Java-Android-FTP上传主线程异常

Question

我正在开发一个非常简单的应用程序，您按下一个按钮，启动相机，您拍摄一张照片，这张照片存储在 SD 卡中，然后上传到我的 FTP。我正在使用 simpleFTP 库连接到我的 FTP，但我不知道为什么在上传文件时出现以下错误。

这是主类代码的相关部分:

private void dispatchTakePictureIntent() {
    Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
        // Create the File where the photo should go
        photoFile = null;
        try {
            photoFile = createImageFile();
            Log.v("photoFile", photoFile.toString());
        } catch (IOException ex) {
            // Error occurred while creating the File

        }
        // Continue only if the File was successfully created
        if (photoFile != null) {
            takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(photoFile));

            startActivityForResult(takePictureIntent, REQUEST_TAKE_PHOTO);
        }
    }

}

private File createImageFile() throws IOException {
    // Create an image file name
    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
    String imageFileName = "JPEG_" + timeStamp + "_";
    File storageDir = Environment.getExternalStoragePublicDirectory(
            Environment.DIRECTORY_PICTURES);
    File image = File.createTempFile(
            imageFileName,  /* prefix */
            ".jpg",         /* suffix */
            storageDir      /* directory */
    );

    // Save a file: path for use with ACTION_VIEW intents
    mCurrentPhotoPath = "file:" + image.getAbsolutePath();
    return image;
}

protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {
        //The image is already stored in the phone, let's open it up from there
        File imgFile = photoFile;
        if(imgFile.exists()){

            Bitmap myBitmap = BitmapFactory.decodeFile(imgFile.getAbsolutePath());

            mImageView.setImageBitmap(myBitmap);

        }

        new UploadFTP<File>().doInBackground(imgFile);
    }
}

这是处理 AsycnTask 的类:

class UploadFTP<File> extends AsyncTask<File, Void, Void> {


@Override
protected Void doInBackground(File... params) {
    File file = params[0];
    try
    {
        SimpleFTP ftp = new SimpleFTP();

        // Connect to an FTP server on port 21.
        ftp.connect("ftp.myurl", 21, "myuser", "mypass");

        // Set binary mode.
        ftp.bin();

        // Change to a new working directory on the FTP server.
        ftp.cwd("www/xxx");

        // Upload files.
        ftp.stor(new java.io.File(String.valueOf(file)));

        ftp.disconnect();
    }
    catch (IOException e)
    {
        e.printStackTrace();
    }
    return null;
 }
}

这里的错误:

FATAL EXCEPTION: main
    Process: com.ignistudios.photosharing, PID: 22214
    java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=1, result=-1, data=null} to activity {com.ignistudios.photosharing/com.ignistudios.photosharing.MainActivity}: android.os.NetworkOnMainThreadException
    at android.app.ActivityThread.deliverResults(ActivityThread.java:3607)
    at android.app.ActivityThread.handleSendResult(ActivityThread.java:3650)
    at android.app.ActivityThread.access$1400(ActivityThread.java:154)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1370)
    at android.os.Handler.dispatchMessage(Handler.java:102)
    at android.os.Looper.loop(Looper.java:135)
    at android.app.ActivityThread.main(ActivityThread.java:5294)
    at java.lang.reflect.Method.invoke(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:372)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:904)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:699)
    Caused by: android.os.NetworkOnMainThreadException
    at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1147)
    at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:110)
    at libcore.io.IoBridge.connectErrno(IoBridge.java:137)
    at libcore.io.IoBridge.connect(IoBridge.java:122)
    at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:183)
    at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:163)
    at java.net.Socket.startupSocket(Socket.java:590)
    at java.net.Socket.tryAllAddresses(Socket.java:128)
    at java.net.Socket.<init>(Socket.java:178)
    at java.net.Socket.<init>(Socket.java:150)
    at org.jibble.simpleftp.SimpleFTP.connect(SimpleFTP.java:68)
    at com.ignistudios.photosharing.UploadFTP.doInBackground(UploadFTP.java:26)
    at com.ignistudios.photosharing.MainActivity.onActivityResult(MainActivity.java:139)
    at android.app.Activity.dispatchActivityResult(Activity.java:6192)
    at android.app.ActivityThread.deliverResults(ActivityThread.java:3603)
    at android.app.ActivityThread.handleSendResult(ActivityThread.java:3650) 
    at android.app.ActivityThread.access$1400(ActivityThread.java:154) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1370) 
    at android.os.Handler.dispatchMessage(Handler.java:102) 
    at android.os.Looper.loop(Looper.java:135) 
    at android.app.ActivityThread.main(ActivityThread.java:5294) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at java.lang.reflect.Method.invoke(Method.java:372) 
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:904) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:699) 

Answer 1

您使用AsyncTask的方式是错误的。在其上调用 execute，它会自动在允许网络操作的不同线程上调用 doInBackground()。

UploadFTP uploadFTP = new UploadFTP();
uploadFTP.execute();