Exercise_6_1_New_Datasource.md

Objectives:

• Learn how to make HTTP request, get response, parse the response and display the data in UI.

Should know what are supported methods for a HTTP request, what is RESTful API, json, xml...

• Network operation should be run on another thread out of main thread to prevent UI blocking

Use your knowledge about threads and processes to do this.

Requirements:

• Level up your app from Exercise 2.1
• Use reddit API to get reddit posts instead of read from local json file.
• The documentation for reddit API is located at: https://www.reddit.com/dev/api
• The API we will use is: https://www.reddit.com/r/androiddev/new.json

Please notice how to get more posts by using after parameter.

• Implements another class called NetworkBasedFeedDataStore to make HTTP request and get reddit posts. (The skeleton code for this class can be found here: NetworkBasedFeedDataStore)
• There will be a delay while waiting for the request to be made, please use SwipeRefreshLayout to show a loading indicator and provides pull to refresh action.

Pull to refresh is an action when user pulls down on the list, the data will be refreshed with the latest one.

• Loading indicator should be hidden after data has been pulled and displayed on UI.
• Users always want to read a lot, so developer would provides a way to load more posts for them.
  • When user scrolls to the end of the list, call the API to get more posts.
  • Show a loading indicator similar to the screenshot below while loading and replace it by new data when complete.

• If the network call for the first page has failed (by multiple reasons): please show a UI like this:

• When user pull to refresh, what is currently displayed on the UI will be discarded and user will see the first page of posts again.

References:

• Synchronous vs Asynchronous: http://www.javatpoint.com/understanding-synchronous-vs-asynchronous
• Basic about HTTP: http://www.tutorialspoint.com/http/index.htm
• How to connect and make a HTTP request: http://developer.android.com/training/basics/network-ops/connecting.html
• How to use Volley: http://developer.android.com/training/volley/index.html
• Some other network libraries:
  • OkHttp: http://square.github.io/okhttp/
  • Retrofit 1.x: https://guides.codepath.com/android/Consuming-APIs-with-Retrofit
  • Ion: https://github.com/koush/ion
• How to use SwipeRefreshLayout: http://antonioleiva.com/swiperefreshlayout/