Question

我不明白如何添加简单的图像。我导入了所有内容并按照他们在此页面上的说法进行操作：

http://www.java2s.com/Code/Java/JavaFX/LoadajpgimagewithImageanduseImageViewtodisplay.htm

Javafx代码

import javafx.application.Application;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class test extends Application {

    @Override
    public void start(Stage stage) {
        stage.setTitle("HTML");
        stage.setWidth(500);
        stage.setHeight(500);
        Scene scene = new Scene(new Group());
        VBox root = new VBox();    

        final ImageView selectedImage = new ImageView();   
        Image image1 = new Image(test.class.getResourceAsStream("C:\\Users\\user\\Desktop\\x.jpg"));

        selectedImage.setImage(image1);

        root.getChildren().addAll(selectedImage);

        scene.setRoot(root);

        stage.setScene(scene);
        stage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
}

错误

    at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$156(LauncherImpl.java:182)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException: Input stream must not be null
    at javafx.scene.image.Image.validateInputStream(Image.java:1110)
    at javafx.scene.image.Image.<init>(Image.java:694)
    at prototype.test.start(test.java:23)
    at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$163(LauncherImpl.java:863)
    at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$176(PlatformImpl.java:326)
    at com.sun.javafx.application.PlatformImpl.lambda$null$174(PlatformImpl.java:295)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.application.PlatformImpl.lambda$runLater$175(PlatformImpl.java:294)
    at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
    at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
    at com.sun.glass.ui.win.WinApplication.lambda$null$149(WinApplication.java:191)

Answer 1

Class.getResourceAsStream尝试在类路径中加载一个元素。它并不意味着加载文件，除非它们包含在类路径中。要在类路径之外加载文件，请改用FileInputStream：

REGISTER 'smsiuc_udf.py' using streaming_python as smsiuc_udfs;
cdrs = load '2016040111*' USING PigStorage('|','-tagFile') ;

mastergtrec = load 'master.txt' USING PigStorage(',','-tagFile');

mastergt = FOREACH mastergtrec GENERATE (chararray) UPPER($1) as opcdpc, (chararray) UPPER($2) as gtoptname,(chararray) UPPER($3) as gtoptcircle;

mastergttup = FOREACH mastergt generate TOTUPLE(opcdpc,gtoptname,gtoptcircle) as mstgttup;

cdrrecord = FOREACH cdrs GENERATE (chararray) UPPER($1) as aparty, (chararray) UPPER($2) as bparty,$3 as smssentdate,$4 as smssenttime,($29=='6' ? 'S' : 'F') as status,(chararray) UPPER($26) as srcgt,(chararray) UPPER($27) as destgt,($12=='405899136999995' ? 'MTSDEL-CDMA' : ($12=='919875089998' ? 'MTSRAJ-GSM' : ($12=='405899150999995' ? 'MTSCHN-CDMA' : $12) ) ) as smscgt, (chararray)$0 as cdrfname,(chararray) $13 as prepost;

filteredp2pcdrs = FILTER cdrrecord by smsiuc_udfs.pullp2pcdrs(aparty,bparty,srcgt,destgt) and status == 'S' and SUBSTRING(smssentdate,4,6) == '$MON';

groupp2pcdrs = GROUP filteredp2pcdrs by (srcgt,destgt,aparty,bparty,smscgt,status,prepost);

distinctp2pcdrs= FOREACH groupp2pcdrs {
uniq = DISTINCT filteredp2pcdrs.(srcgt,destgt,aparty,bparty,smscgt,status,prepost);
GENERATE FLATTEN(group),COUNT(uniq) as cnt;
};

p2preportmap = FOREACH distinctp2pcdrs GENERATE smsiuc_udfs.p2preport(srcgt,destgt,aparty,bparty,mastergttup ),smscgt,status,prepost,cnt

或者使用Image(String) constructor并传递文件的Image image1 = new Image(new FileInputStream("C:\\Users\\user\\Desktop\\x.jpg"));：

URL

Answer 2

尝试将图片添加到GridPane

ImageView img1 = new ImageView(new 
Image(getClass().getResourceAsStream("C:\\Users\\user\\Desktop\\x.jpg")));
    GridPane.setConstraints(img1, 0, 4);

Answer 3

您的问题似乎就是这一行：

Image image1 = new Image(test.class.getResourceAsStream("C:\\Users\\user\\Desktop\\x.jpg"));

因为你得到一个NullPointerException：java.lang.NullPointerException: Input stream must not be null。

请参阅：

Answer 4

我认为解决此问题的一个好方法是将图像拖到项目文件夹中。这样您就可以单独搜索名称

Image image1 = new Image(test.class.getResourceAsStream("x.jpg"));

如果这样做，则添加文件：

Answer 5

正如fabian所提到的，Class.getResourceAsStream(...)从类路径加载InputStream（意思是从jar文件本身）。要从您的计算机加载文件，您只需使用file协议并提供Image构造函数的路径，如下所示：

Image image1 = new Image("file:///C:/Users/user/Desktop/x.jpg");

你得到的原因：

Caused by: java.lang.NullPointerException: Input stream must not be null

错误中的

是因为Class.getResourceAsStream(...)只是在找不到您要求其查找的资源时返回null。 Image构造函数正在接收null，然后抛出异常。

Answer 6

Your problem is at line getResourceAsStream("C:\\Users\\user\\Desktop\\x.jpg")); 替换＆＃34; \\＆＃34;到＆＃34; /＆＃34;，你的问题解决了

在Javafx中添加图像的最简单方法？

6 个答案: