Android Support Library 标题栏(Toolbar)滚动效果实现方法

首先来个效果图  

 布局文件代码

在布局文件中，CoordinatorLayout作为布局文件根节点，AppBarLayout包含在CoordinatorLayout中，toolbar在AppBarLayout节点下include进来。

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout 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:layout_width="match_parent"
 android:layout_height="match_parent"
 tools:context="cn.manchester.androidsupportlibrary.CoordinatorLayoutActivity">

<android.support.design.widget.AppBarLayout
   android:id="@+id/appbar"
   android:layout_width="match_parent"
   android:layout_height="wrap_content"
   android:fitsSystemWindows="true">
   <include layout="@layout/toolbar" />
 </android.support.design.widget.AppBarLayout>

<LinearLayout
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:orientation="vertical"
   android:scrollbars="none"
   app:layout_behavior="@string/appbar_scrolling_view_behavior">

<android.support.v7.widget.RecyclerView
     android:id="@+id/recyclerView"
     android:layout_width="match_parent"
     android:layout_height="match_parent" />

</LinearLayout>

</android.support.design.widget.CoordinatorLayout>

toolbar.xml

toolbar是需要响应view的滚动事件的，所以需要为toolbar指定layout_scrollFlags属性，scroll表示toobar会随着view的向下滚动而隐藏，enterAlways表示toolbar会随着view的向上滚动而恢复到原来的位置。

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:app="http://schemas.android.com/apk/res-auto"
 android:id="@+id/toolbar"
 android:layout_width="match_parent"
 android:layout_height="wrap_content"
 android:background="#304696"
       android:popupTheme="@style/ThemeOverlay.AppCompat.Light"
 app:layout_scrollFlags="scroll|enterAlways"
 app:theme="@style/ThemeOverlay.AppCompat.ActionBar">

</android.support.v7.widget.Toolbar>

Java代码

public class CoordinatorLayoutActivity extends AppCompatActivity {
 Toolbar mToolbar;

RecyclerView mRecyclerView;
 String[] mArrays = new String[]{"1", "2", "3", "4", "5", "6", "7", "8", "9", "10", "11", "12", "13", "14"};
 @Override
 protected void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);
   setContentView(R.layout.activity_coordinator_layout);
   mToolbar = (Toolbar) findViewById(R.id.toolbar);
   setSupportActionBar(mToolbar);
   getSupportActionBar().setDisplayHomeAsUpEnabled(true);

mRecyclerView = (RecyclerView) findViewById(R.id.recyclerView);
   mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
   mRecyclerView.setAdapter(new MyAdapter());
 }

class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {

@Override
   public MyAdapter.MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
     MyViewHolder holder = new MyViewHolder(LayoutInflater.from(CoordinatorLayoutActivity.this)
         .inflate(android.R.layout.simple_list_item_1, parent, false));
     return holder;
   }

@Override
   public void onBindViewHolder(MyAdapter.MyViewHolder holder, int position) {
     holder.tv.setText(mArrays[position]);
   }

@Override
   public int getItemCount() {
     return mArrays.length;
   }

class MyViewHolder extends RecyclerView.ViewHolder {

TextView tv;

public MyViewHolder(View itemView) {
       super(itemView);
       tv = (TextView) itemView.findViewById(android.R.id.text1);
     }

}
 }
}