java - Android internal files seems to disappear after I restart my application -


i new android , trying save few files in little "play-around" application making learn, files seem persist until application shut down. when run:

file.exists() file.isfile()

or similar methods return false when application restarted.

this method found online save files:

 public void writetofile(string data, string filepath, context context){     file file = new file(context.getfilesdir(), filepath);      if(!file.exists()){         try{             file.createnewfile();         }catch(ioexception e) {             e.printstacktrace();             log.e("exception", "file couldn't created");         }     }      try {         outputstreamwriter outputstreamwriter = new outputstreamwriter(context.openfileoutput(filepath, context.mode_private));         outputstreamwriter.write(data);         outputstreamwriter.close();     }     catch (ioexception e) {         log.e("exception", "file write failed: " + e.tostring());     } }

i have been googling lot trying find solution none of them worked. seems work when application running since can write , read files, @ restart of application, cannot find files. (file.exists() returns false)

i assume attempting write internal storage here? if not , wish access external storage, suggest having through guidance on android.com below.

https://developer.android.com/guide/topics/data/data-storage.html#filesinternal

if is internal storage trying write to, need make sure passing correct context method. example, if running mainactivity class , method contained within class, call along lines of:

writetofile("some data", "afile.txt", mainactivity.this)


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