Question

编辑：关于这个问题的讨论已经转移到另一个问题：Image capture with camera & upload to Firebase (Uri in onActivityResult() is null)请检查出来！我做了一些操作（遵循android文档）但仍然遇到同样的问题。

所以我在这里尝试使用相机捕获图像并将其上传到Firebase上的存储数据库。我有以下按钮来完成这项工作：

b_capture.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
            startActivityForResult(intent, CAMERA_REQUEST_CODE);
        }
    });

以及上传的以下代码：

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    if(requestCode == CAMERA_REQUEST_CODE && resultCode == RESULT_OK){
        progressDialog.setMessage("Uploading...");
        progressDialog.show();
        Uri uri = data.getData();
        StorageReference filepath = storage.child("Photos").child(uri.getLastPathSegment());
        filepath.putFile(uri).addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() {
            @Override
            public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) {
                Toast.makeText(MainActivity.this, "Upload Successful!", Toast.LENGTH_SHORT).show();
                progressDialog.dismiss();
            }
        }).addOnFailureListener(new OnFailureListener() {
            @Override
            public void onFailure(@NonNull Exception e) {
                Toast.makeText(MainActivity.this, "Upload Failed!", Toast.LENGTH_SHORT).show();
            }
        });
      }
    }

在应用程序中我可以拍照，但在我确认照片拍摄APP CRASHES后我收到以下错误：

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.net.Uri.getLastPathSegment()' on a null object reference

所以，我明白了＆＃34; Uri＆＃34;它里面没有任何东西，但我对可以做的事感到困惑。需要帮助。

是的，我已经检查了所有权限，Firebase连接，Gradle同步等。

Answer 1

您需要重新阅读the documentation并按照示例创建文件并将其Uri存储在图像捕获意图中。这是您需要添加的文档中的代码：

String mCurrentPhotoPath;

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 = getExternalFilesDir(Environment.DIRECTORY_PICTURES);
    File image = File.createTempFile(
        imageFileName,  /* prefix */
        ".jpg",         /* suffix */
        storageDir      /* directory */
    );

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

private void dispatchTakePictureIntent() {
    Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    // Ensure that there's a camera activity to handle the intent
    if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
        // Create the File where the photo should go
        File photoFile = null;
        try {
            photoFile = createImageFile();
        } catch (IOException ex) {
            // Error occurred while creating the File
            ...
        }
        // Continue only if the File was successfully created
        if (photoFile != null) {
            Uri photoURI = FileProvider.getUriForFile(this,
                                                  "com.example.android.fileprovider",
                                                  photoFile);
            takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI);
            startActivityForResult(takePictureIntent, REQUEST_TAKE_PHOTO);
        }
    }
}


b_capture.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            dispatchTakePictureIntent()

            //Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
            //startActivityForResult(intent, CAMERA_REQUEST_CODE);
        }
    });

Answer 2

在以下讨论中解决了问题：Image capture with camera & upload to Firebase (Uri in onActivityResult() is null)感谢所有参与的人！

将图像（ACTION_IMAGE_CAPTURE）上传到Firebase存储

2 个答案: