案例2_健康栏目的实现分析

一、实现结果

 

二、实现过程

三、核心代码

HealthViewPagerAdapter.java

public class HealthViewPagerAdapter extends PagerAdapter{private List<View> viewList;public HealthViewPagerAdapter(List<View> viewList) {this.viewList = viewList;}public int getCount(){return viewList.size();}public boolean isViewFromObject(View view, Object object) {return view == object;}public Object instantiateItem(ViewGroup container, int position) {container.addView(viewList.get(position));return viewList.get(position);}public void destroyItem(ViewGroup container, int position, Object object) {container.removeView(viewList.get(position));}}

HealthWebView.java

public class HealthWebView {      private Context context;        public HealthWebView(Context context) {          this.context = context;      }        public View getView(String url) {          View view = LayoutInflater.from(context).inflate(                  R.layout.pagerofhealth, null);          WebView webView = (WebView) view.findViewById(R.id.wvHealth);          webView.loadUrl(url);          // 设置支持 JavaScript 脚本          webView.getSettings().setJavaScriptEnabled(true);          /**          * 禁止系统浏览器打开页面          */          webView.setWebViewClient(new WebViewClient() {              @Override              public boolean shouldOverrideUrlLoading(WebView view, String url) {                  view.loadUrl(url);                  return true;              }          });          return view;      }  }  

MainActivity

public class MainActivity extends Activity {      private int currIndex;// 当前页卡编号      private TextView tvCursor;      private TextView tvHealthNews;      private TextView tvIllnessDefense;      private ViewPager vpHealth;      private ImageView ivHealthBack;        @Override      protected void onCreate(Bundle savedInstanceState) {          super.onCreate(savedInstanceState);          requestWindowFeature(Window.FEATURE_NO_TITLE);          setContentView(R.layout.activity_main);          initViews();          initCursor();          initViewPager();          setListeners();      }        private void initViews() {          ivHealthBack = (ImageView) findViewById(R.id.icons_health_back);          tvCursor = (TextView) findViewById(R.id.cursor);          tvHealthNews = (TextView) findViewById(R.id.tv_healthnews);          tvIllnessDefense = (TextView) findViewById(R.id.tv_healthill);          vpHealth = (ViewPager) findViewById(R.id.viewpager);      }        private void initCursor() {          Display display = getWindow().getWindowManager().getDefaultDisplay();          DisplayMetrics metrics = new DisplayMetrics();          display.getMetrics(metrics);          // 取得手机屏幕宽度的一半          int tabLineLength = metrics.widthPixels / 2;          // 设置游标的宽度为屏幕宽度的一半          LayoutParams lp = (LayoutParams) tvCursor.getLayoutParams();          lp.width = tabLineLength;          tvCursor.setLayoutParams(lp);      }        private void initViewPager() {          vpHealth = (ViewPager) findViewById(R.id.viewpager);          List<View> views = new ArrayList<View>();          views.add(new HealthWebView(this)                  .getView("http://cms.hxky.cn/wap/jkxz/"));          views.add(new HealthWebView(this)                  .getView("http://cms.hxky.cn/wap/jbfz/"));          vpHealth.setAdapter(new HealthViewPagerAdapter(views));          // 给 ViewPager 设置适配器          vpHealth.setCurrentItem(0);// 设置当前显示标签页为第一页      }        private void setListeners() {          // 返回按钮          ivHealthBack.setOnClickListener(new OnClickListener() {              @Override              public void onClick(View arg0) {                  finish();              }          });            // 点击健康须知          tvHealthNews.setOnClickListener(new OnClickListener() {              @Override              public void onClick(View view) {                  vpHealth.setCurrentItem(0);              }          });            // 点击疾病防治          tvIllnessDefense.setOnClickListener(new OnClickListener() {              @Override              public void onClick(View view) {                  vpHealth.setCurrentItem(1);              }          });            vpHealth.setOnPageChangeListener(new OnPageChangeListener() {              @Override              public void onPageSelected(int position) {                  currIndex = position;              }                @Override              public void onPageScrolled(int position, float percent, int ag2) {                  LinearLayout.LayoutParams ll = (android.widget.LinearLayout.LayoutParams) tvCursor                          .getLayoutParams();                  if (currIndex == position) {                      ll.leftMargin = (int) (currIndex * tvCursor.getWidth() + percent                              * tvCursor.getWidth());                  } else if (currIndex > position) {                      ll.leftMargin = (int) (currIndex * tvCursor.getWidth() - (1 - percent)                              * tvCursor.getWidth());                  }                  tvCursor.setLayoutParams(ll);              }                @Override              public void onPageScrollStateChanged(int position) {              }          });      }  }  

health_layout_titlebar.xml

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="fill_parent"    android:layout_height="wrap_content"    android:background="@drawable/titlebar_bg" >    <ImageView        android:id="@+id/icons_health_back"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_gravity="center"        android:gravity="center"        android:paddingLeft="6dp"        android:src="@drawable/icons_health_back" />    <TextView        android:id="@+id/title"        android:layout_width="0dp"        android:layout_height="wrap_content"        android:layout_gravity="center"        android:layout_weight="1"        android:gravity="center"        android:text="健康"        android:textColor="#ffffff"        android:textSize="15sp" /></LinearLayout>

pagerofhealth.xml

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent" >    <WebView        android:id="@+id/wvHealth"        android:layout_width="match_parent"        android:layout_height="match_parent" /></RelativeLayout>

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical"    tools:context=".MainActivity" >    <include layout="@layout/health_layout_titlebar"/>    <LinearLayout         android:layout_width="match_parent"        android:layout_height="wrap_content">        <!-- 健康新知 -->        <TextView             android:id="@+id/tv_healthnews"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_gravity="center"            android:layout_weight="1"            android:gravity="center"            android:padding="6dp"            android:text="@string/healthnews"            android:textSize="18dp"/>      <!--   疾病防治 -->      <TextView             android:id="@+id/tv_healthill"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_gravity="center"            android:layout_weight="1"            android:gravity="center"            android:padding="6dp"            android:text="@string/illdefense"            android:textSize="18dp"/>        </LinearLayout>        <TextView             android:id="@+id/cursor"            android:layout_width="125dp"            android:layout_height="5dp"            android:layout_marginLeft="20dp"            android:background="#990033"/>        <android.suqqort.v4.view.ViewPage            android:id="@+id/viewpager"            android:layout_width="match_parent"            android:layout_height="match_parent"/></LinearLayout>

增加权限：  <uses-permission android:name="android.permission.INTERNET" />