mvp的全称为Model-View-Presenter,Model提供数据,View负责显示,Controller/Presenter负责逻辑的处理。MVP与MVC有着一个重大的区别:在MVP中View并不直接使用Model,它们之间的通信是通过Presenter
(MVC中的Controller)来进行的,所有的交互都发生在Presenter内部,而在MVC中View会直接从Model中读取数据而不是通过 Controller。
项目中大部分是面对接口编程,通过P层可以预先将所有需要的接口功能写出来,进而进行实现,大大提高了项目高内聚,低耦合。适合于团队开发项目。
今天我们是用MVP的设计框架模板来实现一个ListView的上拉刷新下拉加载更多的功能。
项目结构如下图;
1、首先我们ListViewPresenters.java类,他的作用是,控制M业务逻辑层,去获取我们想要的数据,然后通知V层去更新他们对应的UI。由于我们的需求明确,就是实现Listview的上拉刷新,下拉加载更多,初始化控件,设置上拉下拉刷新监听。因此我们可以先把功能接口都写好,让ListViewPresenters去实现其功能即可。
package com.android.presenters; import java.util.ArrayList; import android.support.v4.app.FragmentActivity; import android.view.View; import com.android.handlers.ListViewHandle; import com.android.services.ListViewService; import com.android.services.si.IListViewService; import com.android.view.ListViewFerris; import com.android.view.vi.IListViewFerris; import com.android.widget.listview.FerrisListView.OnStartListener; public class ListViewPresenters { private IListViewFerris iListViewFerris; private IListViewService iListViewService; private FragmentActivity mActivity; private View view; private int index = 1; public ListViewPresenters(FragmentActivity mActivity2, View view2) { // TODO Auto-generated constructor stub this.mActivity = mActivity2; this.view = view2; this.iListViewFerris = new ListViewFerris(mActivity, view); this.iListViewService = new ListViewService(); } /* * 初始化View层里的控件 */ public void onFindView() { iListViewFerris.onFindView(); } /* * 上啦刷新方法 */ public void listViewRefresh(int index) { //post请求数据,获取数据,并且通过handler接口来通知View更新UI iListViewService.sendPost(index, new ListViewHandle() { @Override public void getData(ArrayList<String> msgs) { // TODO Auto-generated method stub //通过handler接口来通知UI去更新数据 iListViewFerris.refresh(msgs); } }); } /* * 下拉加载更多方法 */ public void listViewLoadMore(int index) { //post请求数据,获取数据,并且通过handler接口来通知View更新UI iListViewService.sendPost(index, new ListViewHandle() { @Override public void getData(ArrayList<String> msgs) { // TODO Auto-generated method stub //通过handler接口来通知UI去更新数据 if (msgs == null) { iListViewFerris.showLoadingError();//获取数据失败显示通知 iListViewFerris.loadMore(msgs);//停止加载更多 } else { iListViewFerris.loadMore(msgs);//停止加载更多 } } }); } /* * 为Listview设置上拉下拉刷新监听 */ public void setRefreshOrLoadMoreListem() { // TODO Auto-generated method stub iListViewFerris.setRefreshOrLoadMoreListem(new Refresh(), new Loadmore()); } /* * 为Listview第一次,自动下拉刷新 */ public void firstload() { // TODO Auto-generated method stub iListViewFerris.firstLoad(); } /* * 上拉刷新监听 */ public class Refresh implements OnStartListener { @Override public void onStart() { // TODO Auto-generated method stub index = 1; listViewRefresh(index); } } /* * 加载更多监听 */ public class Loadmore implements OnStartListener { @Override public void onStart() { // TODO Auto-generated method stub listViewLoadMore(++index); } } }
2、接着我们来看下UI层,我们需要更新哪些数据,需要为哪个UI去具体更新哪些东西。
package com.android.view.vi; import java.util.ArrayList; import com.android.widget.listview.FerrisListView.OnStartListener; public interface IListViewFerris { public void onFindView();//初始化控件 public void showLoadingError();//显示加载错误 public void showLoadingSuccess();//显示加成功 public void setNotifyListView();//刷新Listview public void refresh(ArrayList<String> msgs);//上拉刷新 public void loadMore(ArrayList<String> msgs);//下拉加载更多 public void setRefreshOrLoadMoreListem(OnStartListener refresh, OnStartListener loadmore);//设置上拉下拉刷新监听 public void firstLoad();//首次自动上拉刷新 }
具体UI层实现的具体方法,主要是 上拉刷新,下拉加载更多,显示错误成功状态,以及初始化控件等方法。
package com.android.view; import java.util.ArrayList; import android.support.v4.app.FragmentActivity; import android.view.View; import com.android.adapter.ListViewAdapter; import com.android.futilssimple.R; import com.android.utils.ToastUtils; import com.android.view.vi.IListViewFerris; import com.android.widget.listview.FerrisListView; import com.android.widget.listview.FerrisListView.OnStartListener; import com.android.widget.listview.SimpleFooter; import com.android.widget.listview.SimpleHeader; public class ListViewFerris implements IListViewFerris{ private FragmentActivity mActivity; private View view; private FerrisListView listView; private ListViewAdapter adapter; public ListViewFerris(FragmentActivity mActivity,View view) { // TODO Auto-generated constructor stub this.mActivity=mActivity; this.view=view; } //初始化view @Override public void onFindView() { // TODO Auto-generated method stub if(mActivity==null||view==null){ return; } listView = (FerrisListView)view.findViewById(R.id.zListView); adapter=new ListViewAdapter(mActivity); // 设置默认偏移量,主要用于实现透明标题栏功能。(可选) float density = mActivity.getResources().getDisplayMetrics().density; listView.setFirstTopOffset((int) (50 * density)); // 设置下拉刷新的样式(可选,但如果没有Header则无法下拉刷新) SimpleHeader header = new SimpleHeader(mActivity); header.setTextColor(0xff0066aa); header.setCircleColor(0xff33bbee); listView.setHeadable(header); // 设置加载更多的样式(可选) SimpleFooter footer = new SimpleFooter(mActivity); footer.setCircleColor(0xff33bbee); listView.setFootable(footer); } //显示加载失败 @Override public void showLoadingError() { // TODO Auto-generated method stub ToastUtils.showToast(mActivity, "加载失败"); } //显示加载成功 @Override public void showLoadingSuccess() { // TODO Auto-generated method stub ToastUtils.showToast(mActivity, "加载成功"); } //刷新数据 @Override public void setNotifyListView() { // TODO Auto-generated method stub if(adapter!=null){ adapter.notifyDataSetChanged(); } } //填充刷新数据 @Override public void refresh(ArrayList<String> msgs) { // TODO Auto-generated method stub if(msgs!=null&&msgs.size()>0){ if(listView.getAdapter()==null){ listView.setAdapter(adapter); adapter.setRefresh(msgs); }else{ adapter.setRefresh(msgs); } listView.setRefreshSuccess("加载成功"); // 通知加载成功 listView.startLoadMore(); // 开启LoadingMore功能 }else{ listView.setRefreshFail("加载失败"); } } //填充加载更多数据 @Override public void loadMore(ArrayList<String> msgs) { // TODO Auto-generated method stub if(msgs!=null&&msgs.size()>0){ if(listView.getAdapter()==null){ listView.setAdapter(adapter); adapter.setData(msgs); }else{ adapter.setData(msgs); } listView.setLoadMoreSuccess(); }else{ listView.stopLoadMore(); } } //为Listview设置首次自动上拉刷新 @Override public void firstLoad(){ listView.refresh(); // 主动下拉刷新 } //为Listview设置上拉以及下拉刷新 @Override public void setRefreshOrLoadMoreListem(OnStartListener refresh, OnStartListener loadmore) { // TODO Auto-generated method stub listView.setOnRefreshStartListener(refresh); listView.setOnLoadMoreStartListener(loadmore); } }
3、我们来看下业务逻辑层,主要是通过模拟POST在后台请求数据,然后将获取的数据,返回给P层,由P层去将数据交予V层来更新UI界面。
package com.android.services.si; import com.android.handlers.ListViewHandle; public interface IListViewService { //发送post请求 public void sendPost(int index,ListViewHandle handle); }
业务逻辑才具体实现的功能如下:
package com.android.services; import java.util.ArrayList; import android.os.Handler; import com.android.futils.task.FTaskPool; import com.android.futils.task.TaskItem; import com.android.handlers.ListViewHandle; import com.android.services.si.IListViewService; public class ListViewService implements IListViewService { String[] data={"加拿大","瑞典","澳大利亚","瑞士","新西兰","挪威","丹麦","芬兰","奥地利","荷兰","德国","日本","比利时","意大利","英国"}; public ListViewService() { // TODO Auto-generated constructor stub } private Handler handler=new Handler(); private ArrayList<String> msgs; @Override public void sendPost(int index, ListViewHandle handle) { // TODO Auto-generated method stub switch (index) { case 1: getData(index,handle); break; case 2: getData(index,handle); break; case 3: getData(index,handle); break; case 4: getData(index,handle); break; case 5: getData(index,handle); break; case 6: getData(index,handle); break; default: msgs=null; handle.getData(msgs); break; } } private synchronized void getData(final int index, final ListViewHandle handle) { // TODO Auto-generated method stub handler.postDelayed(new Runnable() { @Override public void run() { FTaskPool.getInstance().execute(new TaskItem() { @Override public void doMain() {//在前台显示数据 // TODO Auto-generated method stub if(handle!=null){ handle.getData(msgs); } } @Override public void doBack() {//在后台处理数据 // TODO Auto-generated method stub msgs=new ArrayList<String>(); for(String d:data){ msgs.add(index+"、"+d); } } }); } }, 2 * 1000);//延迟2秒后执行 } }
4、最后,我们来看下Fragment里面如来调用这个P层,来控制MV进行数据的获取以及更新
package com.android.fragment; import android.os.Bundle; import android.support.v4.app.Fragment; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import com.android.futilssimple.R; import com.android.presenters.ListViewPresenters; public class ListViewFragment extends Fragment { private ListViewPresenters listViewPresenters; public ListViewFragment() { } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View rootView = inflater.inflate(R.layout.listviewfragment, container, false); listViewPresenters=new ListViewPresenters(getActivity(), rootView);//新建一个控制器 listViewPresenters.onFindView();//初始化view listViewPresenters.setRefreshOrLoadMoreListem();//设置刷新监听 listViewPresenters.firstload();//首次自动上拉刷新 return rootView; } }
5、源码demo稍后上传
时间: 2024-12-11 19:50:13