Java Tutorial/Swing/JViewport

Customizing a JViewport Look and Feel

Property StringObject TypeViewport.backgroundColorViewport.fontFontViewport.foregroundColorViewportUIString

Keyboard Movement Control in a JViewport

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Point;
import java.awt.event.ActionEvent;
import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.ActionMap;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.InputMap;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JViewport;
import javax.swing.KeyStroke;
public class MoveViewSample {
  public static final int INCREASE = 0; // direction
  public static final int DECREASE = 1; // direction
  public static final int X_AXIS = 0; // axis
  public static final int Y_AXIS = 1; // axis
  public static final int UNIT = 0; // type
  public static final int BLOCK = 1; // type
  static class MoveAction extends AbstractAction {
    JViewport viewport;
    int direction;
    int axis;
    int type;
    public MoveAction(JViewport viewport, int direction, int axis, int type) {
      if (viewport == null) {
        throw new IllegalArgumentException("null viewport not permitted");
      }
      this.viewport = viewport;
      this.direction = direction;
      this.axis = axis;
      this.type = type;
    }
    public void actionPerformed(ActionEvent actionEvent) {
      Dimension extentSize = viewport.getExtentSize();
      int horizontalMoveSize = 0;
      int verticalMoveSize = 0;
      if (axis == X_AXIS) {
        if (type == UNIT) {
          horizontalMoveSize = 1;
        } else { // type == BLOCK
          horizontalMoveSize = extentSize.width;
        }
      } else { // axis == Y_AXIS
        if (type == UNIT) {
          verticalMoveSize = 1;
        } else { // type == BLOCK
          verticalMoveSize = extentSize.height;
        }
      }
      if (direction == DECREASE) {
        horizontalMoveSize = -horizontalMoveSize;
        verticalMoveSize = -verticalMoveSize;
      }
      // Translate origin by some amount
      Point origin = viewport.getViewPosition();
      origin.x += horizontalMoveSize;
      origin.y += verticalMoveSize;
      // Set new viewing origin
      viewport.setViewPosition(origin);
    }
  }
  public static void main(String args[]) {
    JFrame frame = new JFrame("JViewport Sample");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    Icon icon = new ImageIcon("yourFile.gif");
    JLabel dogLabel = new JLabel(icon);
    JViewport viewport = new JViewport();
    viewport.setView(dogLabel);
    InputMap inputMap = viewport.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW);
    ActionMap actionMap = viewport.getActionMap();
    Action upKeyAction = new MoveAction(viewport, DECREASE, Y_AXIS, UNIT);
    KeyStroke upKey = KeyStroke.getKeyStroke("UP");
    inputMap.put(upKey, "up");
    actionMap.put("up", upKeyAction);
    Action downKeyAction = new MoveAction(viewport, INCREASE, Y_AXIS, UNIT);
    KeyStroke downKey = KeyStroke.getKeyStroke("DOWN");
    inputMap.put(downKey, "down");
    actionMap.put("down", downKeyAction);
    Action leftKeyAction = new MoveAction(viewport, DECREASE, X_AXIS, UNIT);
    KeyStroke leftKey = KeyStroke.getKeyStroke("LEFT");
    inputMap.put(leftKey, "left");
    actionMap.put("left", leftKeyAction);
    Action rightKeyAction = new MoveAction(viewport, INCREASE, X_AXIS, UNIT);
    KeyStroke rightKey = KeyStroke.getKeyStroke("RIGHT");
    inputMap.put(rightKey, "right");
    actionMap.put("right", rightKeyAction);
    Action pgUpKeyAction = new MoveAction(viewport, DECREASE, Y_AXIS, BLOCK);
    KeyStroke pgUpKey = KeyStroke.getKeyStroke("PAGE_UP");
    inputMap.put(pgUpKey, "pgUp");
    actionMap.put("pgUp", pgUpKeyAction);
    Action pgDnKeyAction = new MoveAction(viewport, INCREASE, Y_AXIS, BLOCK);
    KeyStroke pgDnKey = KeyStroke.getKeyStroke("PAGE_DOWN");
    inputMap.put(pgDnKey, "pgDn");
    actionMap.put("pgDn", pgDnKeyAction);
    Action shiftPgUpKeyAction = new MoveAction(viewport, DECREASE, X_AXIS, BLOCK);
    KeyStroke shiftPgUpKey = KeyStroke.getKeyStroke("shift PAGE_UP");
    inputMap.put(shiftPgUpKey, "shiftPgUp");
    actionMap.put("shiftPgUp", shiftPgUpKeyAction);
    Action shiftPgDnKeyAction = new MoveAction(viewport, INCREASE, X_AXIS, BLOCK);
    KeyStroke shiftPgDnKey = KeyStroke.getKeyStroke("shift PAGE_DOWN");
    inputMap.put(shiftPgDnKey, "shiftPgDn");
    actionMap.put("shiftPgDn", shiftPgDnKeyAction);
    frame.add(viewport, BorderLayout.CENTER);
    frame.setSize(300, 200);
    frame.setVisible(true);
  }
}