java JavaFX - setOnAction 不适用
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JavaFX - setOnAction not applicable
提问by RAP
I am trying to learn JavaFX, and I've written the code shown down below, however I seem to be having trouble with this line of code:
我正在尝试学习 JavaFX，并且我已经编写了如下所示的代码，但是我似乎在使用这行代码时遇到了问题：
btn.setOnAction(new EventHandler<ActionEvent>()
where it underlines setOnAction, and prints this Error:
它在 setOnAction 下划线，并打印此错误：
The method setOnAction(EventHandler<ActionEvent>) in the type ButtonBase is not applicable for the arguments (new EventHandler<ActionEvent>(){})
import java.awt.event.ActionEvent;
import javafx.application.Application;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;
public class Test extends Application{
public static void main(String[] args){
launch(args);
}
@Override
public void start(Stage primaryStage) {
primaryStage.setTitle("Hello World!");
Button btn = new Button();
btn.setText("Say 'Hello World' ");
btn.setOnAction(new EventHandler<ActionEvent>(){
@Override
public void handle(ActionEvent event) {
System.out.println("Button clicked");
}
});
StackPane root = new StackPane();
root.getChildren().add(btn);
primaryStage.setScene(new Scene(root, 300, 250));
primaryStage.show();
}
}
What am I doing wrong?
我究竟做错了什么？
回答by RAP
You have imported awt event listener just change this line of code
您已导入 awt 事件侦听器只需更改这行代码
import java.awt.event.ActionEvent;
with this
有了这个
import javafx.event.ActionEvent;
and you can also use lambda expression like this
你也可以像这样使用 lambda 表达式
btn.setOnAction((event) -> {
System.out.println("Button clicked");
});
回答by Reimeus
You're mixing up Javafx with Swing. Replace
您将 Javafx 与 Swing 混为一谈。代替
import java.awt.event.ActionEvent;
with
和
import javafx.event.ActionEvent;
