android之MVP设计模式详解

       MVP是微软提出的一种架构设计模式。在android应用的开发中目前使用非常广泛。分别为Modle:业务逻辑，View:视图，Presenter:中间着。（用于绑定Modle和View）Modle用来加载数据，View用来显示数据，Presenter用来绑定Modle和View的联系。

     下面来看具体的代码实现:

  一，上图看一下简单的项目结构

    


 二，定义一个GirlModle接口

/**
* Created by 晁东洋 on 2016/10/9.
*/

public interface GirleModle {
//加载数据
void loadGirl( GirlonLoadListener loadListener);
//加载完成的监听
interface GirlonLoadListener{
void onComplate(List<Girl> list);
}
}

三，定义一个GrilView的接口

/**
* Created by 晁东洋 on 2016/10/9.
*/

public interface GirlView {
//加载进度条
void showLoading();
//加载数据
void showGilrs(List<Girl> list);
}

四，定义一个Gril的bean数据源

package com.hdceping.www.mytest.bean;

/**
* Created by 晁东洋 on 2016/10/9.
*/

public class Girl {
private String imageUrl;
private String title;
private String name;

public String getImageUrl() {
return imageUrl;
}

public void setImageUrl(String imageUrl) {
this.imageUrl = imageUrl;
}

public String getTitle() {
return title;
}

public void setTitle(String title) {
this.title = title;
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public Girl(String imageUrl, String title, String name) {
this.imageUrl = imageUrl;
this.title = title;
this.name = name;
}
}

五，定义GrileModleImpl类，实现GrileModel接口。
   

package com.hdceping.www.mytest.modle.impl;

import com.hdceping.www.mytest.bean.Girl;
import com.hdceping.www.mytest.modle.GirleModle;

import java.util.ArrayList;
import java.util.List;

/**
* Created by 晁东洋 on 2016/10/9.
*/

public class GirleModleImpl implements GirleModle {

@Override
public void loadGirl(GirlonLoadListener loadListener) {
List<Girl> data = new ArrayList<>();
data.add(new Girl("http://a4.topitme.com/o/201012/20/12928333231233.jpg","图片","美女图片"));
data.add(new Girl("http://tp.85814.com/d/file/meinv/2016-10-09/100567-coL4Krz.jpg","图片","美女图片"));
data.add(new Girl("http://tp.85814.com/d/file/meinv/2016-10-09/100567-rtUVwh5.jpg","图片","美女图片"));
data.add(new Girl("http://tp.85814.com/d/file/meinv/2016-05-31/77772-Qu2Dx3h.jpg","图片","美女图片"));
data.add(new Girl("http://tp.85814.com/d/file/meinv/2016-10-09/100567-Olhb7Ll.jpg","图片","美女图片"));
data.add(new Girl("http://tp.85814.com/d/file/meinv/2016-10-09/100567-coL4Krz.jpg","图片","美女图片"));
data.add(new Girl("http://tp.85814.com/d/file/meinv/2016-10-09/100567-rtUVwh5.jpg","图片","美女图片"));
data.add(new Girl("http://tp.85814.com/d/file/meinv/2016-05-31/77772-Qu2Dx3h.jpg","图片","美女图片"));
//回掉完成监听
loadListener.onComplate(data);
}

}

六，定义GrilPersenter类，实现业务逻辑和View的绑定：
 

package com.hdceping.www.mytest.persenter;

import com.hdceping.www.mytest.bean.Girl;
import com.hdceping.www.mytest.modle.GirleModle;
import com.hdceping.www.mytest.modle.impl.GirleModleImpl;
import com.hdceping.www.mytest.view.GirlView;

import java.util.List;

/**
* Created by 晁东洋 on 2016/10/9.
*/

public class GirlPersenter {
GirlView mGirlView;
GirleModle mGirleModle = new GirleModleImpl();

public GirlPersenter(GirlView girlView) {
mGirlView = girlView;
}
public void fetch(){
//显示进度条
mGirlView.showLoading();
//加载数据
if (mGirleModle != null){
mGirleModle.loadGirl(new GirleModle.GirlonLoadListener() {
@Override
public void onComplate(List<Girl> list) {
mGirlView.showGilrs(list);
}
});
}
}
}

七，MainActivity类。

package com.hdceping.www.mytest;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.Toast;

import com.hdceping.www.mytest.adapter.ListGirlAdapter;
import com.hdceping.www.mytest.bean.Girl;
import com.hdceping.www.mytest.persenter.GirlPersenter;
import com.hdceping.www.mytest.view.GirlView;

import java.util.List;

public class MainActivity extends AppCompatActivity implements GirlView{

private ListView mListView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mListView = (ListView) findViewById(R.id.mvp_Listview);
new GirlPersenter(this).fetch();
}

@Override
public void showLoading() {
Toast.makeText(this,"拼命加载中",Toast.LENGTH_LONG);
}

@Override
public void showGilrs(List<Girl> list) {
mListView.setAdapter(new ListGirlAdapter(this,this,list));
}
}

八，我的布局文件。
 

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.hdceping.www.mytest.MainActivity">

<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/mvp_Listview"></ListView>
</RelativeLayout>

九，adapter的代码：
 

package com.hdceping.www.mytest.adapter;

import android.app.Activity;
import android.content.Context;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import com.bumptech.glide.Glide;
import com.bumptech.glide.load.resource.drawable.GlideDrawable;
import com.bumptech.glide.request.RequestListener;
import com.bumptech.glide.request.target.Target;
import com.hdceping.www.mytest.R;
import com.hdceping.www.mytest.bean.Girl;

import java.util.List;

/**
* Created by 晁东洋 on 2016/10/9.
*/

public class ListGirlAdapter extends BaseAdapter {
private LayoutInflater mInflater;
private List<Girl> mList;
private Activity mActivity;
private Context mContext;

public ListGirlAdapter(Activity activity, Context mContext, List<Girl> list) {
mInflater = LayoutInflater.from(mContext);
mList = list;
mActivity = activity;
this.mContext  = mContext;
}

@Override
public int getCount() {
return mList.size();
}

@Override
public Object getItem(int position) {
return mList.get(position);
}

@Override
public long getItemId(int position) {
return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder viewHolder =null;
if (viewHolder == null){
convertView = mInflater.inflate(R.layout.layout_item,null);
viewHolder = new ViewHolder();
viewHolder.imageview_mvp = (ImageView)convertView.findViewById(R.id.imageview_mvp);
viewHolder.text_mvp = (TextView)convertView.findViewById(R.id.text_mvp);
viewHolder.text2_mvp = (TextView)convertView.findViewById(R.id.text2_mvp);
convertView.setTag(viewHolder);
}else {
viewHolder = (ViewHolder)convertView.getTag();

}
Log.e("网络地址",mList.get(position).getImageUrl());
Glide.with(mContext).load(mList.get(position).getImageUrl()).listener(mRequestListener).error(R.mipmap.ic_launcher).into(viewHolder.imageview_mvp);
viewHolder.text_mvp.setText(mList.get(position).getTitle());
viewHolder.text2_mvp.setText(mList.get(position).getName());
return convertView;
}

private RequestListener<String, GlideDrawable> mRequestListener = new RequestListener<String, GlideDrawable>() {
@Override
public boolean onException(Exception e, String model, Target<GlideDrawable> target, boolean isFirstResource) {
//显示错误信息
Log.e("TAG", "onException: ", e);
//打印请求URL
Log.e("TAG", "onException: " + model);
//打印请求是否还在进行
Log.e("TAG", "onException: " + target.getRequest().isRunning());
return false;
}

@Override
public boolean onResourceReady(GlideDrawable resource, String model, Target<GlideDrawable> target, boolean isFromMemoryCache, boolean isFirstResource) {
return false;
}
};

class ViewHolder{
private ImageView imageview_mvp;
private TextView  text_mvp;
private TextView  text2_mvp;
}
}

   大家可以看到MVP设计模式，其实有大量的接口和回掉编写代码。主要是设计思路。仔细看还是能看看懂的。如果有问题一起探讨。