implementation 'com.google.android.gms:play-services-drive:17.0.0'

// 在Activity或Fragment中
private static final int REQUEST_CODE_OPEN = 1;

private void openFilePicker() {
    Intent pickerIntent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
    pickerIntent.addCategory(Intent.CATEGORY_OPENABLE);
    pickerIntent.setType("*/*"); // 所有文件类型，也可以指定如"image/*"
    
    // 可选：限制为Google Drive文件
    pickerIntent.putExtra(Intent.EXTRA_LOCAL_ONLY, false);
    
    startActivityForResult(pickerIntent, REQUEST_CODE_OPEN);
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == REQUEST_CODE_OPEN && resultCode == RESULT_OK) {
        Uri uri = data.getData();
        // 处理选中的文件URI
        handleSelectedFile(uri);
    }
}

private void handleSelectedFile(Uri uri) {
    try {
        // 获取文件输入流
        InputStream inputStream = getContentResolver().openInputStream(uri);
        // 读取文件内容或执行其他操作
        // ...
    } catch (IOException e) {
        e.printStackTrace();
    }
}

private static final int REQUEST_CODE_CREATE = 2;

private void createFilePicker() {
    Intent createIntent = new Intent(Intent.ACTION_CREATE_DOCUMENT);
    createIntent.addCategory(Intent.CATEGORY_OPENABLE);
    createIntent.setType("text/plain"); // 文件类型
    createIntent.putExtra(Intent.EXTRA_TITLE, "newfile.txt"); // 默认文件名
    
    startActivityForResult(createIntent, REQUEST_CODE_CREATE);
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == REQUEST_CODE_CREATE && resultCode == RESULT_OK) {
        Uri uri = data.getData();
        // 写入新文件内容
        writeFileContent(uri);
    }
}

private void writeFileContent(Uri uri) {
    try {
        OutputStream outputStream = getContentResolver().openOutputStream(uri);
        String content = "这是新文件的内容";
        outputStream.write(content.getBytes());
        outputStream.close();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

// 在onActivityResult中
if (uri != null) {
    final int takeFlags = data.getFlags() 
            & (Intent.FLAG_GRANT_READ_URI_PERMISSION 
            | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
    getContentResolver().takePersistableUriPermission(uri, takeFlags);
}

private void handleLargeFile(Uri uri) {
    new AsyncTask<Uri, Void, Void>() {
        @Override
        protected Void doInBackground(Uri... uris) {
            try {
                InputStream inputStream = getContentResolver().openInputStream(uris[0]);
                BufferedInputStream bis = new BufferedInputStream(inputStream);
                byte[] buffer = new byte[8192]; // 8KB缓冲区
                int bytesRead;
                while ((bytesRead = bis.read(buffer)) != -1) {
                    // 处理每一块数据
                }
                bis.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }
    }.execute(uri);
}

// 只选择图片
pickerIntent.setType("image/*");
// 或多种类型
pickerIntent.setType("image/*|application/pdf");