Ionic 4 + capacitor. How to open a file?

Question

Android

I'm trying to open a file that is in the system, which was successfully downloadedFilesystem.writeFile

viewFile() {
      try {
        Filesystem.readFile({
          path: "enedis.pdf",
          directory: FilesystemDirectory.Documents
        });
      } catch (e) {
        console.error("Read file error", e);
      }
    },

But nothing happens.
Here is what the console says

Answer 1

What should happen? You have loaded the file into memory, but do nothing else with it.