem());
    MouseListener myDragListener = new MouseAdapter() {
      public void mousePressed(MouseEvent e) {
        JComponent c = (JComponent) e.getSource();
        TransferHandler handler = c.getTransferHandler();
        handler.exportAsDrag(c, e, TransferHandler.COPY);
      }
    };
    l.addMouseListener(myDragListener);
    propertyComboBox.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent ce) {
        JComboBox bx = (JComboBox) ce.getSource();
        String prop = (String) bx.getSelectedItem();
        setMyTransferHandlers(prop);
      }
    });
    tf.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent evt) {
        JTextField jtf = (JTextField) evt.getSource();
        String fontName = jtf.getText();
        Font font = new Font(fontName, Font.BOLD, 18);
        tf.setFont(font);
      }
    });
    stryder.addChangeListener(new ChangeListener() {
      public void stateChanged(ChangeEvent evt) {
        JSlider sl = (JSlider) evt.getSource();
        Font oldf = tf.getFont();
        Font newf = oldf.deriveFont((float) sl.getValue());
        tf.setFont(newf);
      }
    });
  }
  private void setMyTransferHandlers(String s) {
    TransferHandler th = new TransferHandler(s);
    tf.setTransferHandler(th);
    l.setTransferHandler(th);
  }
}





JTextField.TRAILING

 
import java.awt.GridLayout;
import javax.swing.JFrame;
import javax.swing.JTextField;
public class MainClass {
  public static void main(final String args[]) {
    JFrame frame = new JFrame("Alignment Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setLayout(new GridLayout(0, 1));
    JTextField textField = new JTextField("Left");
    textField.setHorizontalAlignment(JTextField.LEFT);
    frame.add(textField);
    textField = new JTextField("Center");
    textField.setHorizontalAlignment(JTextField.CENTER);
    frame.add(textField);
    textField = new JTextField("Right");
    textField.setHorizontalAlignment(JTextField.RIGHT);
    frame.add(textField);
    textField = new JTextField("Leading");
    textField.setHorizontalAlignment(JTextField.LEADING);
    frame.add(textField);
    textField = new JTextField("Trailing");
    textField.setHorizontalAlignment(JTextField.TRAILING);
    frame.add(textField);
    frame.pack();
    frame.setSize(250, (int) frame.getSize().getHeight());
    frame.setVisible(true);
  }
}





JTextField: write(Writer out)

 
import java.awt.BorderLayout;
import java.io.FileWriter;
import java.io.IOException;
import javax.swing.JFrame;
import javax.swing.JTextField;
public class MainClass {
  public static void main(String args[]) throws Exception {
    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JTextField nameTextField = new JTextField();
    frame.add(nameTextField, BorderLayout.NORTH);
    
    FileWriter writer = null;
    try {
      writer = new FileWriter("filename.txt");
      nameTextField.write(writer);
    } catch (IOException exception) {
      System.err.println("Save oops");
      exception.printStackTrace();
    } finally {
      if (writer != null) {
        try {
          writer.close();
        } catch (IOException exception) {
          System.err.println("Error closing writer");
          exception.printStackTrace();
        }
      }
    }
    
    frame.setSize(250, 100);
    frame.setVisible(true);
  }
}





new JTextField(String text)

 

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class Main {
  public static void main(String[] args) {
    JTextField tf = new JTextField("mm");
    tf.setPreferredSize(tf.getPreferredSize());
    tf.setText("");
    JPanel pHacked = new JPanel();
    pHacked.add(tf);
    JPanel pStock = new JPanel();
    pStock.add(new JTextField(2));
    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setLayout(new java.awt.GridLayout(0, 1));
    frame.add(pHacked);
    frame.add(pStock);
    frame.setSize(150, 150);
    frame.setVisible(true);
    tf.requestFocus();
  }
}





new JTextField(String text, int columns)

 
import javax.swing.*;
import java.awt.*;
public class Main extends JFrame {
  public Main() {
    super("JTextField Test");
    getContentPane().setLayout(new FlowLayout());
    JTextField textField1 = new JTextField("1", 1);
    JTextField textField2 = new JTextField("22", 2);
    JTextField textField3 = new JTextField("333", 3);
    getContentPane().add(textField1);
    getContentPane().add(textField2);
    getContentPane().add(textField3);
    setSize(300, 170);
    setVisible(true);
  }
  public static void main(String argv[]) {
    new Main();
  }
}


Источник — «http://jexp.ru/index.php?title=Java_by_API/javax.swing/JTextField&oldid=644»