学习使用Material Design控件（四）Android实现标题栏自动缩放、放大效果

<?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”
  android:layout_width=“match_parent”
  android:layout_height=“match_parent”
  android:fitsSystemWindows=“true”>

  <android.support.design.widget.AppBarLayout
    android:layout_width=“match_parent”
    android:layout_height=“256dp”
    android:fitsSystemWindows=“true”
    android:theme=“@style/ThemeOverlay.AppCompat.Dark.ActionBar”>

    <android.support.design.widget.CollapsingToolbarLayout
      android:id=“@+id/collapsing_toolbar”
      android:layout_width=“match_parent”
      android:layout_height=“match_parent”
      android:fitsSystemWindows=“true”
      app:contentScrim=“?attr/colorPrimary”
      app:expandedTitleMarginEnd=“64dp”
      app:expandedTitleMarginStart=“48dp”
      app:layout_scrollFlags=“scroll|exitUntilCollapsed”>

      <ImageView
        android:id=“@+id/ivImage”
        android:layout_width=“match_parent”
        android:layout_height=“match_parent”
        android:fitsSystemWindows=“true”
        android:scaleType=“centerCrop”
        android:src=“@drawable/book1”
        app:layout_collapseMode=“parallax”
        app:layout_collapseParallaxMultiplier=“0.7” />

      <android.support.v7.widget.Toolbar
        android:id=“@+id/toolbar”
        android:layout_width=“match_parent”
        android:layout_height=“?attr/actionBarSize”
        app:layout_collapseMode=“pin”
        app:popupTheme=“@style/ThemeOverlay.AppCompat.Light” />


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

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

  <LinearLayout
    android:layout_width=“match_parent”
    android:layout_height=“match_parent”
    android:orientation=“vertical”
    app:layout_behavior=“@string/appbar_scrolling_view_behavior”>

    <android.support.design.widget.TabLayout
      android:id=“@+id/sliding_tabs”
      android:layout_width=“match_parent”
      android:layout_height=“wrap_content”
      app:tabGravity=“fill”
      app:tabMode=“fixed” />

    <android.support.v4.view.ViewPager
      android:id=“@+id/viewpager”
      android:layout_width=“match_parent”
      android:layout_height=“match_parent” />
  </LinearLayout>
</android.support.design.widget.CoordinatorLayout>

//Toolbar
 Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
 setSupportActionBar(toolbar);
 getSupportActionBar().setDisplayHomeAsUpEnabled(true);
 toolbar.setNavigationOnClickListener(new View.OnClickListener() {
   @Override
   public void onClick(View view) {
     onBackPressed();
   }
 });

//使用CollapsingToolbarLayout后，title需要设置到CollapsingToolbarLayout上
 CollapsingToolbarLayout collapsingToolbar = (CollapsingToolbarLayout) findViewById(R.id.collapsing_toolbar);
 collapsingToolbar.setTitle("失控");

//设置ViewPager
 mViewPager = (ViewPager) findViewById(R.id.viewpager);
 setupViewPager(mViewPager);

//给TabLayout增加Tab, 并关联ViewPager
 TabLayout tabLayout = (TabLayout) findViewById(R.id.sliding_tabs);
 tabLayout.addTab(tabLayout.newTab().setText("内容简介"));
 tabLayout.addTab(tabLayout.newTab().setText("作者简介"));
 tabLayout.addTab(tabLayout.newTab().setText("目录"));
 tabLayout.setupWithViewPager(mViewPager);