为什么无法在 firebase 存储上上传图片?

why Unable to upload a picture on firebase storage?

这段代码有错误:

String download_url=task.getResult.getStorage.getDownloadUrl.toString);

当我 运行 程序时,我从图库中选择一张图片 post 它,我收到一条消息:

User is not authenticated, please authenticate using Firebase Authentication and try again

final StorageReference newPhoto=mPhotosStrorage.child(imageUri.getLastPathSegment());
newPhoto.putFile(imageUri).addOnCompleteListener(new OnCompleteListener<UploadTask.TaskSnapshot>() {
    @Override
    public void onComplete(@NonNull Task<UploadTask.TaskSnapshot> task) {

        if (task.isSuccessful())
        {
            final String myKey=mPhotosDatabase.push().getKey();

 //this error       String download_url=task.getResult().getDownloadUrl().toString();

            String datem=getDateTime();              

            DatabaseReference newDatabase=mPhotosDatabase.child(myKey);

            newDatabase.child("postid").setValue(myKey);
            newDatabase.child("postedby").setValue(userId);
            newDatabase.child("postedon").setValue(datem);
            newDatabase.child("postdetails").setValue(post);
            newDatabase.child("postlikes");
            newDatabase.child("postviews");
            newDatabase.child("postcomments");

            newDatabase.child("postimage").setValue(download_url).addOnCompleteListener(new OnCompleteListener<Void>() {
                @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
                @Override
                public void onComplete(@NonNull Task<Void> task) {

                    if (task.isSuccessful())
                    {
                        pb.setVisibility(View.GONE);
                        Pair[] pairs=new Pair[1];
                        pairs[0]=new Pair<View,String>(homeLayout,"etTransition");

                        ActivityOptions options=ActivityOptions.makeSceneTransitionAnimation(PostActivity.this,pairs);

                        startActivity(new Intent(PostActivity.this,HomeActivity.class),options.toBundle());

                    }
                }
            });
        }else {
            Toast.makeText(PostActivity.this, "Error:"+task.getException().getMessage(), Toast.LENGTH_SHORT).show();
        }
    }
});

请帮我解决并重写代码

根据您最后的评论,问题出在以下代码行:

String download_url=task.getResult().getDownloadUrl().toString();

请注意,现在这不是您下载 URL 的方式。将该 Task 对象转换为 String 根本没有帮助。要解决此问题,请使用以下代码行:

storageRef.getDownloadUrl().addOnSuccessListener(new OnSuccessListener<Uri>() {
    @Override
    public void onSuccess(Uri uri) {
        String url = uri.toString();
        //Do what you need to do with the URL
    }
});

除此之外,请始终确保对用户进行身份验证,因为只有在用户未通过身份验证且规则设置为拒绝操作时才会发生该错误。