Question

您好，我正在玩Arduino：D

我有serialEvent

    public synchronized void serialEvent(SerialPortEvent oEvent) {
    if (oEvent.getEventType() == SerialPortEvent.DATA_AVAILABLE) {
        try {
            String inputLine = input.readLine();
            System.out.println(inputLine);

        } catch (Exception e) {
            System.err.println(e.toString());
        }
    }
}

如何在JLabel中显示文本的代码（java swing）

lblText.setText(inputLine.toString());

但我有错误inputLine cannot be resolved

Answer 1

inputLine无法解析，因为它是从scope访问的。在类级别范围内声明inputLine而不是方法级范围来解决您的问题。
您可以使用lblTxt方法和searialEvent(...)方法访问initialize()，这样也必须属于班级范围。

上下文中的简短示例：

... //Imports and package declaration

public class ArduinoGUI implements SerialPortEventListener {

    private String inputLine;
    private JLabel lblTxt;

    ... //Other private variables, initialize2(), and close()

    public synchronized void serialEvent(SerialPortEvent oEvent) {
        if(oEvent.getEventType() == SerialPortEvent.DATA_AVAILABLE) {
            try {
                inputLine = input.readLine(); //Don't forget to use the                             
                                              //class-level scope variable here
                System.out.println(inputLine);
                lblTxt.setText(inputLine); //.toString() unnessesary since 
                                           //inputLine is a String
        } catch (Exception e) {
            System.err.println(e.toString());
        }
    }

    ... //Main method and constructor

    private void initialize() {
        ... //GUI stuff
        lblTxt = new JLabel("txt"); //Don't forget to use the 
                                    //class-level scope variable here too
        ... //Adding lblTxt to frame
        lblTxt.setText(inputLine); //Again, .toString() unnessesary
    }
}

在JLabel中显示serialEvent

1 个答案: