I am making an app that stores username and password and automatically login into the wifi. I am storing these data in internal storage. So, to test that whether data has been permanently written, I made a method which will show username and password in toast message. If I am in the app and after saving data, I click on show button, it perfectly shows data. But when I exit app and after reopening the I click on show it force closes.
public class MyActivity extends Activity {
public Button save;
public Button show;
public EditText user;
public EditText pass;
String PRONTO = "PrivateData";
String un;
String pw;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my);
user = (EditText) findViewById(R.id.username);
pass = (EditText) findViewById(R.id.password);
save = (Button) findViewById(R.id.button);
show = (Button) findViewById(R.id.test);
save.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
un = (String) user.getText().toString();
pw = (String) pass.getText().toString();
//Creating file for saving username and passwords
FileOutputStream fos;
try {
fos = openFileOutput(PRONTO, Context.MODE_PRIVATE);
fos.write(un.getBytes());
fos.write(pw.getBytes());
fos.close();
} catch (IOException e) {
throw new RuntimeException(e);
}
}
});
show.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//for testing of storage of data
FileInputStream fis;
try {
fis = openFileInput(PRONTO);
fis.read(un.getBytes());
fis.read(pw.getBytes());
fis.close();
} catch (IOException e) {
throw new RuntimeException(e);
}
//displaying the stored data to user
Toast.makeText(getApplicationContext(), "Username and Password is" + un + " " + pw, Toast.LENGTH_SHORT).show();
}
});
}
}
