javafx - 如何在窗格javafx中居中节点

Question

我如何创建一个窗格并将一个孩子Node放在中心？

让我们说Paneis 500by500和 the Nodeis an ImageViewwith a 200by200 Image

ImageView view = new ImageView();

Image img = new Image("test.png");
view.setImage(img);
Pane pane = new Pane();
pane.setMinWidth(500);
pane.setMinHeight(500);
pane.getChildren().add(view);

Answer 1

you have 2 choices :

1. For example using StackPane instead of Pane (because you can use Pos)

   StackPane p = new StackPane();
   p.setPrefSize(700,700); //set a default size for your stackpane
   Image img = new Image("test.png"); //create an image
   ImageView v = new ImageView(img); //create an imageView and pass the image 
   
   p.getChildren().add(v); //add imageView to stackPane
   StackPane.setAlignment(v,Pos.CENTER_LEFT); //set it to the Center Left(by default it's on the center)
   stage.setScene(new Scene(p));
   stage.show();
   

2. You can use JavaFx Scene Builder, it's a visual layout tool for JavaFx. For example if I want to create a Hbox layout:

   <?xml version="1.0" encoding="UTF-8"?>
   
       <?import java.lang.*?>
       <?import java.net.*?>
       <?import java.util.*?>
       <?import javafx.geometry.*?>
       <?import javafx.scene.*?>
       <?import javafx.scene.control.*?>
       <?import javafx.scene.effect.*?>
       <?import javafx.scene.image.*?>
       <?import javafx.scene.layout.*?>
       <?import javafx.scene.shape.*?>
       <?import javafx.scene.text.*?>
   
       <HBox alignment="CENTER" prefHeight="369.0" prefWidth="425.0" xmlns:fx="http://javafx.com/fxml/1" xmlns="http://javafx.com/javafx/2.2" >
           <children>
               <ImageView fitHeight="150.0" fitWidth="200.0" pickOnBounds="true" preserveRatio="true" x="0.0" HBox.hgrow="NEVER">
                   <image>
                       <Image url="@../yourImg.png" />
                   </image>
               </ImageView>
           </children>
       </HBox>
   

   save-it as myLayout.fxml inside your main class and add following to your code:

   Hbox root = FXMLLoader.load(getClass().getResource("myLayout.fxml"));
   Scene scene = new Scene(root);
   stage.setScene(scene);
   stage.show();
   

Answer 2

我通常使用以下方法将节点/窗格居中：

<VBox alignment="CENTER">
    <HBox alignment="CENTER">
        <!-- your node/pane -->
    </HBox>
</VBox>