1.base

BaseActivity

public abstract class BaseActivity
     
      >extends AppCompatActivity {    protected P  mPresenter;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        mPresenter=createPresenter();        mPresenter.attachView((V)this);    }    /**     * activity/view会持有presenter层的引用，presenter会引用model层的引用。model加载的数据极有可能是网络数据，且极     * 有可能是异步子线程加载的数据。加载这样的数据要耗时，一旦用户点击回退推出了当前的view，则view就被释放了，     * 但是当model层加载数据完成后会回掉监听器,他会拿着view的引用去访问一块已经被释放了的view内存。     * 这样是没有必要的，是浪费资源的，导致了内存的泄漏。     */    @Override    protected void onDestroy() {        super.onDestroy();        mPresenter.detachView();    }    public abstract P  createPresenter();}
     

BasePresenter

public abstract class BasePresenter
     
       {    protected WeakReference
      
        mViewRef;//当内存不足时释放内存        public void attachView(V view){        mViewRef=new WeakReference
       
        (view);    }    public void detachView(){        if(mViewRef!=null){            mViewRef.clear();            mViewRef=null;        }    }    protected V getView(){        return mViewRef.get();    }}
       
      
     

2.Activity

UserActivity

public class UserActivity extends BaseActivity
     
       implements UserView{    private ListView listview;    private UserAdapter mAdapter;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        listview= (ListView) findViewById(R.id.list_view);        //入口        mPresenter.fetch();    }    @Override    public UserPresenter createPresenter() {        return new UserPresenter();    }    @Override    public void showLoading() {        Toast.makeText(getApplicationContext(),"正在加载...",Toast.LENGTH_LONG).show();    }    @Override    public void showDatas(List
      
        datas) {        mAdapter=new UserAdapter(getApplicationContext(), datas);        listview.setAdapter(mAdapter);    }}
      
     

3.view

UserView

public interface  UserView {    void showLoading();    void showDatas(List
     
        datas);}
     

4.presenter　　

UserPresenter

public class UserPresenter extends BasePresenter
     
       {    UserModel userModel=new UserModelImpl();    public void fetch(){        getView().showLoading();        if(userModel!=null){            userModel.loadDatas(new UserModel.DataOnLoadingListener() {                @Override                public void onComplete(List
      
        datas) {                    getView().showDatas(datas);                }            });        }    }}
      
     

 

5.model

UserModel

public interface  UserModel {    void loadDatas(DataOnLoadingListener listener);    interface DataOnLoadingListener{        void onComplete(List
     
       datas);    }}
     

UserModelImpl

public class UserModelImpl implements  UserModel {    @Override    public void loadDatas(DataOnLoadingListener listener) {        List
     
       datas= DataUtil.getInstance().getData();        listener.onComplete(datas);    }}
     

6.其他的无关的

UserAdapter

public class UserAdapter extends BaseAdapter {    private Context context;    private List
     
       datas;    public UserAdapter(Context context,List
      
       datas){        this.context=context;        this.datas=datas;    }    @Override    public int getCount() {        return datas.size();    }    @Override    public Object getItem(int position) {        return datas.get(position);    }    @Override    public long getItemId(int position) {        return position;    }    @Override    public View getView(int position, View convertView, ViewGroup parent) {        if(convertView==null){            convertView=View.inflate(context, R.layout.item, null);        }        ViewHolder holder=ViewHolder.getHolder(convertView);        holder.tv.setText(datas.get(position).getName());        return convertView;    }    static class ViewHolder{        TextView tv;        public ViewHolder(View convertView){            tv=(TextView) convertView.findViewById(R.id.textView);        }        public static ViewHolder getHolder(View convertView){            ViewHolder holder=(ViewHolder) convertView.getTag();            if(holder==null){                holder = new ViewHolder(convertView);                convertView.setTag(holder);            }            return holder;        }    }}
      
     

　　

User

public class User {    private String name;    public User(String name) {        this.name = name;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }}

　　

DataUtil

public class DataUtil {    private static DataUtil dataUtil=null;    public static DataUtil getInstance(){        if(dataUtil==null){            dataUtil=new DataUtil();        }        return dataUtil;    }    public List
     
       getData(){        List
      
        datas = new ArrayList<>();        for (int i = 0; i < 20; i++) {            User user = new User("" + i);            datas.add(user);        }        return datas;    }}