百思不得其解为什么会出现这种类转换错误。也试过不少方法，实在不得其所。
请大触们不吝赐教，谢谢~
运行报错：
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.wolfgy.news.newsclient, PID: 1109
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.wolfgy.news.newsclient/com.wolfgy.news.newsclient.MainActivity}: java.lang.ClassCastException: android.widget.FrameLayout cannot be cast to android.support.v4.view.ViewPager
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2219)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2269)
at android.app.ActivityThread.access$800(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5045)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.ClassCastException: android.widget.FrameLayout cannot be cast to android.support.v4.view.ViewPager
at com.wolfgy.news.newsclient.MainActivity.initView(MainActivity.java:84)
at com.wolfgy.news.newsclient.MainActivity.onCreate(MainActivity.java:52)
at android.app.Activity.performCreate(Activity.java:5231)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1104)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2163)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2269)
at android.app.ActivityThread.access$800(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5045)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
at dalvik.system.NativeStart.main(Native Method)
备注：这里说的MainActivity.java:84指的是viewPager = (ViewPager)findViewById(R.id.main_viewPager); 这一行。
MainActivity代码如下
public class MainActivity extends FragmentActivity {
FragmentTabHost fragmentTabHost;
SlidingMenu slidingMenu;
List<Fragment> list = new ArrayList<Fragment>();
String[] titles={"新闻中心" ,"博客频道","体育频道","科技频道","财经频道","视频","影音娱乐","读书频道","女性频道","男性频道","军事频道","汽车新闻","教育频道","房地产","游戏频道","星座频道"};
Class[] fragmentArray = {HeadLineFragment.class, BlogFragment.class, SportsFragment.class, ScientistFragment.class,EconomicsFragment.class, VideoFragment.class, EntertainmentFragment.class, ReadingFragment.class, FemaleFragment.class, MaleFragment.class, MilitaryFragment.class,CarsFragment.class, EducationFragment.class, HouseFragment.class, GamesFragment.class,ConstellationFragment.class};
ViewPager viewPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.activity_main);
initView();
}
private void initView(){
fragmentTabHost = (FragmentTabHost)findViewById(R.id.main_fragmentTabHost);
fragmentTabHost.setup(this,getSupportFragmentManager(),R.id.main_viewPager);
int count = titles.length;
for (int i = 0; i < count; i++) {
TabHost.TabSpec tabSpec = fragmentTabHost.newTabSpec(titles[i]).setIndicator(getTabItemView(i));
fragmentTabHost.addTab(tabSpec,fragmentArray[i],null);
fragmentTabHost.setTag(i);
}
fragmentTabHost.setOnTabChangedListener(new TabHost.OnTabChangeListener() {
@Override
public void onTabChanged(String s) {
int position = fragmentTabHost.getCurrentTab();
viewPager.setCurrentItem(position);
}
});
//初始化ViewPager
viewPager = (ViewPager)findViewById(R.id.main_viewPager);
initPage();
viewPager.setAdapter(new MainActivityFragmentPagerAdapter(getSupportFragmentManager()));
viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener(){
@Override
public void onPageSelected(int position) {
fragmentTabHost.setCurrentTab(position);
}
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
@Override
public void onPageScrollStateChanged(int state) {
}
});
}
/**
* 初始化Fragment
*/
private void initPage(){
HeadLineFragment headLine = new HeadLineFragment();
BlogFragment blog = new BlogFragment();
SportsFragment sports = new SportsFragment();
ScientistFragment scientistFragment = new ScientistFragment();
EconomicsFragment economicsFragment = new EconomicsFragment();
VideoFragment videoFragment = new VideoFragment();
EntertainmentFragment entertainmentFragment = new EntertainmentFragment();
ReadingFragment readingFragment = new ReadingFragment();
FemaleFragment femaleFragment = new FemaleFragment();
MaleFragment maleFragment = new MaleFragment();
MilitaryFragment militaryFragment = new MilitaryFragment();
CarsFragment carsFragment = new CarsFragment();
EducationFragment educationFragment = new EducationFragment();
HouseFragment houseFragment = new HouseFragment();
GamesFragment gamesFragment = new GamesFragment();
ConstellationFragment constellationFragment = new ConstellationFragment();
list.add(headLine);
list.add(blog);
list.add(sports);
list.add(scientistFragment);
list.add(economicsFragment);
list.add(videoFragment);
list.add(entertainmentFragment);
list.add(readingFragment);
list.add(femaleFragment);
list.add(maleFragment);
list.add(militaryFragment);
list.add(carsFragment);
list.add(educationFragment);
list.add(houseFragment);
list.add(gamesFragment);
list.add(constellationFragment);
}
private View getTabItemView(int i){
View view = LayoutInflater.from(MainActivity.this).inflate(R.layout.fragment_tabhost_content_main,null);
TextView tv = (TextView) view.findViewById(R.id.tabhost_text);
tv.setText(titles[i]);
return view;
}
private class MainActivityFragmentPagerAdapter extends FragmentPagerAdapter{
public MainActivityFragmentPagerAdapter(FragmentManager fm){
super(fm);
}
@Override
public Fragment getItem(int position) {
return list.get(position);
}
@Override
public int getCount() {
return list.size();
}
}
}
activity_main.xml内容如下：
<?xml version="1.0" encoding="utf-8"?>
<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:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:orientation="vertical"
tools:context="com.wolfgy.news.newsclient.MainActivity">
<android.support.v4.app.FragmentTabHost
android:id="@+id/main_fragmentTabHost"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</android.support.v4.app.FragmentTabHost>
<android.support.v4.view.ViewPager
android:id="@+id/main_viewPager"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1" />
</LinearLayout>
