A simple MVP design

Task: Get data from the network and then display it on the mainactivity listview

I. Loading the framework needed

1. MVP Framework

Compile ' com.hannesdorfmann.mosby:mvp:2.0.1 '

Compile ' com.hannesdorfmann.mosby:viewstate:2.0.1 '

2, retrofit and Rxjava framework

Compile ' io.reactivex:rxandroid:1.2.0 '
Compile ' io.reactivex:rxjava:1.1.5 '
Compile ' com.squareup.okhttp:okhttp:2.5.0 '
Compile ' com.squareup.retrofit:retrofit:2.0.0-beta1 '
Compile ' com.squareup.retrofit:converter-gson:2.0.0-beta1 '
Compile ' com.squareup.retrofit:adapter-rxjava:2.0.0-beta1 '

Second, design sketches

According to the MVP design pattern:

The network request that provides the data is placed in the model package.

The class that will display the screen data into the view package

The logic for processing data and transformations is put into the presents package.

We are here: only need to implement when the data is obtained, the ListView display situation is ready.

Iii. Commencement of work

1, create retrofit network request retrofit use to put under the model this package

 Public classarticleentity{//converting JSON data to entity classes    PrivateString title; PrivateString Detail;  PublicString Getdetail () {returndetail; }     Public voidSetdetail (String detail) { This. Detail =detail; }     PublicString GetTitle () {returntitle; }     Public voidSettitle (String title) { This. title =title; }}

articleentity

 Public Interface Dataapi {// send data request    @GET ("Refreshlayout/api/newdata{pagenumber}.json")    Observableint  pagenumber);}

Dataapi

Finally: Create

 Public classhttpconnection {//address: From the Internet search    Private Static FinalString base_url = "http://7xk9dj.com1.z0.glb.clouddn.com/"; Private Statichttpconnection mhttconnection; PrivateRetrofit Mretrofit; //Create Retrofit    Privatehttpconnection () {Mretrofit=NewRetrofit.builder (). Addcalladapterfactory (Rxjavacalladapterfactory.create ()). Addconver    Terfactory (Gsonconverterfactory.create ()). BASEURL (Base_url). build (); }    //using the singleton mode, plus double lock     Public Static synchronizedhttpconnection Newinstace () {if(Mhttconnection = =NULL){            synchronized(Httpconnection.class) {mhttconnection=Newhttpconnection (); }        }        returnmhttconnection; }    //method of getting data, subscriber as callback interface     Public voidGetData (intpagenum,subscriber Subscriber) {DATAAPI API= Mretrofit.create (Dataapi.class); Observable Observable=api.getarticles (pagenum); Observable.subscribeon (Schedulers.io ()). Observeon (Androidschedulers.mainthread ()). Subscrib    E (subscriber); }}

httpconnection

2. Create View

Analysis: According to our needs, we only need the screen to display the data this one action, so we designed the view is like this

// implementation: Creating interfaces and inheriting interfaces Mvpview  Public Interface extends mvpview{    // get to data, show    void Show (arraylist<articleentity>  Articleitem);}

iarticle

3, Design present class

Again, we just need to show the method.

 Public classArticlepresentextendsMvpbasepresenter<iarticleview> {    Private intMviewpage = 0; Privatehttpconnection mconnection; @Override Public voidAttachview (Iarticleview view) {Super. Attachview (view); Mconnection=Httpconnection.newinstace (); }    //get the data, process it, and pass it to the view's broker     Public voidShow () {//get the view of the previous step        FinalIarticleview view =GetView (); if(View! =NULL) {Subscriber subscriber=NewSubscriber () {@Override Public voidoncompleted () {LOG.D ("Mainactivity", "Done"); } @Override Public voidOnError (Throwable e) {} @Override Public voidonNext (Object o) {//when the data is fetched, the method that calls the viewView.show ((arraylist<articleentity>) o);            }            }; //Get Related DataMconnection.getdata (Mviewpage,subscriber); }    }}

articlepresnt

4. mainactivity Display Data

Basemvpactivity inherited mvpbaseactivity designed a basic encapsulation method, encapsulating some basic methods,

Generics: A generic that is created after the class name is created before the return value of the method

 Public Abstract classBasemvpactivity <vextendsMvpview,textendsMvppresenter<v>>extendsMvpactivity<v,t>{@Overrideprotected voidonCreate (Bundle savedinstancestate) {Super. OnCreate (savedinstancestate);        Initview (savedinstancestate);    Setlistener (); }     Public Abstract voidInitview (Bundle savedinstancestate);  Public Abstract voidSetlistener ();  Public<vtextendsView> VT Getviewbyid (intID) {        return(VT) Findviewbyid (ID); }}

basemvpactivity

 Public classMainactivityextendsBasemvpactivity<iarticleview,articlepresent>Implementsiarticleview{PrivateListView Mlistview; PrivateArticleadapter Marticleadapter; @NonNull @Override Publicarticlepresent Createpresenter () {return Newarticlepresent (); } @Override Public voidInitview (Bundle savedinstancestate) {Mlistview=Getviewbyid (R.id.main_listview); Marticleadapter=NewArticleadapter ( This,NewArraylist<articleentity>());    Mlistview.setadapter (Marticleadapter); } @Override Public voidSetlistener () {} @Override Public voidShow (arraylist<articleentity>Articleitem)    {marticleadapter.addarticles (Articleitem); }}

mainactivity

Step: Inherit basemvpactivity, inherit the Iacrticle interface just now

Design method: Load the class that gets the data into the model, and then specify the interface method for the view display (for example, what interface is displayed when there is no data, what interface is displayed when there is data), and the data in it is not the same.

The logic for processing data and invoking the view method on different data is done in present.

A simple MVP design