我需要一个屏幕虚拟操纵杆解决方案来控制外部设备 - 购物车。我的程序是用 Java/Swing 编写的，它可以在带有电阻式触摸屏的 Windows 坚固型平板电脑上运行。 Swing 中没有 x-y 滑块控件，无法通过 Google 找到它，所以可能我需要从头开始编写它。现在的问题是：编写此类控件的最佳方法是什么？我正在考虑放置两个 JSlider 控件，一个是水平的，第二个是垂直的，并制作自定义拇指，但我担心这会给我带来麻烦，因为它实际上是一个 hack。也许只是从头开始写？也许有一个现有的解决方案？ 我将通过拇指拖动和触摸最终拇指位置来使用它。
【问题讨论】：
标签： java swing touch 2d joystick
例如
import java.awt.BasicStroke;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.RenderingHints;
import java.awt.Stroke;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class SimpleJoystickDemo extends JFrame {
//I think that orginally made by @HFOE
private int displayWidth = 340;
private int displayHeight = 550;
private final Point position;
public SimpleJoystickDemo() {
super("SimpleJoystickDemo");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(displayWidth, displayHeight);
setLocationRelativeTo(null);
position = new Point();
SimpleJoystick myJoystick = new SimpleJoystick(150, position, 100);
add(myJoystick, BorderLayout.PAGE_END);
Drawing drawing = new Drawing(position);
add(drawing);
}
public static void main(final String[] args) {
Runnable gui = new Runnable() {
@Override
public void run() {
new SimpleJoystickDemo().setVisible(true);
}
};
SwingUtilities.invokeLater(gui);
}
private class Drawing extends JPanel {
private static final long serialVersionUID = 1L;
private final Point position;
public Drawing(Point position) {
this.position = position;
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.setColor(Color.RED);
g2.fillOval(160 + position.x, 160 - position.y, 15, 15);
}
}
}
class SimpleJoystick extends JPanel {
private static final long serialVersionUID = 1L;
//Maximum value for full horiz or vert position where centered is 0:
private int joyOutputRange;
private float joySize; //joystick icon size
private float joyWidth, joyHeight;
private float joyCenterX, joyCenterY; //Joystick displayed Center
//Display positions for text feedback values:
private int textHorizPos, textVertPos;
private int fontSpace = 12;
private float curJoyAngle; //Current joystick angle
private float curJoySize; //Current joystick size
private boolean isMouseTracking;
private boolean leftMouseButton;
private int mouseX, mouseY;
private Stroke lineStroke = new BasicStroke(10, BasicStroke.CAP_ROUND,
BasicStroke.JOIN_ROUND);
private final Point position;
public SimpleJoystick(final int joyOutputRange,
final Point position, final int joySize) {
this.joyOutputRange = joyOutputRange;
this.position = position;
this.joySize = joySize;
joyWidth = joySize;
joyHeight = joyWidth;
setPreferredSize(new Dimension((int) joyWidth + 250,
(int) joyHeight + 80));
joyCenterX = getPreferredSize().width / 2;
joyCenterY = getPreferredSize().height / 2;
this.joySize = joyWidth / 2;
setBackground(new Color(226, 226, 226));
MouseAdapter mouseAdapter = new MouseAdapter() {
@Override
public void mouseMoved(final MouseEvent e) {
mouseCheck(e);
}
@Override
public void mousePressed(final MouseEvent e) {
leftMouseButton = SwingUtilities.isLeftMouseButton(e);
mouseCheck(e);
}
};
addMouseMotionListener(mouseAdapter);
addMouseListener(mouseAdapter);
}
private void mouseCheck(final MouseEvent e) {
mouseX = e.getX();
mouseY = e.getY();
float dx = mouseX - joyCenterX;
float dy = mouseY - joyCenterY;
if (leftMouseButton) {
isMouseTracking = true;
} else {
isMouseTracking = false;
}
if (isMouseTracking) {
curJoyAngle = (float) Math.atan2(dy, dx);
curJoySize = (float) Point.distance(mouseX, mouseY,
joyCenterX, joyCenterY);
} else {
curJoySize = 0;
}
if (curJoySize > joySize) {
curJoySize = joySize;
}
position.x = (int) (joyOutputRange * (Math.cos(curJoyAngle)
* curJoySize) / joySize);
position.y = (int) (joyOutputRange * (-(Math.sin(curJoyAngle)
* curJoySize) / joySize));
SwingUtilities.getRoot(SimpleJoystick.this).repaint();
}
@Override
protected void paintComponent(final Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.setColor(Color.LIGHT_GRAY);
g2.fillOval((int) (joyCenterX - joyWidth / 2),
(int) (joyCenterY - joyHeight / 2),
(int) joyWidth, (int) joyHeight);
//rotate and draw joystick line segment:
Graphics2D g3 = (Graphics2D) g2.create();
g3.translate(joyCenterX, joyCenterY);
g3.rotate(curJoyAngle);
g3.setColor(Color.GRAY);
g3.setStroke(lineStroke);
g3.drawLine(0, 0, (int) curJoySize, 0);
g3.dispose();
//
g2.setColor(Color.GRAY);
g2.fillOval((int) joyCenterX - 10, (int) joyCenterY - 10, 20, 20);
textHorizPos = 50;
textVertPos = (int) (joyCenterY - 50);
g2.drawString("Horizont:", textHorizPos, textVertPos);
textHorizPos += (4 * fontSpace);
g2.drawString(String.valueOf(position.x), textHorizPos, textVertPos);
textHorizPos = 50;
textVertPos += 12;
g2.drawString("Vertical :", textHorizPos, textVertPos);
textHorizPos += (4 * fontSpace);
g2.drawString(String.valueOf(position.y), textHorizPos, textVertPos);
}
}
【讨论】：
来自@tutejszy 的重新编写的代码。删除了警告并添加了缺少的 PointChangeEvent。
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.RenderingHints;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
public class VJoystick extends JPanel implements ChangeListener
{
private JLabel lblPosition;
private static final long serialVersionUID = 1L;
public VJoystick()
{
setLayout(new BorderLayout(0, 0));
SimpleJoystick myJoystick = new SimpleJoystick(150);
myJoystick.setPreferredSize(new Dimension(100,100));
myJoystick.addChangeListener(this);
add(myJoystick, BorderLayout.CENTER);
lblPosition = new JLabel("position");
add(lblPosition, BorderLayout.SOUTH);
}
@Override
public void stateChanged(ChangeEvent ev) {
Point p = null;
try {
p = ((PointChangeEvent)ev).p;
} catch (Exception e) {
return;
}
lblPosition.setText("x="+p.x+" y="+p.y);
}
}
class SimpleJoystick extends JPanel
{
private static final long serialVersionUID = 1L;
/** Maximum value for full horiz or vert position where centered is 0 */
private int joyOutputRange;
/** max x and y value, in pixels */
private int joyRadius;
/** Joystick displayed Center, in pixels */
private int joyCenterX, joyCenterY;
/** joystick output position scaled to given joyOutputRange */
private Point position = new Point();
/** joystick x axis value in pixels */
private int dx = 0;
/** joystick y axis value in pixels */
private int dy = 0;
/**
* @param joyOutputRange
*/
public SimpleJoystick(final int joyOutputRange) {
this.joyOutputRange = joyOutputRange;
setBackground(new Color(226, 226, 226));
MouseAdapter mouseAdapter = new MouseAdapter() {
@Override
public void mousePressed(final MouseEvent e) {
if (SwingUtilities.isLeftMouseButton(e) && cursorChanged(e.getX(), e.getY())) {
SwingUtilities.getRoot(SimpleJoystick.this).repaint();
fireStateChanged();
}
}
@Override
public void mouseDragged(MouseEvent e) {
if (SwingUtilities.isLeftMouseButton(e) && cursorChanged(e.getX(), e.getY())) {
SwingUtilities.getRoot(SimpleJoystick.this).repaint();
fireStateChanged();
}
}
};
addMouseMotionListener(mouseAdapter);
addMouseListener(mouseAdapter);
}
private boolean cursorChanged(int mouseX, int mouseY) {
if (joyRadius == 0) return false;
dx = mouseX - joyCenterX;
dy = mouseY - joyCenterY;
if (dx > joyRadius) dx = joyRadius;
if (dy > joyRadius) dy = joyRadius;
if (dx < -joyRadius) dx = -joyRadius;
if (dy < -joyRadius) dy = -joyRadius;
position.x = joyOutputRange * dx / joyRadius;
position.y = -joyOutputRange * dy / joyRadius;
return true;
}
@Override
protected void paintComponent(final Graphics g) {
super.paintComponent(g);
int joyWidth = getSize().width;
int joyHeight = getSize().height;
joyRadius = Math.min(joyWidth, joyHeight) / 2;
if (joyRadius == 0) return;
joyCenterX = joyWidth / 2;
joyCenterY = joyHeight / 2;
Graphics2D g2 = (Graphics2D) g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
int diameter;
//background
g2.setColor(Color.LIGHT_GRAY);
diameter = joyRadius*2;
g2.fillOval(joyCenterX - diameter/2 , joyCenterY - diameter/2, diameter, diameter);
g2.setColor(Color.RED);
diameter = 40;
g2.fillOval(joyCenterX + dx - diameter/2 , joyCenterY + dy - diameter/2, diameter, diameter);
//thumb
g2.setColor(Color.GRAY);
diameter = 20;
g2.fillOval(joyCenterX - diameter/2 , joyCenterY - diameter/2, diameter, diameter);
}
void addChangeListener(ChangeListener listener) {
listenerList.add(ChangeListener.class, listener);
}
void removeChangeListener(ChangeListener listener) {
listenerList.remove(ChangeListener.class, listener);
}
protected void fireStateChanged() {
ChangeEvent e = new PointChangeEvent(this, position);
Object[] listeners = listenerList.getListenerList();
for (int i = listeners.length - 2; i >= 0; i -= 2) {
if (listeners[i] == ChangeListener.class) {
((ChangeListener) listeners[i + 1]).stateChanged(e);
}
}
}
}
class PointChangeEvent extends ChangeEvent
{
private static final long serialVersionUID = 1L;
public Point p;
public PointChangeEvent(Object source, Point p)
{
super(source);
this.p=p;
}
}
【讨论】：
这是来自@mKorbel 的重新编写的代码，它基于事件且更面向摇摆，没有浮动：
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.RenderingHints;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
class JoyDemo extends JPanel implements ChangeListener {
private JLabel lblPosition;
public JoyDemo() {
setLayout(new BorderLayout(0, 0));
SimpleJoystick myJoystick = new SimpleJoystick(150);
myJoystick.setPreferredSize(new Dimension(100,100));
myJoystick.addChangeListener(this);
add(myJoystick, BorderLayout.CENTER);
lblPosition = new JLabel("position");
add(lblPosition, BorderLayout.SOUTH);
}
@Override
public void stateChanged(ChangeEvent ev) {
Point p = null;
try {
p = ((PointChangeEvent)ev).p;
} catch (Exception e) {
return;
}
lblPosition.setText("x="+p.x+" y="+p.y);
}
}
class SimpleJoystick extends JPanel {
/** Maximum value for full horiz or vert position where centered is 0 */
private int joyOutputRange;
/** max x and y value, in pixels */
private int joyRadius;
/** Joystick displayed Center, in pixels */
private int joyCenterX, joyCenterY;
/** joystick output position scaled to given joyOutputRange */
private Point position = new Point();
/** joystick x axis value in pixels */
private int dx = 0;
/** joystick y axis value in pixels */
private int dy = 0;
/**
* @param joyOutputRange
*/
public SimpleJoystick(final int joyOutputRange) {
this.joyOutputRange = joyOutputRange;
setBackground(new Color(226, 226, 226));
MouseAdapter mouseAdapter = new MouseAdapter() {
@Override
public void mousePressed(final MouseEvent e) {
if (SwingUtilities.isLeftMouseButton(e) && cursorChanged(e.getX(), e.getY())) {
SwingUtilities.getRoot(SimpleJoystick.this).repaint();
fireStateChanged();
}
}
@Override
public void mouseDragged(MouseEvent e) {
if (SwingUtilities.isLeftMouseButton(e) && cursorChanged(e.getX(), e.getY())) {
SwingUtilities.getRoot(SimpleJoystick.this).repaint();
fireStateChanged();
}
}
};
addMouseMotionListener(mouseAdapter);
addMouseListener(mouseAdapter);
}
private boolean cursorChanged(int mouseX, int mouseY) {
if (joyRadius == 0) return false;
dx = mouseX - joyCenterX;
dy = mouseY - joyCenterY;
if (dx > joyRadius) dx = joyRadius;
if (dy > joyRadius) dy = joyRadius;
if (dx < -joyRadius) dx = -joyRadius;
if (dy < -joyRadius) dy = -joyRadius;
position.x = joyOutputRange * dx / joyRadius;
position.y = -joyOutputRange * dy / joyRadius;
return true;
}
@Override
protected void paintComponent(final Graphics g) {
super.paintComponent(g);
int joyWidth = getSize().width;
int joyHeight = getSize().height;
joyRadius = Math.min(joyWidth, joyHeight) / 2;
if (joyRadius == 0) return;
joyCenterX = joyWidth / 2;
joyCenterY = joyHeight / 2;
Graphics2D g2 = (Graphics2D) g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
int diameter;
//background
g2.setColor(Color.LIGHT_GRAY);
diameter = joyRadius*2;
g2.fillOval(joyCenterX - diameter/2 , joyCenterY - diameter/2, diameter, diameter);
g2.setColor(Color.RED);
diameter = 40;
g2.fillOval(joyCenterX + dx - diameter/2 , joyCenterY + dy - diameter/2, diameter, diameter);
//thumb
g2.setColor(Color.GRAY);
diameter = 20;
g2.fillOval(joyCenterX - diameter/2 , joyCenterY - diameter/2, diameter, diameter);
}
void addChangeListener(ChangeListener listener) {
listenerList.add(ChangeListener.class, listener);
}
void removeChangeListener(ChangeListener listener) {
listenerList.remove(ChangeListener.class, listener);
}
protected void fireStateChanged() {
ChangeEvent e = new PointChangeEvent(this, position);
Object[] listeners = listenerList.getListenerList();
for (int i = listeners.length - 2; i >= 0; i -= 2) {
if (listeners[i] == ChangeListener.class) {
((ChangeListener) listeners[i + 1]).stateChanged(e);
}
}
}
}
【讨论】：
这是我的解决方案。请注意，我修改了@Dark.Rider 的答案，谁修改了@tutejszy 的答案，谁修改了@mKorbel 的答案......
我制作了 2 个文件。一个叫 Joystick.java
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.beans.PropertyChangeListener;
import javax.swing.event.SwingPropertyChangeSupport;
import javax.swing.SwingUtilities;
public class Joystick extends javax.swing.JPanel {
private final int outputMax;
private final int thumbDiameter;
private final int thumbRadius;
private final int panelWidth;
private final int arrowRadius;
private final int BORDER_THICKNESS = 2;
private final Point thumbPos = new Point();
protected SwingPropertyChangeSupport propertySupporter = new SwingPropertyChangeSupport(this);
/**
* @param output_max The maximum value to scale output to. If this value was
* 5 and the joystick thumb was dragged to the top-left corner, the output
* would be (-5,5)
* @param panel_width how big the JPanel will be. The sizes of the joystick's
* visual components are proportional to this value
*/
public Joystick(int output_max, int panel_width) {
assert output_max > 0;
assert panel_width > 0;
outputMax = output_max;
panelWidth = panel_width;
thumbDiameter = panel_width/4;
thumbRadius = thumbDiameter/2;
arrowRadius = panel_width/24;
MouseAdapter mouseAdapter = new MouseAdapter() {
private void repaintAndTriggerListeners(){
SwingUtilities.getRoot(Joystick.this).repaint();
propertySupporter.firePropertyChange(null, null, getOutputPos());
}
@Override
public void mousePressed(final MouseEvent e) {
if (SwingUtilities.isLeftMouseButton(e)) {
updateThumbPos(e.getX(), e.getY());
repaintAndTriggerListeners();
}
}
@Override
public void mouseDragged(MouseEvent e) {
if (SwingUtilities.isLeftMouseButton(e)) {
updateThumbPos(e.getX(), e.getY());
repaintAndTriggerListeners();
}
}
@Override
public void mouseReleased(MouseEvent e) {
if (SwingUtilities.isLeftMouseButton(e)) {
centerThumbPad();
repaintAndTriggerListeners();
}
}
};
addMouseMotionListener(mouseAdapter);
addMouseListener(mouseAdapter);
setPreferredSize(new java.awt.Dimension(panel_width, panel_width));
setOpaque(false);
centerThumbPad();
}
private void centerThumbPad(){
thumbPos.x = panelWidth/2;
thumbPos.y = panelWidth/2;
}
/**
* update both thumbPos
* @param mouseX the x position of cursor that has clicked in the joystick panel
* @param mouseY the y position of cursor that has clicked in the joystick panel
* @return
*/
private void updateThumbPos(int mouseX, int mouseY) {
// if the cursor is clicked out of bounds, we'll modify the position
// to be the closest point where we can draw the thumb pad completely
if (mouseX < thumbRadius)
mouseX = thumbRadius;
else if(mouseX > panelWidth - thumbRadius)
mouseX = panelWidth - thumbRadius;
if (mouseY < thumbRadius)
mouseY = thumbRadius;
else if(mouseY > panelWidth - thumbRadius)
mouseY = panelWidth - thumbRadius;
thumbPos.x = mouseX;
thumbPos.y = mouseY;
}
/**
* @return the scaled position of the joystick thumb pad
*/
Point getOutputPos(){
Point result = new Point();
result.x = outputMax * (thumbPos.x - panelWidth/2) / (panelWidth/2-thumbDiameter/2);
result.y = -outputMax * (thumbPos.y - panelWidth/2) / (panelWidth/2-thumbDiameter/2);
return result;
}
@Override
protected void paintComponent(final Graphics g) {
super.paintComponent(g);
//joystick background border
g.setColor(Color.BLACK);
g.fillOval(thumbRadius, thumbRadius, panelWidth-thumbDiameter, panelWidth-thumbDiameter);
//joystick background color
g.setColor(Color.GRAY);
g.fillOval(thumbRadius+BORDER_THICKNESS, thumbRadius+BORDER_THICKNESS, panelWidth-thumbDiameter-BORDER_THICKNESS*2, panelWidth-thumbDiameter-BORDER_THICKNESS*2);
//joystick background arrows
g.setColor(Color.BLACK);
int[] left_x = {thumbDiameter-arrowRadius,thumbDiameter+arrowRadius,thumbDiameter+arrowRadius};
int[] left_y = {panelWidth/2,panelWidth/2+arrowRadius,panelWidth/2-arrowRadius};
g.fillPolygon(left_x, left_y,3);
int[] right_x = {panelWidth-thumbDiameter+arrowRadius,panelWidth-thumbDiameter-arrowRadius,panelWidth-thumbDiameter-arrowRadius};
int[] right_y = {panelWidth/2,panelWidth/2+arrowRadius,panelWidth/2-arrowRadius};
g.fillPolygon(right_x, right_y,3);
int[] up_x = left_y;
int[] up_y = left_x;
g.fillPolygon(up_x, up_y,3);
int[] down_x = right_y;
int[] down_y = right_x;
g.fillPolygon(down_x, down_y,3);
//thumb pad border
g.setColor(Color.BLACK);
g.fillOval(thumbPos.x - thumbRadius - BORDER_THICKNESS, thumbPos.y - thumbRadius - BORDER_THICKNESS, thumbRadius*2+BORDER_THICKNESS*2, thumbRadius*2+BORDER_THICKNESS*2);
//thumb pad color
g.setColor(Color.GRAY);
g.fillOval(thumbPos.x - thumbRadius, thumbPos.y - thumbRadius, thumbRadius*2, thumbRadius*2);
}
@Override
public void addPropertyChangeListener(PropertyChangeListener listener) {
propertySupporter.addPropertyChangeListener(listener);
}
@Override
public void removePropertyChangeListener(PropertyChangeListener listener) {
propertySupporter.removePropertyChangeListener(listener);
}
}
还有一个叫 JoystickOutputContainer.java（用来制作示例图片）
import java.awt.BorderLayout;
import java.awt.Point;
import java.beans.PropertyChangeListener;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class JoystickOutputContainer extends JPanel {
private Joystick myJoystick = new Joystick(100, 140);
private JLabel lblPosition = new JLabel("x=0 y=0");
public JoystickOutputContainer() {
setLayout(new BorderLayout(0, 0));
add(myJoystick, BorderLayout.CENTER);
add(lblPosition, BorderLayout.SOUTH);
myJoystick.addPropertyChangeListener(updateConsoleListener);
}
private final PropertyChangeListener updateConsoleListener = (evt) -> {
updateConsoleCallback( (Point) evt.getNewValue() );
};
private void updateConsoleCallback(Point p){
lblPosition.setText("x="+p.x+" y="+p.y);
}
}
【讨论】：