仿照着知乎写了一套UI界面,结合着以前学的知识,一天就撸了出来,其实也没啥东西,就是有些没接触的地方踩了坑。
效果展示
涉及知识点
- 最基础的viewpager编写可以参看这篇超简单ViewPager控件实现Demo
- tablayout+viewpager实现的过程可以参看这篇Material Design学习:TabLayout+Viewpager制作一个标签页
- recycleview的实现可以参看这篇RecyclerView的使用简介
- viewpager需要添加为recycleview的头布局才能在recycleview上滑的时候上滑,但是recycleview没有添加头布局方法,具体的实现是通过加载不同item的方式。
可以参看我写的RecycleView加载不同类型的Item
页面分析
实现思路
- 外层的viewpager页面,通过点击页面底部的RadioButton来进行页面切换(禁止此viewpager响应滑动事件),配合fragment实现。
- 中间层的viewpager页面,通过和tablayout绑定,配合fragment,实现顶部页签。
- 顶层的viewpager页面,就是个简单的轮播图,循环播放不想写了。底部使用了viewpagerindicator开源库实现小圆点指示器。
- 添加依赖
compile 'com.android.support:design:24.2.0'
compile 'com.android.support:cardview-v7:24.2.0'
compile 'com.android.support:recyclerview-v7:24.2.0'
viewpagerindicator开源库可以从我的项目中下载
1. 外层viewpager的布局实现
- 布局代码实现
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<zhj.viewpagerdemo.view.NoScrollViewPager
android:id="@+id/vp_main"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"/>
<RadioGroup
android:id="@+id/rg_group"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:paddingTop="5dp">
<RadioButton
android:id="@+id/rb_home"
style="@style/BottomTabStyle"
android:checked="true"
android:drawableBottom="@drawable/btn_tab_home_selector"/>
<RadioButton
android:id="@+id/rb_news"
style="@style/BottomTabStyle"
android:drawableBottom="@drawable/btn_tab_news_selector"/>
<RadioButton
android:id="@+id/rb_service"
style="@style/BottomTabStyle"
android:drawableBottom="@drawable/btn_tab_service_selector"/>
<RadioButton
android:id="@+id/rb_gov"
style="@style/BottomTabStyle"
android:drawableBottom="@drawable/btn_tab_gov_selector"/>
<RadioButton
android:id="@+id/rb_setting"
style="@style/BottomTabStyle"
android:drawableBottom="@drawable/btn_tab_setting_selector"/>
</RadioGroup>
</LinearLayout>
- 禁止滑动的viewpager实现,继承viewpager
public class NoScrollViewPager extends ViewPager {
public NoScrollViewPager(Context context) {
super(context);
}
public NoScrollViewPager(Context context, AttributeSet attrs) {
super(context, attrs);
}
//表示事件是否拦截,返回false表示不拦截
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
return false;
}
//重写onTouchEvent事件,什么都不用做
@Override
public boolean onTouchEvent(MotionEvent ev) {
return false;
}
}
2. 外层viewpager的代码实现
public class MainActivity extends AppCompatActivity {
private MyFragmentPagerAdapter myFragmentPagerAdapter;
private RadioGroup rgGroup;
private List<Fragment> fragments;
private ViewPager mViewPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
supportRequestWindowFeature(Window.FEATURE_NO_TITLE); //隐藏掉系统原先的导航栏
setContentView(R.layout.activity_main);
mViewPager = (ViewPager) findViewById(R.id.vp_main);
//新建fragment集合对象,传递给FragmentPagerAdapter
fragments=new ArrayList<Fragment>();
fragments.add(new Fragment1());
fragments.add(new Fragment2());
fragments.add(new Fragment3());
fragments.add(new Fragment4());
fragments.add(new Fragment5());
myFragmentPagerAdapter = new MyFragmentPagerAdapter(getSupportFragmentManager(),fragments);
mViewPager.setAdapter(myFragmentPagerAdapter);
rgGroup = (RadioGroup) findViewById(R.id.rg_group);
rgGroup.check(R.id.rb_home);
//当点击底部按钮时切换页面
rgGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup radioGroup, int i) {
if (i == R.id.rb_home) {
mViewPager.setCurrentItem(0, false);//去掉切换页面的动画
} else if (i == R.id.rb_news) {
mViewPager.setCurrentItem(1, false);
} else if (i == R.id.rb_service) {
mViewPager.setCurrentItem(2, false);
} else if (i == R.id.rb_gov) {
mViewPager.setCurrentItem(3, false);
} else if (i == R.id.rb_setting) {
mViewPager.setCurrentItem(4, false);
}
}
});
//防止频繁的销毁视图
mViewPager.setOffscreenPageLimit(4);
}
}
在大部分时候,项目中的ViewPager会和Fragment同时出现,每一个ViewPager的页面就是一个Fragment。
Android提供了一些专门的适配器来让ViewPager与Fragment一起工作,也就是FragmentPagerAdapter与FragmentStatePagerAdapter。
FragmentPagerAdapter继承自PagerAdapter ,主要用来展示多个Fragment页面,并且每一个Fragment都会被保存在fragment manager中。
FragmentPagerAdapter最适用于那种少量且相对静态的页面,例如几个tab页。每一个用户访问过的fragment都会被保存在内存中,尽管他的视图层级可能会在不可见时被销毁。这可能导致大量的内存因为fragment实例能够拥有任意数量的状态。对于较多的页面集合,更推荐使用FragmentStatePagerAdapter。
当使用FragmentPagerAdapter的时候对应的ViewPager必须拥有一个有效的ID集。
FragmentPagerAdapter的派生类只需要实现getItem(int)和getCount()即可。
- FragmentPagerAdapter适配器的实现
public class MyFragmentPagerAdapter extends FragmentPagerAdapter{
private List<Fragment> fragments;
public MyFragmentPagerAdapter(FragmentManager fm,List<Fragment> fragments) {
super(fm);
this.fragments=fragments;
}
@Override
public Fragment getItem(int position) {
return fragments.get(position);
}
@Override
public int getCount() {
return fragments.size();
}
}
里面的几个fragment都是简单布局,就不贴了。主要讲解下fragment1,因为它里面包含着另外两个viewpager。
3. 中间层的viewpager的布局实现
- 一个简单的tablayout配合viewpager使用,对tablayout的样式做了设定。
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<android.support.design.widget.TabLayout
android:id="@+id/tab_main"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#1e8ae8"
app:tabGravity="fill"
app:tabIndicatorColor="#fff"
app:tabIndicatorHeight="4dp"
app:tabMode="fixed"
app:tabSelectedTextColor="#fff"
app:tabTextColor="#97c8f4"
>
</android.support.design.widget.TabLayout>
<android.support.v4.view.ViewPager
android:id="@+id/vp_menu_pager"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
</android.support.v4.view.ViewPager>
</LinearLayout>
4. 中间层的viewpager的代码实现
public class Fragment1 extends Fragment {
private ViewPager mViewPager;
private MyTabFragmentPagerAdapter mMyTabFragmentPagerAdapter;
private List<Fragment> fragments;
private TabLayout.Tab one;
private TabLayout.Tab two;
private TabLayout.Tab three;
private TabLayout.Tab four;
private TabLayout mTabLayout;
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment1, container, false);
mTabLayout = (TabLayout) view.findViewById(R.id.tab_main);
mViewPager = (ViewPager) view.findViewById(R.id.vp_menu_pager);
initdata();
return view;
}
//初始化数据
private void initdata() {
fragments=new ArrayList<Fragment>();
fragments.add(new TabFragment1());
fragments.add(new TabFragment2());
fragments.add(new TabFragment3());
fragments.add(new TabFragment4());
mMyTabFragmentPagerAdapter = new MyTabFragmentPagerAdapter(getActivity().getSupportFragmentManager()
,fragments);
mViewPager.setOffscreenPageLimit(4);
mViewPager.setAdapter(mMyTabFragmentPagerAdapter);
//将TabLayout和ViewPager绑定在一起,使双方各自的改变都能直接影响另一方,解放了开发人员对双方变动事件的监听
mTabLayout.setupWithViewPager(mViewPager);
//指定Tab的位置
one = mTabLayout.getTabAt(0);
two = mTabLayout.getTabAt(1);
three = mTabLayout.getTabAt(2);
four = mTabLayout.getTabAt(3);
}
}
- 中间层的viewpager的FragmentPagerAdapter适配器
public class MyTabFragmentPagerAdapter extends FragmentPagerAdapter {
private String[] mTitles = new String[]{"推荐", "圆桌", "热门","收藏"};
private List<Fragment> fragments;
public MyTabFragmentPagerAdapter(FragmentManager fm,List<Fragment> fragments) {
super(fm);
this.fragments=fragments;
}
@Override
public Fragment getItem(int position) {
return fragments.get(position);
}
@Override
public int getCount() {
return mTitles.length;
}
//用来设置tab的标题
@Override
public CharSequence getPageTitle(int position) {
return mTitles[position];
}
}
5. 顶层的viewpager的实现
在布局只是在fragment中放入一个recycleview,而轮播的viewpager是作为头布局加入recycleview中的。
下面是头布局的代码
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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="wrap_content"
android:orientation="vertical">
<android.support.v4.view.ViewPager
android:id="@+id/vp_tab_headview"
android:layout_width="match_parent"
android:layout_height="180dp">
</android.support.v4.view.ViewPager>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:background="#fff">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_centerInParent="true">
//在布局中添加viewpagerindicator,通过自定义属性设置好外观
<com.viewpagerindicator.CirclePageIndicator
android:id="@+id/indicator"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="10dip"
app:fillColor="#f00"
app:pageColor="#e0e0e0"
app:radius="4dp"
app:strokeWidth="0dp"/>
</RelativeLayout>
</RelativeLayout>
</LinearLayout>
- 下面是TabFragment1 的逻辑代码
//省略viewpager的adapter,因为不重要
public class TabFragment1 extends Fragment {
private RecyclerView mRecyclerView;
private List<String> mDatas;
private ArrayList<ImageView> imageList;
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.tab_fragment1, container, false);
mRecyclerView = (RecyclerView) view.findViewById(R.id.recycle);
mRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity(), LinearLayoutManager.VERTICAL, false));
initdata();//初始化数据
mRecyclerView.setAdapter(new MyAdapter(mDatas));
return view;
}
private void initdata() {
//初始化recycleview的数据
mDatas = new ArrayList<String>();
for (int i = 0; i < 45; i++) {
mDatas.add("item" + i);
}
//初始化viewpager的数据
int[] imageResIDs = {R.drawable.a, R.drawable.b, R.drawable.c};
imageList = new ArrayList<ImageView>();
for (int i = 0; i < imageResIDs.length; i++) {
ImageView image = new ImageView(getActivity());
image.setBackgroundResource(imageResIDs[i]);
imageList.add(image);
}
}
class MyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private List<String> mDatas;
private static final int HEAD_VIEW = 0;//头布局
private static final int BODY_VIEW = 1;//内容布局
private MyPagerAdapter mPagerAdapter = new MyPagerAdapter();
//创建构造参数,用来接受数据集
public MyAdapter(List<String> datas) {
this.mDatas = datas;
}
//创建ViewHolder
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == HEAD_VIEW) {
View view = LayoutInflater.from(parent.getContext())
.inflate(R.layout.headview_recycleview, parent, false);
MyHeadViewHolder viewHolder = new MyHeadViewHolder(view);
return viewHolder;
}
if (viewType == BODY_VIEW) {
//加载布局文件
View view = LayoutInflater.from(parent.getContext())
.inflate(R.layout.item_recycle, parent, false);
MyBodyViewHolder viewHolder = new MyBodyViewHolder(view);
return viewHolder;
}
return null;
}
//绑定ViewHolder
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
//将数据填充到具体的view中
if (holder instanceof MyHeadViewHolder) {
((MyHeadViewHolder) holder).mViewPager.setAdapter(mPagerAdapter);
((MyHeadViewHolder) holder).indicator.onPageSelected(0);
((MyHeadViewHolder) holder).indicator.setViewPager(((MyHeadViewHolder) holder).mViewPager);
((MyHeadViewHolder) holder).indicator.setSnap(true);
}
if (holder instanceof MyBodyViewHolder) {
((MyBodyViewHolder) holder).tv.setText(mDatas.get(position-1));
}
}
@Override
public int getItemCount() {
return mDatas.size() + 1;
}
//如果是第一项,则加载头布局
@Override
public int getItemViewType(int position) {
if (position == 0) {
return HEAD_VIEW;
} else {
return BODY_VIEW;
}
}
}
//头布局的viewholder
class MyHeadViewHolder extends RecyclerView.ViewHolder {
ViewPager mViewPager;
CirclePageIndicator indicator; //定义indicator
public MyHeadViewHolder(View itemView) {
super(itemView);
mViewPager = (ViewPager) itemView.findViewById(R.id.vp_tab_headview);
indicator = (CirclePageIndicator) itemView.findViewById(R.id.indicator);
}
}
class MyBodyViewHolder extends RecyclerView.ViewHolder {
TextView tv;
public MyBodyViewHolder(View itemView) {
super(itemView);
tv = (TextView) itemView.findViewById(R.id.recycle_tv);
}
}
}
- ViewPager+Fragment配合使用中的问题
如图,切换的时候可能导致页面被销毁。
- 解决方案:防止频繁的销毁视图,可以setOffscreenPageLimit(2)或者重写PagerAdaper的destroyItem方法为空。
这里是项目地址。
参考
http://blog.csdn.net/never_cxb/article/details/50520270
http://www.open-open.com/lib/view/open1431174803882.html
http://www.imooc.com/article/2742