在Android中存储数据

Question

I am currently working on my first app and I have decided to do it on android. I have the main activity layout the way I wish and the Time/Date displaying dynamically.

What I am needing help with is I need the app to save the date and time whenever a button is pressed. This data will need to be available for 1 week (7 Days) and then it may be overwritten the following week to save space on the device.

Ideally there would be two button presses a day, one to clock in/clock out (App to keep track of my hours at work and calculate pay). What is the best way to go about this? Can you guys point me in the right direction to storing this data?

I thought about using Parse but then an online connection would be needed, correct? Is there anyway to do this locally and then maybe I can implement online storage later?

Answer 1

If the data you want to save isn't very complex I'd use SharedPreferences. Here's an example:

To write data:

SharedPreferences sharedPref = getSharedPreferences("com.example.myapp.PREFERENCE_FILE_KEY",
    Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putLong("clockIn", clockIn.getTime());
editor.commit();

To read data:

SharedPreferences sharedPref = getSharedPreferences("com.example.myapp.PREFERENCE_FILE_KEY",
    Context.MODE_PRIVATE);
Date clockIn = new Date(getResources().getLong("clockIn"));

Take a look at this for more info: https://developer.android.com/training/basics/data-storage/shared-preferences.html

Answer 2

The simplest way would be to use SharedPreferences, but a more comprehensive, dynamic storage would be using Sqlite.

Shared Preferences

SharedPreferences prefs = getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE);

prefs.putLong(FIRST_TIME,nix timestamp).commit();

prefs.putLong(SECOND_TIME, nix timestamp).commit();

And retrieve the same way:

long firstTime = prefs.getLong(FIRST_TIME);

long secondTime = prefs.getLong(SECOND_TIME);

Answer 3

最好的方法是存储在本地db（Sqlite）中。