Once

A small Android library to manage one-off operations.

Some things should happen once.

Users should only get the guided tour once.
Release notes should only pop up once every app upgrade.
Your app should only phone home to update content once every hour.

Once provides a simple API to track whether or not your app has already performed an action within a given scope.

Usage

First things first, you'll need to initialise Once on start up. In your Application class's onCreate() override add the follow:

Once.initialise(this);

Now you're ready to go. Say you wanted to navigate to a 'WhatsNew' Activity every time your app is upgraded:

String showWhatsNew = "showWhatsNewTag";

if (!Once.beenDone(Once.THIS_APP_VERSION, showWhatsNew)) {
    startActivity(this, WhatsNewActivity.class);
    Once.markDone(showWhatsNew);
}

Or if you want your app tour to be shown only when a user install, simply check the tag using the THIS_APP_INSTALL scope:

if (!Once.beenDone(Once.THIS_APP_INSTALL, showAppTour)) {
    ...
    Once.markDone(showAppTour);
}

Your app operations can also be rate-limited by time spans. So for example if you only want to phone back to your a maximum of server once per hour, you'd do the following:

if (!Once.beenDone(TimeUnit.HOURS, 1, phonedHome) { ... }

To de-noise your code a bit more you can also static-import the Once methods, so usage looks a bit cleaner

import static jonathanfinerty.once.Once.THIS_APP_INSTALL;
import static jonathanfinerty.once.Once.beenDone;
import static jonathanfinerty.once.Once.markDone;

...
...

if (!beenDone(THIS_APP_VERSION, tagName)) {
    ...
    markDone(showWhatsNew);
}

Installation

Add a library dependency to your app module's build.gradle:

dependencies {
    compile 'com.jonathanfinerty.once:once:0.3.2'
}

You'll need to have jcenter() in your list of repositories

Example

Have a look at the example app in once-example/ for more simple usage.

Contributing

Once was made in '20%' time at Huddle, where its used to help build our Android apps. Pete O'Grady and Paul Simmons also provided invaluable feedback.

Pull requests and github issues are more than welcome and you can get in touch with me directly @jonfinerty.

License

Copyright 2015 Jon Finerty

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

lukezhanin / Once