等待所有上传完成，然后再执行下一个功能Firebase Storage

Question

我正在使用for循环从arraylist上传一系列文件

confirmButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
getFilePaths();
for (int i = 0; i < mFileURIs.size(); i++) {
    Uri uri = mFileURIs.get(i);
    uploadPDF(uri, mFileNAMES.get(i));
}
initiatePayment();

所有文件上传后如何执行其他功能？由于其他函数具有在文件上传时填充的变量，因此mFileURLs会在文件上传后存储文件的URL。

        private void uploadPDF(Uri uri, String pdfName) {

        mFileURLS = new ArrayList<>();

        final ProgressDialog progressDialog = new ProgressDialog(this);
        progressDialog.setTitle("Uploading...");
        progressDialog.show();

        StorageReference reference = storage.getReference();

        StorageReference pdfFolder = reference.child(user.getUid());

        StorageReference pdfRef = pdfFolder.child(pdfName);
        pdfRef.putFile(uri).addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() {
            @Override
            public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) {
                progressDialog.dismiss();
                pdfRef.getDownloadUrl().addOnSuccessListener(new OnSuccessListener<Uri>() {
                    @Override
                    public void onSuccess(Uri uri) {
                        String url = uri.toString();
                        Log.e("DD", "onSuccess: " + url);
                        mFileURLS.add(url);
                        counter++;
                    }
                }).addOnFailureListener(new OnFailureListener() {
                    @Override
                    public void onFailure(@NonNull Exception exception) {
                        // Handle any errors
                    }
                });
                Toast.makeText(getApplicationContext(), "UPLOADED SUCCESSFULLY", Toast.LENGTH_SHORT).show();
            }
        }).addOnFailureListener(new OnFailureListener() {
            @Override
            public void onFailure(@NonNull Exception e) {
                Log.e("FirebaseActivity", "On Failure: " + e.getMessage());
                Toast.makeText(getApplicationContext(), "FAILED TO UPLOAD", Toast.LENGTH_SHORT).show();
            }
        }).addOnProgressListener(new OnProgressListener<UploadTask.TaskSnapshot>() {
            @Override
            public void onProgress(UploadTask.TaskSnapshot taskSnapshot) {
                double progress = (100.0 * taskSnapshot.getBytesTransferred() / taskSnapshot
                        .getTotalByteCount());
                progressDialog.setMessage("Uploaded " + (int) progress + "%");
            }
        });
    }

类似于此问题-Firebase Storage - Wait till all upload tasks are completed before executing function

但是在android中。谢谢！