JavaFX 使用实例

附上官方例子：http://docs.oracle.com/javase/8/javafx/sample-apps/

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package login;

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Insets;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.PasswordField;
import javafx.scene.control.TextField;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.HBox;
import javafx.scene.paint.Color;
import javafx.scene.text.Font;
import javafx.scene.text.FontWeight;
import javafx.scene.text.Text;
import javafx.stage.Stage;
import javax.swing.JOptionPane;

/**
 *
 * @author Administrator
 */
public class Login extends Application {

    @Override
    public void start(Stage primaryStage) throws Exception {

        String title = "javafx welcome to login! h=" + String.valueOf((int) primaryStage.getHeight()) + ",w=" + String.valueOf((int) primaryStage.getWidth());
        System.out.println(title);
        System.out.println(primaryStage.getWidth());
        if (Double.isNaN(primaryStage.getHeight())) {
            System.out.println("is nan");
        } else {
            System.out.println("not is nan");
        }
        //primaryStage.setWidth(500);
        // primaryStage.setHeight(500);
        primaryStage.setTitle(title);

        GridPane gridPane = new GridPane();
        gridPane.setAlignment(Pos.CENTER);
        gridPane.setHgap(10);
        gridPane.setVgap(10);
        gridPane.setPadding(new Insets(25, 25, 25, 25));
        Scene scene = new Scene(gridPane, 300, 300);
        primaryStage.setScene(scene);

        Text sceneTitle = new Text("Welcome");
        sceneTitle.setFont(Font.font("Tahoma", FontWeight.NORMAL, 20));
        gridPane.add(sceneTitle, 0, 0, 2, 1);

        Label userName = new Label("User Name:");
        gridPane.add(userName, 0, 1);

      final  TextField userTextField = new TextField();
        gridPane.add(userTextField, 1, 1);

        Label pw = new Label("Password:");
        gridPane.add(pw, 0, 2);

      final  PasswordField pwdBox = new PasswordField();
        gridPane.add(pwdBox, 1, 2);

        Button btn = new Button("Sign in");
        HBox hbBtn = new HBox(10);
        hbBtn.setAlignment(Pos.BOTTOM_RIGHT);
        hbBtn.getChildren().add(btn);
        gridPane.add(hbBtn, 1, 4);

        final Text actiontarget = new Text();
        gridPane.add(actiontarget, 1, 6);

        btn.setOnAction(new EventHandler<ActionEvent>() {
            @Override
            public void handle(ActionEvent e) {
                actiontarget.setFill(Color.FIREBRICK);
                actiontarget.setText("Sign in button pressed");
                String userString=userTextField.getText();
                String passwordString=pwdBox.getText();
                
                if(userString!=null && userString.equals("admin")&&passwordString!=null&&passwordString.equals("123456"))
                {
                    JOptionPane.showMessageDialog(null, "登陆成功！");
                }else{
                     JOptionPane.showMessageDialog(null, "登陆失败，账号密码不正确！");
                }
            }
        });

        primaryStage.show();

    }

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

}