java Textarea如何在每次循环迭代后追加文本？

Question

我想使用TextArea来记录关于每次迭代后发生的事情的消息。目前，所有日志都已结束循环

@FXML
private TextArea logBookTextArea;

for (Input x : inputList) {

    logBookTextArea.appendText("Czytam " +i+" produkt");
    id = dataDownloader.downloadID(x.getProducer_code());
    writer.print(x.getProduct_code() + ';');
    writer.print("0;");
    writer.print(producentChoiceBox.getSelectionModel().getSelectedItem().toString().toUpperCase() + ";");
    writer.print(x.getProducer_code() + ";");
    writer.print(x.getName() + ";");
    writer.print("Import - bez kategorii;");
    writer.print("4.6;");
    writer.print("20;");
    writeImages(id);
    logBookTextArea.appendText("OK");
    logBookTextArea.appendText("\n");
    i++;
}

Answer 1

我假设您希望创建类似“异步调用”的东西，因为您希望在每次检索列表对象的值时追加数据

你能做什么。正在围绕循环启动一个线程，并将UI更改放在一个平台中。runLater（…）

ExecutorService ex = Executors.newSingleThreadExecutor(r ->{
        Thread t = Executors.defaultThreadFactory().newThread(r);
        t.setDaemon(true);
        return t;
    });

    ex.execute(()-> {
    int i = 0;
    for (Input x : inputList) {
        int index= i;

        //must be declareid here because of lambda rules
        //or put in a container that is effectively final
        Int id = dataDownloader.downloadID(x.getProducer_code());
        writer.print(x.getProduct_code() + ';');
        writer.print("0;");
        writer.print(producentChoiceBox.getSelectionModel().getSelectedItem().toString().toUpperCase() + ";");
        writer.print(x.getProducer_code() + ";");
        writer.print(x.getName() + ";");
        writer.print("Import - bez kategorii;");
        writer.print("4.6;");
        writer.print("20;");
        writeImages(id);
        Platform.runLater(()->{
           logBookTextArea.appendText("Czytam " +index+" );
           logBookTextArea.appendText("OK");
           logBookTextArea.appendText("\n");

        });
        I++
    }
});

Answer 2

我建议你接受@Slaw的建议。使用Timeline

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;
import javafx.animation.KeyFrame;
import javafx.animation.Timeline;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.scene.Scene;
import javafx.scene.control.TextArea;
import javafx.stage.Stage;
import javafx.util.Duration;

/**
 *
 * @author blj0011
 */
public class JavaFXApplication374 extends Application
{
    TextArea textArea = new TextArea();
    List<String> inputList = new ArrayList();
    AtomicInteger counter = new AtomicInteger();

    @Override
    public void start(Stage stage)
    {

        //Add fake data to the list
        for (int i = 0; i < 1000; i++) {
            inputList.add("word ");
        }

        Timeline timeline = new Timeline(new KeyFrame(Duration.seconds(.5), (ActionEvent event) -> {
            textArea.appendText(inputList.get(counter.getAndIncrement()));
        }));
        timeline.setCycleCount(inputList.size());
        timeline.play();

        stage.setScene(new Scene(textArea));
        stage.show();

    }

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args)
    {
        launch(args);
    }

}

这是一个核心重复的问题See