getDownloadUrl function doesn't return the right url

Question

I am uploading a pdf to Firebase Storage and want to get its download url. I am using the following code:

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    switch (requestCode) {
        case 1212:
            if (resultCode == RESULT_OK) {
                String FilePath = data.getDataString();
                t.setText(FilePath);
                Uri pdfuri = data.getData();
                final StorageReference mp = mpdf.child("pdf").child(random()+".pdf");
                mp.putFile(pdfuri).addOnCompleteListener(new OnCompleteListener<UploadTask.TaskSnapshot>() {
                    @Override
                    public void onComplete(@NonNull Task<UploadTask.TaskSnapshot> task) {
                        if(task.isSuccessful())
                        {
                            String download_url = task.getResult().getMetadata().getReference().getDownloadUrl().toString();
                            String parent = getIntent().getStringExtra("type").toString();
                            String ch = getIntent().getStringExtra("value").toString();
                            GeologicDatabase.modifySingle(parent,ch,download_url);
                            Toast.makeText(modifypdf.this,download_url , Toast.LENGTH_SHORT).show();
                            finish();
                        }
                        else {
                            Toast.makeText(modifypdf.this,"Faild" , Toast.LENGTH_SHORT).show();
                        }
                    }
                });
            }
            break;
    }
    super.onActivityResult(requestCode, resultCode, data);
}

the result of the line

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

is "com.google.android.gms.tasks.zzu@7f93358" not the right url

---

the solution of the problem is to use upload task and in its in Complete Listener you write your code get the result of the task as a Uri and cast it into String

final String name = random() + ".pdf";
                dp = mpdf.child("pdf").child(name);
                UploadTask uploadTask = dp.putFile(pdfuri);
                Task<Uri> urlTask = uploadTask.continueWithTask(new Continuation<UploadTask.TaskSnapshot, Task<Uri>>() {
                    @Override
                    public Task<Uri> then(@NonNull Task<UploadTask.TaskSnapshot> task) throws Exception {
                        if (!task.isSuccessful()) {
                            throw task.getException();
                        }

                        // Continue with the task to get the download URL
                        return dp.getDownloadUrl();
                    }
                }).addOnCompleteListener(new OnCompleteListener<Uri>() {
                    @Override
                    public void onComplete(@NonNull Task<Uri> task) {
                        if (task.isSuccessful()) {
                            tt = title.getText().toString();
                            Uri downloadUri = task.getResult();
                            String download_url = downloadUri.toString();
                            String parent = getIntent().getStringExtra("type").toString();
                            String ch = getIntent().getStringExtra("value").toString();
                            GeologicDatabase.updateChild(parent, ch, "url",download_url,tt);
                            GeologicDatabase.updateChild(parent,ch,"name",name,tt);
                            Toast.makeText(addpdf.this, download_url, Toast.LENGTH_SHORT).show();
                            finish();
                        } else {
                            // Handle failures
                            // ...
                        }
                    }
                });

Answer 1

getDownloadUrl() doesn't return a URL. As you can see from the javadoc, it returns a Task that yields the URL. You'll have to wait on this Task to complete in order to get the final URL.

Answer 2

//尝试这个

ret=output_excel.rename(columns={"Home":str(self.hhid)+" Home","HH1 distance [km]":str(self.hhid)+" Distance Car1 [km]", "Energy [kWh]":str(self.hhid)+" Energy Car1 [kWh]"})
return ret