The diycode open source project instance builds fragments for pull-up loading and pull-down refresh

The following explains the implementation of the fragment of pull-up loading and pull-down refresh through three knowledge points, and introduces the usage of each knowledge point.

1. Effect preview

1.1. This home page is a fragment, and this article describes the construction method of this fragment.

The pull-down will have a rotating refresh circle, and the pull-up will refresh the data.

1.2. Overall structure

First, the bottom layer is basefragment

Then refreshrecyclerfragment inherits basefragment

Then simplerefreshrecyclefragment inherits the refreshrecyclerfragment

So if you want to apply classes, you just need to inherit simplerefreshrecyclefragment.

2. The most basic basefragment

2.1. Let's first look at the member variables

Viewholder as view manager

Config is used as configuration status information

Diycode is an online server of the project

Datacache is a buffer

2.2.oncreate function to complete initialization

Config is to get the singleton.

Diycode is also a singleton. 　

Datacache is a new class.

2.3. Define the abstract function to obtain the layout ID

This function will be implemented in the successor.

2.4. Obtain viewholder in this class

2.5. Implement oncreateview

The newly created viewholder actually uses a getlayouteid () method, which calls the abstract function of this class.

Then a view is returned.

2.6. Implement the abstract function initviews

2.7. Copying onactivitycreated

Implements the indirect call to abstract functions.

2.8. Prompt function toast

2.9. Life cycle of a fragment

Therefore, the execution order here is:

onCreate==>onCreateView==>onActivityCreate

Oncreate function: initialize configuration and create diycode singleton and data buffer.

Oncreateview function: get viewholder.

Onactivitycreate function: implement an abstract function initviews, which is used to implement the base class.

3. Fragment with pull-down refresh and pull-up loading