android - 将 Firebase 存储下载 URL 推送到 Firebase 云 Firestore

Question

如何将 Firebase 存储文件的下载 URL 推送到 Firestore 云端？我有一个项目可以将PDF文件上传到Firestore存储，但是我无法将上传文件的下载地址推送到Firestore云端。

我需要捕获每个文件的上传 URL 并将其发送到 firestore 中的文档以便能够下载它。我正在上传和下载 PDF 文件。

这是我的代码:

public class pdfUploader extends AppCompatActivity {
    private StorageReference mStorageRef;
    Button upload;
    Button select;
    int CODE=215;
    private CollectionReference dbFirestore;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_pdf_uploader);
        mStorageRef = FirebaseStorage.getInstance().getReference();
        upload = findViewById(R.id.upload);
        select = findViewById(R.id.choose);
        select.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                selectFile();
            }
        });
    }

    public void selectFile () {
        Intent i = new Intent(Intent.ACTION_GET_CONTENT);
        i.setType("*/*");
        startActivityForResult(Intent.createChooser(i,"Select a file"), CODE);
    }

    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        String filePath = data.getDataString();
        Uri SelectedFileLocation=Uri.parse(filePath);
        UploadFile(SelectedFileLocation);
        super.onActivityResult(requestCode, resultCode, data);
    }

    public  void UploadFile( Uri file) {
        Toast.makeText(this, "Please wait.. the file is uploading!", Toast.LENGTH_SHORT).show();
        //Uri file = Uri.fromFile(new File("path/to/images/rivers.jpg"));
        StorageReference riversRef = mStorageRef.child(Objects.requireNonNull(file.getLastPathSegment()));
        riversRef.putFile(file)
            .addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() {
                @Override
                public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) {
                    Toast.makeText(pdfUploader.this, "Upload Success", Toast.LENGTH_SHORT).show();
                }
            }).addOnFailureListener(new OnFailureListener() {
                @Override
                public void onFailure(@NonNull Exception exception) {
                    Toast.makeText(pdfUploader.this, "Upload Failed", Toast.LENGTH_SHORT).show();

                }
            });
    }
}

Answer 1

在顶部分配这个变量

FirebaseFirestore db;

//In oncreateView we have to assign now db so.
db = FirebaseFirestore.getInstance();

获取文件uri的代码:

riversRef.putFile(File).addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() {
    @Override
    public void onSuccess(UploadTask.TaskSnapshot taskSnapshot)
    {
        riversRef.getDownloadUrl().addOnSuccessListener(new OnSuccessListener<Uri>() {
                @Override
                public void onSuccess(Uri uri) {
                    Uri downloadUrl = uri;
                    Toast.makeText(MtActivity.this, "Upload Done", Toast.LENGTH_LONG).show();   
                    //After upload Complete we have to store the Data to firestore.
                    Map<String, Object> file = new HashMap<>();
                    file.put("url", downloadUrl.toString()); // We are using it as String because our data type in Firestore will be String
                    db.collection("/*Put you're collection name*/").document("/*And Document name Here*/")
                            .set(file)
                            .addOnSuccessListener(new OnSuccessListener<Void>() {
                                @Override
                                public void onSuccess(Void aVoid) {
                                    Log.d(TAG, "DocumentSnapshot successfully written!");
                                }
                            })
                            .addOnFailureListener(new OnFailureListener() {
                                @Override
                                public void onFailure(@NonNull Exception e) {
                                    Log.w(TAG, "Error writing document", e);
                                }
                            });
                }
    }
});

如果下载 url 过期，则有更好的方法将您的图像文件存储在您的存储和 firestore 中

代码:

riversRef.putFile(file)
                .addOnSuccessListener(new OnSuccessListener<UploadTask.TaskSnapshot>() {
                    @Override
                    public void onSuccess(UploadTask.TaskSnapshot taskSnapshot) {
                        String path = //Put path of storage it will be something like [images/filename.jpg(Put your extension of file)] this path from firebase storage
                        Map<String, Object> file = new HashMap<>();
                        file.put("url", path); // We are using it as String because our data type in Firestore will be String
                        db.collection("/*Put you're collection name*/").document("/*And Document id Here*/")
                                .set(file)
                                .addOnSuccessListener(new OnSuccessListener<Void>() {
                                    @Override
                                    public void onSuccess(Void aVoid) {
                                        Log.d(TAG, "DocumentSnapshot successfully written!");
                                    }
                                })
                                .addOnFailureListener(new OnFailureListener() {
                                    @Override
                                    public void onFailure(@NonNull Exception e) {
                                        Log.w(TAG, "Error writing document", e);
                                    }
                                });
                    }
                })
                .addOnFailureListener(new OnFailureListener() {
                    @Override
                    public void onFailure(@NonNull Exception exception) {
                        Toast.makeText(pdfUploader.this, "Upload Failed", Toast.LENGTH_SHORT).show();

                    }
                });

当您处理图像并阅读此 docs 时，上面的代码将会有用且更好更多详情