java JavaFX |目录选择器类

JavaFX |目录选择器类

原文:https://www . geesforgeks . org/JavaFX-directorychouser-class/

DirectoryChooser 类是 JavaFX 的一部分。目录选择器类显示了一个目录选择器对话框，允许用户选择一个特定的目录。打开目录对话框可能总是导致无操作，即返回空文件。目录选择器类继承对象类。

该类的构造函数:

目录选择器():创建目录选择器的新对象。

常用方法:

方法	说明
getInitialDirectory()	返回目录选择器的初始目录。
getTitle（）	返回目录选择器的标题。
setnitialdirectory(val 文件)	设置属性 initialDirectory 的值
setTitle（String t）	设置目录选择器的标题。
显示对话框(带窗口)	显示新的目录选择对话框。

以下程序说明了目录选择器类的使用:

Java Program to create DirectoryChooser and add it to the stage: In this program we will create a directory chooser named dir_chooser. Create a Label named label and a Button named button. Create an EventHandler to handle the events when the button pressed. When the button pressed, a directory chooser dialog appears and the selected directory is shown as text in the label. Add the label and the button to Vbox and add the VBox to the Scene and add the scene to the stage, and call the show() function to display the final results.

```java // Java Program to create DirectoryChooser // and add it to the stage import javafx.application.Application; import javafx.scene.Scene; import javafx.scene.control.; import javafx.scene.layout.; import javafx.stage.Stage; import javafx.geometry.; import javafx.scene.paint.; import javafx.scene.canvas.; import javafx.scene.text.; import javafx.scene.Group; import javafx.scene.shape.; import javafx.event.ActionEvent; import javafx.event.EventHandler; import javafx.collections.; import java.io.*; import javafx.stage.DirectoryChooser;

public class DirectoryChooser_1 extends Application {

// launch the application     public void start(Stage stage)     {

try {

// set title for the stage             stage.setTitle("DirectoryChooser");

// create a Directory chooser             DirectoryChooser dir_chooser = new DirectoryChooser();

// create a Label             Label label = new Label("no files selected");

// create a Button             Button button = new Button("Show");

// create an Event Handler             EventHandler event =             new EventHandler() {

public void handle(ActionEvent e)                 {

// get the file selected                     File file = dir_chooser.showDialog(stage);

if (file != null) {                         label.setText(file.getAbsolutePath() + " selected");                     }                 }             };

button.setOnAction(event);

// create a VBox             VBox vbox = new VBox(30, label, button);

// set Alignment             vbox.setAlignment(Pos.CENTER);

// create a scene             Scene scene = new Scene(vbox, 800, 500);

// set the scene             stage.setScene(scene);

stage.show();         }

catch (Exception e) {

System.out.println(e.getMessage());         }     }

// Main Method     public static void main(String args[])     {

// launch the application         launch(args);     } } ```

输出:
Java Program to create DirectoryChooser, set title, initial directory and add it to the stage: In this program we will create a directory chooser named dir_chooser. Create a Label named label and a Button named button. Set the title and initial directory of directory chooser using the setTitle() and setInitialDirectory() function. We will create a EventHandler to handle the events when the button is pressed. When the button is pressed a directory chooser dialog appears and the selected directory is shown as text in the label. Add the label and the button to Vbox and add the VBox to the Scene and add the scene to the stage, and call the show() function to display the final results.

```java // Java Program to create DirectoryChooser, // set title, initial directory // and add it to the stage import javafx.application.Application; import javafx.scene.Scene; import javafx.scene.control.; import javafx.scene.layout.; import javafx.stage.Stage; import javafx.geometry.; import javafx.scene.paint.; import javafx.scene.canvas.; import javafx.scene.text.; import javafx.scene.Group; import javafx.scene.shape.; import javafx.event.ActionEvent; import javafx.event.EventHandler; import javafx.collections.; import java.io.*; import javafx.stage.DirectoryChooser;

public class DirectoryChooser_2 extends Application {

// launch the application     public void start(Stage stage)     {

try {

// set title for the stage             stage.setTitle("DirectoryChooser");

// create a Directory chooser             DirectoryChooser dir_chooser =                    new DirectoryChooser();

// set title             dir_chooser.setTitle("Select directory");

// set initial directory             dir_chooser.setInitialDirectory(new File("e:\"));

// create a Label             Label label = new Label("no files selected");

// create a Button             Button button = new Button("Show");

// create an Event Handler             EventHandler event =             new EventHandler() {

public void handle(ActionEvent e)                 {                     // get the file selected                     File file = dir_chooser.showDialog(stage);

if (file != null) {                         label.setText(file.getAbsolutePath() + " selected");                     }                 }             };

button.setOnAction(event);

// create a VBox             VBox vbox = new VBox(30, label, button);

// set Alignment             vbox.setAlignment(Pos.CENTER);

// create a scene             Scene scene = new Scene(vbox, 800, 500);

// set the scene             stage.setScene(scene);

stage.show();         }

catch (Exception e) {

System.out.println(e.getMessage());         }     }

// Main Method     public static void main(String args[])     {

// launch the application         launch(args);     } } ```

输出: