Java JFrame,错误无法对非静态字段进行静态引用
我试图从SerialRead方法设置数据变量,但我得到“无法对非静态字段Etiqueta2进行静态引用”,Eclipse说我应该将Etiqueta2设置为静态,但它没有在Jlabel中显示数据Java JFrame,错误无法对非静态字段进行静态引用,java,eclipse,swing,compiler-errors,jframe,Java,Eclipse,Swing,Compiler Errors,Jframe,我试图从SerialRead方法设置数据变量,但我得到“无法对非静态字段Etiqueta2进行静态引用”,Eclipse说我应该将Etiqueta2设置为静态,但它没有在Jlabel中显示数据 public class Final extends JFrame { //Crea Elementos de la interfaz JLabel Etiqueta=new JLabel(); JTextField Texto=new JTextField(); JBu
public class Final extends JFrame
{
//Crea Elementos de la interfaz
JLabel Etiqueta=new JLabel();
JTextField Texto=new JTextField();
JButton Boton=new JButton();
JLabel Etiqueta1=new JLabel();
JLabel Etiqueta2=new JLabel();
JButton Boton1=new JButton();
public Final()
{
super();
// Crea la interfaz
setVisible(true);
setLayout(null);
setTitle("Lectura y escritura de datos");
setSize(380,200);
//Propiedades de los elementos del Frame
// Etiqueta
Etiqueta.setBounds(20,50, 100, 20);
Etiqueta.setText("Enviar un digito");
add(Etiqueta);
// Caja de texto
Texto.setBounds(120,50,100, 20);
add(Texto);
// Boton
Boton.setBounds(250,50,100, 20);
Boton.setText("Enviar");
add(Boton);
// Etiqueta 1
Etiqueta1.setBounds(20,80, 100, 20);
Etiqueta1.setText("Leer un digito");
add(Etiqueta1);
// Etiqueta2
Etiqueta2.setBounds(120,80,100, 20);
add(Etiqueta2);
// Boton 1
Boton1.setBounds(250,80,100, 20);
Boton1.setText("Leer");
add(Boton1);
// Boton de cierre
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
}
void connect ( String portName ) throws Exception
{
CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier(portName);
if ( portIdentifier.isCurrentlyOwned() )
{
System.out.println("Error: Port is currently in use");
}
else
{
CommPort commPort = portIdentifier.open(this.getClass().getName(),2000);
if ( commPort instanceof SerialPort )
{
SerialPort serialPort = (SerialPort) commPort;
serialPort.setSerialPortParams(9600,SerialPort.DATABITS_8,SerialPort.STOPBITS_1,SerialPort.PARITY_NONE);
InputStream in = serialPort.getInputStream();
OutputStream out = serialPort.getOutputStream();
new SerialReader(in, Etiqueta2).execute();
(new Thread(new SerialWriter(out))).start();
}
else
{
System.out.println("Error: Only serial ports are handled by this example.");
}
}
}
/** */
public static class SerialReader extends SwingWorker<Void, String> { //Final frame = new Final();
private InputStream in;
private JLabel label;
public SerialReader(InputStream in, JLabel label) {
this.in = in;
this.label = label;
}
@Override
protected void process(List<String> chunks) {
String data = chunks.get(chunks.size() - 1);
label.setText(data);
}
@Override
protected Void doInBackground() throws Exception {
byte[] buffer = new byte[1024];
int len = -1;
while ((len = this.in.read(buffer)) > -1) {
String data = new String(buffer, 0, len);
System.out.println(data);
publish(data);
}
return null;
}
}
/** */
public static class SerialWriter implements Runnable
{
**** output code ****
}
public static void main ( String[] args )
{
try
{
(new Final()).connect("COM7");
}
catch ( Exception e )
{
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
public类最终扩展JFrame
{
//克里亚国际酒店
JLabel Etiqueta=新的JLabel();
JTextField Texto=新的JTextField();
JButton-Boton=新JButton();
JLabel Etiqueta1=新的JLabel();
JLabel Etiqueta2=新的JLabel();
JButton Boton1=新JButton();
公开决赛()
{
超级();
//克里亚拉因弗塔兹酒店
setVisible(真);
setLayout(空);
setTitle(“曼陀斯学院”);
设置大小(380200);
//框架构件设计方案
//艾蒂克塔
立根(20,50,100,20);
Etiqueta.setText(“Enviar un digito”);
添加(Etiqueta);
//德克托咖啡馆
文本立根(120,50100,20);
添加(Texto);
//波顿
波顿立根数(250,50100,20);
Boton.setText(“Enviar”);
添加(Boton);
//Etiqueta 1
Etiqueta1.立根(20,80,100,20);
Etiqueta1.setText(“Leer un digito”);
添加(Etiqueta1);
//Etiqueta2
Etiqueta2.挫折(120,80100,20);
添加(Etiqueta2);
//波顿1号
Boton1.立根(250,80100,20);
Boton1.setText(“Leer”);
添加(Boton1);
//博顿·德·西尔
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
}
void connect(字符串portName)引发异常
{
CommPortIdentifier portIdentifier=CommPortIdentifier.getPortIdentifier(端口名);
if(portIdentifier.isCurrentlyOwned())
{
System.out.println(“错误:端口当前正在使用”);
}
其他的
{
CommPort CommPort=portIdentifier.open(this.getClass().getName(),2000);
if(串行端口的commPort实例)
{
SerialPort SerialPort=(SerialPort)commPort;
serialPort.setSerialPortParams(9600,serialPort.DATABITS_8,serialPort.STOPBITS_1,serialPort.PARITY_NONE);
InputStream in=serialPort.getInputStream();
OutputStream out=serialPort.getOutputStream();
新的SerialReader(in,Etiqueta2.execute();
(新线程(新SerialWriter(out))).start();
}
其他的
{
System.out.println(“错误:本例只处理串行端口。”);
}
}
}
/** */
公共静态类SerialReader扩展SwingWorker{//Final frame=new Final();
私有输入流;
私人标签;
public SerialReader(InputStream-in,JLabel标签){
this.in=in;
this.label=标签;
}
@凌驾
受保护的无效进程(列表块){
字符串数据=chunks.get(chunks.size()-1);
label.setText(数据);
}
@凌驾
受保护的Void doInBackground()引发异常{
字节[]缓冲区=新字节[1024];
int len=-1;
而((len=this.in.read(buffer))>-1){
字符串数据=新字符串(缓冲区,0,len);
系统输出打印项次(数据);
发布(数据);
}
返回null;
}
}
/** */
公共静态类SerialWriter实现可运行
{
****输出代码****
}
公共静态void main(字符串[]args)
{
尝试
{
(新的Final()).connect(“COM7”);
}
捕获(例外e)
{
//TODO自动生成的捕捉块
e、 printStackTrace();
}
}
}
如何在Etiqueta2标签上设置Text以显示数据变量
谢谢
EDIT3:我用swingworker更新了代码,执行并打印LN以查看控制台中的数据
SerialReader
是Final
的静态内部类,因此无法访问Final
中的任何非静态字段。由于您显然没有在Final
之外使用SerialReader
,所以只需将其设置为非静态(甚至可以是私有的内部类)。这同样适用于SerialWriter
SerialReader
被声明为static
,因此它不能访问外部Final
类的实例字段,因为可以创建SerialReader
的实例,而不需要先创建Final
的实例
相反,您应该将要更新的JLabel
的引用传递给SerialReader
类
public static class SerialReader implements Runnable
{ //Final frame = new Final();
InputStream in;
private JLabel label;
public SerialReader ( InputStream in, JLabel label ) {
this.label = label;
//...
然后,您将使用它从run方法中进行更新
您可以简单地使类非静态,但这取决于您的需要
另一个问题是Swing不是线程安全的,因此实际上不建议从run
方法中调用JLabel
实例上的setText
通常,我建议使用SwingWorker
,因为它有一些方法,允许您发布来自后台线程的结果,并在事件调度线程的上下文中处理这些结果,允许您安全地修改UI的状态,但在这种情况下,您可以使用SwingUtilities.invokeLater
public void run ()
{
//...
try
{
while ( ( len = this.in.read(buffer)) > -1 )
{
//...
SwingUtiltiies.invokeLater(new Runnable() {
public void run() {
Etiqueta2.setText(data);
}
});
}
}
catch ( IOException e )
{
e.printStackTrace();
}
}
但是您可能需要将数据
设置为最终版
,这可能会导致更多问题,在这种情况下,我只需要使用SwingWorker
请仔细查看以了解更多详细信息
SwingWorker
示例。。。
“伪造”InputStream
示例。。。
import java.io.IOException;
导入java.io.InputStream;
导入java.io.OutputStream;
导入java.util.List;
导入java.util.Random;
导入java.util.concurrent.ExecutionException;
导入java。
public static class SerialReader extends SwingWorker<Void, String> { //Final frame = new Final();
private InputStream in;
private JLabel label;
public SerialReader(InputStream in, JLabel label) {
this.in = in;
this.label = label;
}
@Override
protected void process(List<String> chunks) {
String data = chunks.get(chunks.size() - 1);
label.setText(data);
}
@Override
protected Void doInBackground() throws Exception {
byte[] buffer = new byte[1024];
int len = -1;
while ((len = this.in.read(buffer)) > -1) {
String data = new String(buffer, 0, len);
publish(data);
}
return null;
}
}
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridBagLayout;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingWorker;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private JLabel label;
public TestPane() {
setLayout(new GridBagLayout());
label = new JLabel("...");
add(label);
new ClockWorker(label).execute();
}
@Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
public static class ClockWorker extends SwingWorker<Void, String> {
protected static final DateFormat DF = new SimpleDateFormat("hh:mm.ss SSS a");
private JLabel label;
public ClockWorker(JLabel label) {
this.label = label;
}
@Override
protected void process(List<String> chunks) {
label.setText(chunks.get(chunks.size() - 1));
}
@Override
protected Void doInBackground() throws Exception {
while (true) {
publish(DF.format(new Date()));
Thread.sleep(1);
}
}
}
}
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.List;
import java.util.Random;
import java.util.concurrent.ExecutionException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.SwingWorker;
import javax.swing.WindowConstants;
public class Final extends JFrame {
//Crea Elementos de la interfaz
JLabel Etiqueta = new JLabel();
JTextField Texto = new JTextField();
JButton Boton = new JButton();
JLabel Etiqueta1 = new JLabel();
JLabel Etiqueta2 = new JLabel("Banana");
JButton Boton1 = new JButton();
public Final() {
super();
// Crea la interfaz
setVisible(true);
setLayout(null);
setTitle("Lectura y escritura de datos");
setSize(380, 200);
//Propiedades de los elementos del Frame
// Etiqueta
Etiqueta.setBounds(20, 50, 100, 20);
Etiqueta.setText("Enviar un digito");
add(Etiqueta);
// Caja de texto
Texto.setBounds(120, 50, 100, 20);
add(Texto);
// Boton
Boton.setBounds(250, 50, 100, 20);
Boton.setText("Enviar");
add(Boton);
// Etiqueta 1
Etiqueta1.setBounds(20, 80, 100, 20);
Etiqueta1.setText("Leer un digito");
add(Etiqueta1);
// Etiqueta2
Etiqueta2.setBounds(120, 80, 100, 20);
add(Etiqueta2);
// Boton 1
Boton1.setBounds(250, 80, 100, 20);
Boton1.setText("Leer");
add(Boton1);
// Boton de cierre
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
}
void connect(String portName) throws Exception {
System.out.println("...");
new SerialReader(new FakeInputStream(), Etiqueta2).execute();
// CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier(portName);
// if (portIdentifier.isCurrentlyOwned()) {
// System.out.println("Error: Port is currently in use");
// } else {
// CommPort commPort = portIdentifier.open(this.getClass().getName(), 2000);
//
// if (commPort instanceof SerialPort) {
// SerialPort serialPort = (SerialPort) commPort;
// serialPort.setSerialPortParams(9600, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE);
//
// InputStream in = serialPort.getInputStream();
// OutputStream out = serialPort.getOutputStream();
//
// new SerialReader(in, Etiqueta2).execute();
// (new Thread(new SerialWriter(out))).start();
//
// } else {
// System.out.println("Error: Only serial ports are handled by this example.");
// }
// }
}
/**
*
*/
public static class SerialReader extends SwingWorker<Void, String> {
private InputStream in;
private JLabel label;
public SerialReader(InputStream in, JLabel label) {
this.in = in;
this.label = label;
}
@Override
protected void process(List<String> chunks) {
String data = chunks.get(chunks.size() - 1);
label.setText(data);
}
@Override
protected Void doInBackground() throws Exception {
byte[] buffer = new byte[1024];
int len = -1;
while ((len = this.in.read(buffer)) > -1) {
String data = new String(buffer, 0, len);
System.out.println(data);
publish(data);
}
return null;
}
@Override
protected void done() {
try {
get();
} catch (InterruptedException | ExecutionException ex) {
ex.printStackTrace();
}
}
}
public static void main(String[] args) {
try {
(new Final()).connect("COM7");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static class FakeInputStream extends InputStream {
private Random rnd = new Random();
@Override
public int read() throws IOException {
return 33 + rnd.nextInt(125-33); // Ascii characters
}
}
}