javafx : File Chooser

1.Main.java

import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.stage.Stage;
import javafx.scene.Parent;
import javafx.scene.Scene;


public class Main extends Application {
	@Override
	public void start(Stage primaryStage) {
		try {
			Parent root = FXMLLoader.load(getClass().getResource("Main.fxml"));
			Scene scene = new Scene(root,600,400);
			scene.getStylesheets().add(getClass().getResource("application.css").toExternalForm());
			primaryStage.setScene(scene);
			primaryStage.show();
		} catch(Exception e) {
			e.printStackTrace();
		}
	}
	
	public static void main(String[] args) {
		launch(args);
	}
}

2.Main.fxml

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.control.Button?>
<?import javafx.scene.control.ListView?>
<?import javafx.scene.layout.AnchorPane?>


<AnchorPane minHeight="400.0" prefWidth="600.0" xmlns:fx="http://javafx.com/fxml/1" xmlns="http://javafx.com/javafx/9.0.1" fx:controller="application.MainController">
   <children>
      <Button fx:id="btn1" layoutX="108.0" layoutY="82.0" mnemonicParsing="false" onAction="#Button1Action" text="Select One File" />
      <Button fx:id="btn2" layoutX="108.0" layoutY="175.0" mnemonicParsing="false" onAction="#Button2Action" text="Select Multi Files" />
      <ListView fx:id="listview" layoutX="259.0" layoutY="32.0" prefHeight="342.0" prefWidth="293.0" />
   </children>
</AnchorPane>

3.MainController.java

import java.io.File;
import java.util.List;

import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.scene.control.Button;
import javafx.scene.control.ListView;
import javafx.stage.FileChooser;
import javafx.stage.FileChooser.ExtensionFilter;

public class MainController {
	@FXML
	public Button btn1, btn2;
	@FXML
	public ListView listview;
	
	/**
	 * select single pdf file
	 */
	public void Button1Action(ActionEvent event) {
		FileChooser fc = new FileChooser();
		// if we want to open fixed location
		//fc.setInitialDirectory(new File("D:\\\\Books"));
		
		// if we want to fixed file extension
		fc.getExtensionFilters().addAll(new ExtensionFilter("PDF Files", "*.pdf"));
		File selectedFile = fc.showOpenDialog(null);
		
		if(selectedFile != null) {
			listview.getItems().add(selectedFile.getAbsolutePath());
		}else {
			System.out.println("File is not valid!");
		}
	}
	
	/**
	 * Select multiple files
	 */
	public void Button2Action(ActionEvent event) {
		FileChooser fc = new FileChooser();
		
		List<File> selectedFiles = fc.showOpenMultipleDialog(null);
		
		if(selectedFiles != null) {
			for(int i=0; i<selectedFiles.size(); i++) {
				listview.getItems().add(selectedFiles.get(i).getAbsolutePath());
			}
		}else {
			System.out.println("File is not valid!");
		}
	}
}

Thanks for sharing these amazing lines of File-Choosing code. It was truly useful for my project. Thanks again.