最近更新2016.5.10(已经添加整个项目目录。更新新闻资讯)
本篇文章项目github地址:MVPCommon
本文章原地址:简书博客
1 前言
当然对于MVP的解说也是使用也是层出不穷,我也网络上也能看到各种版本的解说,之前博客也有文章的更新,里面有MVP的详细说明和项目代码—>Android中的MVP模式,带实例。
本篇文章将参考 google官方android MVP架构项目的实现,来实现自己的项目。或许看了这篇文章之后,你再去梳理一下google官方架构项目,会让你收获更多。官方的实例肯定具有更好的权威性。
推荐关注安卓各种架构相关文章合集github地址:AndroidArchitectureCollection
2 google官方MVP架构解析
1 项目目录
打开github,展开项目目录,会发现项目结构的组织方式是按照功能进行分模块的,当然根据个人情况,也可以按照ui,model,view,presenter这种情况进行划分组织目录。
2 具体实现流程
我们将关注度放到具体的一个taskdetail模块当中来解析实现MVP的流程。
2.1 TaskDetailContract
可以看到这里是通过一个协议类XXXContract来对View和Presenter的接口进行继承。这样做的好处也就是,我们可以将基础的View层的操作放在BaseView里面,对基础的Presenter层的操作放在BasePresenter里面。减少后续代码的重复。一个协议类也将View和Presenter管理起来,方便操作。
2.2 BaseView
那么来看看BaseView,主要是有一个setPresenter的操作,MVP中Presenter和View层是需要交互的,这里通过setPresenter操作,我们也就可以获得Presenter层的实例进行交互了。所以在我们自己的代码中,我们也可以将加载的loading,以及加载错误页面,加载失败页面等操作放在BaseView里面,这是每个View都会有的:
2.3 BasePresenter
BasePresenter中只有一个start方法,表示“开始”,我们可以在这里进行数据加载初始化等。
2.3 TaskDetailActivity
可以看到这里这里一个初始化了fragment的activity,主要操作当让是new了一个XXXPresenter。activity在项目中是一个全局的控制者,负责创建view以及presenter实例,并将二者联系起来,
2.4 TaskDetailFragment
Fragment是MVP中View的实现类,它不与Model 层进行交互,只和presenter的实例进行交互。
2.5 TaskDetailPresenter
Presenter的真正实现类,在这里进行model层和view层的交互。
通过上面的分析,在来梳理一下整个步骤:
1 官方MVP实例,通过协议类XXXContract来对View和Presenter的接口进行内部继承。是对BaseView和BasePresenter的进一步封装,所以我们实现的View和Presenter也只需要继承XXXContract中的对应内部接口就行。
**2 **activity的作用主要是创建View(这里是相应的fragment),以及创建presenter,并把view传递给presenter
3 在presenter的实现类的构造函数中,通过view的setPresenter,让view获得了presenter实例。这样view中就可以对Presenter中的方法进行操作了。
4 在presenter的实现类中,可以对Model数据进行操作。实例中,数据的获取、存储、数据状态变化都是model层的任务,presenter会根据需要调用该层的数据处理逻辑并在需要时将回调传入。这样model、presenter、view都只处理各自的任务,此种实现确实是单一职责最好的诠释。
3 实战应用:
说了这么多,通过一个主页面的搭建,来完整的使用MVP吧。
3.1 BaseView
我在这里没有添加setPresenter方法,而是将loading,以及加载错误,网络加载错误等页面都放在了这里面。
public interface BaseView {
// void setPresenter(P presenter);
void showLoading(String msg);
void hideLoading();
void showError(String msg, View.OnClickListener onClickListener);
void showEmpty(String msg, View.OnClickListener onClickListener);
void showEmpty(String msg, View.OnClickListener onClickListener, int imageId);
void showNetError(View.OnClickListener onClickListener);
}
3.2 BasePresenter
只有一个start方法。将在view界面初始化后调用(onResume方法中)
public interface BasePresenter {
void start();
}
3.3 DrawerMainContract
可以看到相比官方的实例我在其中添加了一个onGetDrawerListListener,主要是用于获取model层数据之后,进行数据的监听。
public interface DrawerMainContract {
interface Presenter extends BasePresenter{
//获取数据
void getDrawerList();
//头像点击
void onDrawerIconClicked();
//获取fragment
void getSelectFragment(int position);
}
interface View extends BaseView{
//获取数据后,更新界面
void onDrawerListGet(ArrayList<DrawerItemsData.DrawerItem> list);
//设置头像
void setDrawerIcon(int resId);
//fragment返回后
void onSelectFragmentGet(Fragment fragment);
}
//数据监听
interface onGetDrawerListListener {
void onSuccess();
void onError();
}
}
3.4 DrawerMainActivity
在开发中Fragment,Activity以及自定义view都可以作为MVP中View的实现。这里也在创建presenter实例的时候传入了当前view。并调用了 mPresenter.getDrawerList()进行获取数据,mPresenter.getSelectFragment(0);设置当前为第一个fragment。
/**
* Created by Anthony on 2016/5/3.
* Class Note:
* 1 use{@link DrawerLayout} to
* acts as a top-level container for window content that allows for
* interactive "drawer" views to be pulled out from the edge of the window.
* 2 View in MVP
* see {@link DrawerMainContract}------Manager role of MVP
* {@link DrawerMainPresenter}---------Presenter
* &{@link DrawerMainActivity}---------View
* &{@link DrawerItemsData}------------Model
*/
public class DrawerMainActivity extends AbsBaseActivity implements DrawerMainContract.View, View.OnClickListener {
private Toolbar actionBarToolbar;
public static DrawerLayout drawerLayout;
private ListView mDrawerMenu;
private CircleImageView mUserImg;
private NavDrawerListAdapter mAdapter;
private DrawerMainPresenter mPresenter;
@Override
protected int getContentViewID() {
return R.layout.activity_drawer;
}
@Override
protected void onResume() {
super.onResume();
mPresenter.start();
}
@Override
protected void initViewsAndEvents() {
super.initViewsAndEvents();//一定要调用super,进行父类中的一些初始化操作
initDrawerLayout();
setupToolBar();
//hide toolBar
ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
actionBar.hide();
}
mUserImg = (CircleImageView) findViewById(R.id.user_img);
mUserImg.setOnClickListener(this);
mDrawerMenu = (ListView) findViewById(R.id.left_menu);
// mPresenter = new DrawerMainPresenter(this, mContext);
//create and initialize presenter,
mPresenter= new DrawerMainPresenter(this,mContext);
//use presenter to load data
mPresenter.getDrawerList();
//default select first fragment
mPresenter.getSelectFragment(0);
}
protected void initDrawerLayout() {
drawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
if (drawerLayout == null) {
// current activity does not have a drawer.
return;
}
if (getDrawerLayoutId() != 0) {
FrameLayout leftLayout = (FrameLayout) findViewById(R.id.left_drawer_layout);
View nav_drawer_layout = getLayoutInflater().inflate(getDrawerLayoutId(), null);
leftLayout.addView(nav_drawer_layout);
}
}
protected void setupToolBar() {
if (actionBarToolbar == null) {
actionBarToolbar = (Toolbar) findViewById(R.id.toolbar);
if (actionBarToolbar != null) {
setSupportActionBar(actionBarToolbar);
}
}
final ActionBar ab = getSupportActionBar();
if (ab == null)
return;
ab.setHomeAsUpIndicator(R.drawable.ic_menu);
ab.setDisplayHomeAsUpEnabled(true);
}
public static void openDrawer() {
if (drawerLayout == null)
return;
drawerLayout.openDrawer(GravityCompat.START);
}
public static void closeDrawer() {
if (drawerLayout == null)
return;
drawerLayout.closeDrawer(GravityCompat.START);
}
/**
* close drawer if drawer is opening
*/
@Override
public void onBackPressed() {
if (drawerLayout.isDrawerOpen(GravityCompat.START)) {
closeDrawer();
} else {
super.onBackPressed();
}
}
protected int getDrawerLayoutId() {
return R.layout.nav_drawer_layout;
}
@Override
public void onClick(View v) {
if (v.getId() == R.id.user_img) {
mPresenter.onDrawerIconClicked();
}
}
@Override
public void onDrawerListGet(final ArrayList<DrawerItemsData.DrawerItem> mDrawerItems) {
mAdapter = new NavDrawerListAdapter(this,
mDrawerItems);
mDrawerMenu.setAdapter(mAdapter);
mDrawerMenu.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
if (!BaseUtil.isEmpty(mDrawerItems, i)) {
DrawerItemsData.DrawerItem drawerItem = mDrawerItems.get(i);
if (drawerItem != null) {
mPresenter.getSelectFragment(i);
}
}
}
});
}
@Override
public void setDrawerIcon(int resId) {
mUserImg.setImageResource(resId);
}
@Override
public void onSelectFragmentGet(Fragment fragment) {
closeDrawer();
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction()
.replace(R.id.content, fragment).commit();
}
@Override
protected void onNetworkConnected(NetUtils.NetType type) {
ToastUtils.getInstance().showToast("this type is"+type);
}
@Override
protected void onNetworkDisConnected() {
ToastUtils.getInstance().showToast("no network disconnected");
}
@Override
protected View getLoadingTargetView() {
return null;
}
// @Override
// public void setPresenter(DrawerMainContract.Presenter presenter) {
// mPresenter= (DrawerMainPresenter) presenter;
// }
@Override
public void showLoading(String msg) {
toggleShowLoading(true, msg);
}
@Override
public void hideLoading() {
toggleShowLoading(false, "");
}
@Override
public void showError(String msg, View.OnClickListener onClickListener) {
}
@Override
public void showEmpty(String msg, View.OnClickListener onClickListener) {
toggleShowEmpty(true, msg, onClickListener);
}
@Override
public void showEmpty(String msg, View.OnClickListener onClickListener, int imageId) {
toggleShowEmpty(true, msg, onClickListener, imageId);
}
@Override
public void showNetError(View.OnClickListener onClickListener) {
ToastUtils.getInstance().showToast("oops ,no network now!");
}
}
这里也实现了DrawerMainContract.View以及BaseView中的所有方法。
3.5 DrawerMainPresenter
对DrawerMainContract.Presenter和DrawerMainContract.
onGetDrawerListListener的实现。
可以看到DrawerItemsData就是model层的对象。主要封装的是本地的字符串和图片数据。
/**
* Created by Anthony on 2016/5/3.
* Class Note: Presenter in MVP
* see {@link DrawerMainContract}--------Manager role of MVP
* &{@link DrawerMainPresenter}------Presenter
* &{@link DrawerMainActivity}-------------View
* &{@link DrawerItemsData}-----------Model
*/
public class DrawerMainPresenter implements DrawerMainContract.Presenter, DrawerMainContract.onGetDrawerListListener {
private DrawerMainContract.View mView;
private Context mContext;
private DrawerItemsData mData;
public DrawerMainPresenter(DrawerMainContract.View mView, Context mContext) {
this.mContext = mContext;
this.mView = mView;
// mView.setPresenter(this);//bind presenter for View
mData = new DrawerItemsData(mContext, this);//bind data listener for Model
}
@Override
public void onDrawerIconClicked() {
//已经登录,跳到个人详情页
ToastUtils.getInstance().showToast("icon clicked");
//没有登录 ,则跳到登录页面。。。
}
@Override
public void getDrawerList() {
mData.initItemsData();
}
@Override
public void getSelectFragment(int position) {
if (position == 3)
mView.onSelectFragmentGet(new NewsChannelFragment());
else mView.onSelectFragmentGet(new TestFragment());
}
@Override
public void onSuccess() {
mView.onDrawerListGet(mData.mDrawerItems);
mView.setDrawerIcon(R.drawable.icon_head);
}
@Override
public void onError() {
// show error view
mView.showNetError(new View.OnClickListener() {
@Override
public void onClick(View v) {
}
});
}
@Override
public void start() {
}
}
3.6 DrawerItemsData
这就是我主页面的model层的数据,当然后面可能会对这些数据进行修改,或者添加上网络访问。但是你会发现再也不用像以前那样要去修改整个activity了,只需要的是修改这个类。这也是MVP的作用,单一职责。
/**
* Created by Anthony on 2016/5/3.
* Class Note:
* drawer list item data.
*
*/
public class DrawerItemsData {
private Context mContext;
public ArrayList<DrawerItem> mDrawerItems;
private String[] mMenuTitles;
private TypedArray mMenuIconsTypeArray;
private TypedArray mMenuIconTintTypeArray;
private DrawerMainContract.onGetDrawerListListener mListener;
public DrawerItemsData(Context context, DrawerMainContract.onGetDrawerListListener listener) {
this.mContext = context;
this.mListener =listener;
mDrawerItems=new ArrayList<>();
}
public void initItemsData() {
mMenuTitles = mContext.getResources().getStringArray(R.array.nav_drawer_items);
// nav drawer icons from resources
mMenuIconsTypeArray = mContext.getResources()
.obtainTypedArray(R.array.nav_drawer_icons);
mMenuIconTintTypeArray = mContext.getResources()
.obtainTypedArray(R.array.nav_drawer_tint);
for (int i = 0; i < mMenuTitles.length; i++) {
mDrawerItems.add(new DrawerItem(mMenuTitles[i], mMenuIconsTypeArray
.getResourceId(i, -1), mMenuIconTintTypeArray.getResourceId(i, -1)));
}
mMenuIconsTypeArray.recycle();
if(mDrawerItems.size()==mMenuTitles.length){
mListener.onSuccess();
}else{
mListener.onError();
}
}
public class DrawerItem {
private String title;
private int icon;
//图片颜色
private int tint;
private String count = "0";
// boolean to set visiblity of the counter
private boolean isCounterVisible = false;
public DrawerItem(){}
public DrawerItem(String title, int icon, int tint){
this.title = title;
this.icon = icon;
this.tint = tint;
}
public DrawerItem(String title, int icon, boolean isCounterVisible, String count){
this.title = title;
this.icon = icon;
this.isCounterVisible = isCounterVisible;
this.count = count;
}
public String getTitle(){
return this.title;
}
public int getIcon(){
return this.icon;
}
public String getCount(){
return this.count;
}
public boolean getCounterVisibility(){
return this.isCounterVisible;
}
public void setTitle(String title){
this.title = title;
}
public void setIcon(int icon){
this.icon = icon;
}
public void setCount(String count){
this.count = count;
}
public int getTint() {
return tint;
}
public void setTint(int tint) {
this.tint = tint;
}
public void setCounterVisibility(boolean isCounterVisible){
this.isCounterVisible = isCounterVisible;
}
}
}
具体请参看本篇文章项目github地址:MVPCommon