Saving Data on Android

WRITE_EXTERNAL_STORAGE
 permission inside the 

 element in 
AndroidManifest.xml
.
Wri/ng the notes to external storage
Now that the correct permissions are in place, it’s time to write the file to the 
external storage. Open 
ExternalFileRepository.kt
 and add the following code to 
addNote
:
Saving Data on Android
Chapter 1: Using Files
raywenderlich.com
29

---

// 1
 
if
 (isExternalStorageWritable()) { 
  
// 2
 
  FileOutputStream(noteFile(note.fileName)).use { output -> 
    output.write(note.noteText.toByteArray()) 
  } 
}
Here’s how it works:
1. Check to see if the external storage is available.
2. Open a 
FileOutputStream
 with 
use
.
3. Write 
note.noteText
 to the file.
Next, in 
MainActivity.kt
, change the instance of the 
NoteRepository
 you’re 
initializing to the following:
private
 val repo: 
NoteRepository
 by 
lazy
 
{ 
ExternalFileRepository
(this) }
Finally, run the program to write a file to the external storage. To view the file using 
the Device File Explorer, look in 
sdcard/data
, within the app’s package name folder.
You’ll implement the app’s read function in the next step.