Question

我正在尝试在fragment中创建可滑动的标签。在viewpager中添加标签。但它给了我错误当actionBar.setHomeButtonEnabled（false）为空指针异常无法进行instastaite活动时。我尝试解决过去两天的问题但无法解决问题。请帮我解决它。请找我的Fragment类。

public class HomeFragment扩展了Fragment工具 ActionBar.TabListener {

View FaramentView;
private FragmentActivity context;

private ViewPager viewPager;
private TabsPagerAdapter mAdapter;
private ActionBar actionBar;
// Tab titles
private String[] tabs = { "Top Rated", "Games", "Movies" };


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
    FaramentView = inflater.inflate(R.layout.home_fragment, null, false); 

    return FaramentView;

}

@Override public void onAttach(Activity activity) {

    context = (FragmentActivity) activity;


    super.onAttach(activity);
}

@TargetApi(Build.VERSION_CODES.HONEYCOMB) @Override
public void onActivityCreated(Bundle savedInstanceState) 
{

    super.onActivityCreated(savedInstanceState);
    // Initilization
            viewPager = (ViewPager) FaramentView.findViewById(R.id.pager);
             actionBar = context.getActionBar();

            mAdapter = new TabsPagerAdapter(context.getSupportFragmentManager());

            viewPager.setAdapter(mAdapter);
            actionBar.setHomeButtonEnabled(false);
            actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);        

            // Adding Tabs
            for (String tab_name : tabs) {
                actionBar.addTab(actionBar.newTab().setText(tab_name)
                        .setTabListener(this));
            }

            /**
             * on swiping the viewpager make respective tab selected
             * */
            viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {

                @Override
                public void onPageSelected(int position) {
                    // on changing the page
                    // make respected tab selected
                    actionBar.setSelectedNavigationItem(position);
                }

                @Override
                public void onPageScrolled(int arg0, float arg1, int arg2) {
                }

                @Override
                public void onPageScrollStateChanged(int arg0) {
                }
            });
}

public LayoutInflater getSystemService(String layoutInflaterService) {
    // TODO Auto-generated method stub
    return null;
}

@Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
    // TODO Auto-generated method stub

}

@Override
public void onTabSelected(Tab tab, FragmentTransaction ft) {
    // TODO Auto-generated method stub

}

@Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
    // TODO Auto-generated method stub

}

}

Answer 1

在活动添加

下的Android清单文件中

android:theme="@android:style/Theme.Holo"

我想将此添加为评论，但由于声誉的数量，我无法做到。

actionBar.setHomeButtonEnabled将片段中的错误作为空指针异常

1 个答案: