手把手教你打造一个Material Design风格的App(二)

1、手把手教你打造一个Material Design风格的App(三)3.2添加抽屉导航添加导航抽屉跟Android 5.0之前是一样的，只是以前我们使用ListView来作为菜单容器，现在我们则使用Material Design风格的RecyclerView。（14）在你工程的Java文件夹中，创建3个名为activity、adapter、model的包，将MainActivity.java移到activtiy包中，这样做使得你的代码可以很好地组织和管理。（15）打开位于app模块下的build.gradle文件并添加如下依赖。添加完依赖之后，点击Build-Rebuild Project下载所

2、需要的类库。html view plain copybuild.gradle dependencies compile fileTree(dir: libs, include: *.jar) compile com.android.support:appcompat-v7:22.0.0 compile com.android.support:recyclerview-v7:21.0.+ （16）在model包里，创建名为NavDrawerItem.java的类，然后添加以下代码。这个模型类是一个简单的POJO（Plain Oridinary Java Object即简单的java对象）类，它定

3、义了导航抽屉的菜单项。java view plain copyNavDrawerItem.java package .materialdesign.model; public class NavDrawerItem private boolean showNotify; private String title; public NavDrawerItem() public NavDrawerItem(boolean showNotify, String title) this.showNotify = showNotify; this.title = title

4、; public boolean isShowNotify() return showNotify; public void setShowNotify(boolean showNotify) this.showNotify = showNotify; public String getTitle() return title; public void setTitle(String title) this.title = title; （17）在res-layout下，创建一个名为nav_drawer_row.xml的文件并添加如下代码。这个布局渲染了导航抽屉菜单的每一行，如果你想自定义抽屉

5、菜单项，你需要修改这个布局文件。在这个例子中，它仅包含一个TextView。html view plain copynav_drawer_row.xml android:layout_width=match_parent android:layout_height=wrap_content android:clickable=true （18）下载个人资料图标并将它放入drawable文件夹，这一步是可选的，但是这个图标会在导航抽屉的头部用到。（19）创建另一个名为fragment_navigation_drawer.xml的布局文件并添加如下代码。这个布局文件渲染了整个导航抽屉的视图，这个布

6、局包括一个显示个人信息的头部和一个显示列表的RecycleView。html view plain copyfragment_navigation_drawer.xml android:layout_width=match_parent android:layout_height=match_parent android:background=android:color/white （20）因为RecycleView是自定义的，我们还需要一个adapter来渲染自定义的xml布局，所以在adapter包下面，创建一个名为NavgationDrawerAdapter.java的类并添加如下代码。

7、这个适配器类inflate了nav_drawer_row.xml并渲染了RecycleView抽屉菜单。java view plain copyimport android.content.Context; import android.support.v7.widget.RecyclerView; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.TextView; import java.util.Collect

8、ions; import java.util.List; /* * Created by Ravi Tamada on 12-03-2015. */ public class NavigationDrawerAdapter extends RecyclerView.Adapter List data = Collections.emptyList(); private LayoutInflater inflater; private Context context; public NavigationDrawerAdapter(Context context, List data) this.

9、context = context; inflater = LayoutInflater.from(context); this.data = data; public void delete(int position) data.remove(position); notifyItemRemoved(position); Override public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) View view = inflater.inflate(R.layout.nav_drawer_row, par

10、ent, false); MyViewHolder holder = new MyViewHolder(view); return holder; Override public void onBindViewHolder(MyViewHolder holder, int position) NavDrawerItem current = data.get(position); holder.title.setText(current.getTitle(); Override public int getItemCount() return data.size(); class MyViewH

11、older extends RecyclerView.ViewHolder TextView title; public MyViewHolder(View itemView) super(itemView); title = (TextView) itemView.findViewById(R.id.title); （21）在activity包下，创建一个名为FragmentDrawer.java的Fragment。在Android Studio里面，按以下操作来创建一个新的Fragment，在activity包上右键-New-Fragment-Fragment(Blank)，然后给Frag

12、ment命名。java view plain copyFragmentDrawer.java import android.content.Context; import android.content.res.TypedArray; import android.os.Bundle; import android.support.v4.app.Fragment; import android.support.v4.widget.DrawerLayout; import android.support.v7.app.ActionBarDrawerToggle; import android.s

13、upport.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import android.support.v7.widget.Toolbar; import android.view.GestureDetector; import android.view.LayoutInflater; import android.view.MotionEvent; import android.view.View; import android.view.ViewGroup; import and

14、roid.widget.LinearLayout; import android.widget.TextView; import java.util.ArrayList; import java.util.List; public class FragmentDrawer extends Fragment private static String TAG = FragmentDrawer.class.getSimpleName(); private RecyclerView recyclerView; private ActionBarDrawerToggle mDrawerToggle;

15、private DrawerLayout mDrawerLayout; private NavigationDrawerAdapter adapter; private View containerView; private static String titles = null; private FragmentDrawerListener drawerListener; public FragmentDrawer() public void setDrawerListener(FragmentDrawerListener listener) this.drawerListener = li

16、stener; public static List getData() List data = new ArrayList(); / preparing navigation drawer items for (int i = 0; i titles.length; i+) NavDrawerItem navItem = new NavDrawerItem(); navItem.setTitle(titlesi); data.add(navItem); return data; Override public void onCreate(Bundle savedInstanceState)

17、super.onCreate(savedInstanceState); / drawer labels titles = getActivity().getResources().getStringArray(R.array.nav_drawer_labels); Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) / Inflating view layout View layout = inflater.inflate(R.lay

18、out.fragment_navigation_drawer, container, false); recyclerView = (RecyclerView) layout.findViewById(R.id.drawerList); adapter = new NavigationDrawerAdapter(getActivity(), getData(); recyclerView.setAdapter(apter); recyclerView.setLayoutManager(new LinearLayoutManager(getActivity(); recyclerView.add

19、OnItemTouchListener(new RecyclerTouchListener(getActivity(), recyclerView, new ClickListener() Override public void onClick(View view, int position) drawerListener.onDrawerItemSelected(view, position); mDrawerLayout.closeDrawer(containerView); Override public void onLongClick(View view, int position

20、) ); return layout; public void setUp(int fragmentId, DrawerLayout drawerLayout, final Toolbar toolbar) containerView = getActivity().findViewById(fragmentId); mDrawerLayout = drawerLayout; mDrawerToggle = new ActionBarDrawerToggle(getActivity(), drawerLayout, toolbar, R.string.drawer_open, R.string

21、.drawer_close) Override public void onDrawerOpened(View drawerView) super.onDrawerOpened(drawerView); getActivity().invalidateOptionsMenu(); Override public void onDrawerClosed(View drawerView) super.onDrawerClosed(drawerView); getActivity().invalidateOptionsMenu(); Override public void onDrawerSlid

22、e(View drawerView, float slideOffset) super.onDrawerSlide(drawerView, slideOffset); toolbar.setAlpha(1 - slideOffset / 2); ; mDrawerLayout.setDrawerListener(mDrawerToggle); mDrawerLayout.post(new Runnable() Override public void run() mDrawerToggle.syncState(); ); public static interface ClickListene

23、r public void onClick(View view, int position); public void onLongClick(View view, int position); static class RecyclerTouchListener implements RecyclerView.OnItemTouchListener private GestureDetector gestureDetector; private ClickListener clickListener; public RecyclerTouchListener(Context context,

24、 final RecyclerView recyclerView, final ClickListener clickListener) this.clickListener = clickListener; gestureDetector=newGestureDetector(context,new GestureDetector.SimpleOnGestureListener() Override public boolean onSingleTapUp(MotionEvent e) return true; Override public void onLongPress(MotionE

25、vent e) View child = recyclerView.findChildViewUnder(e.getX(), e.getY(); if (child != null & kListener != null) clickListener.onLongClick(child, recyclerView.getChildPosition(child); ); Override public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) View child = rv.findChildViewUnder(e

26、.getX(), e.getY(); if (child != null & clickListener != null & gestureDetector.onTouchEvent(e) clickListener.onClick(child, rv.getChildPosition(child); return false; Override public void onTouchEvent(RecyclerView rv, MotionEvent e) public interface FragmentDrawerListener public void onDrawerItemSele

27、cted(View view, int position); （22）最后打开主Activity的布局文件（activity_main.xml）并按下面所示来修改布局。在这个布局里面，我们添加了android.support.v4.widget.DrawerLayout来展示导航抽屉菜单。当然在标签里，你需要给出fragmentDrawer正确的路径。html view plain copyactiivty_main.xml android:id=+id/drawer_layout android:layout_width=match_parent android:layout_height=

28、match_parent 现在所有的布局文件和java类文件都准备到位了，让我们对MainActivity做一些修改来使导航抽屉工作起来。（23）打开MainActivity.java文件并做如下修改。实现FragmentDrawer.FragmentDrawerListener接口并添加onDrawerItemSelected()重载。java view plain copyMainActivity.java import android.support.v4.widget.DrawerLayout; import android.support.v7.app.ActionBarActivi

29、ty; import android.os.Bundle; import android.support.v7.widget.Toolbar; import android.view.Menu; import android.view.MenuItem; import android.view.View; publicclassMainActivityextendsActionBarActivityimplements FragmentDrawer.FragmentDrawerListener private Toolbar mToolbar; private FragmentDrawer drawerFragment; Override protected void onCreate(Bundle savedInstanceState) super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); mToolbar = (Toolbar) findViewById(R.id.toolbar); setSupportActionBar(mToolbar); getSupportActi