java - 如何将选项卡 fragment Activity 转换为没有选项卡的正常 Activity

Question

我有以下代码，它是一个带有 fragment 的选项卡布局。我想摆脱选项卡/寻呼机并仅保留 1 个 fragment (StickyQuestionDetailsFragment) 并让它显示 Activity 的完整宽度和高度。

我尝试从我的 Activity 中打开 fragment ，但出现转换异常。

public class QuestionDetails extends SherlockFragmentActivity implements ActionBar.TabListener {
    ViewPager mPager;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.question_details);

        PagerAdapter adapter = new FragmentStatePagerAdapter(getSupportFragmentManager()) {
            @Override
            public Fragment getItem(int position) {
                switch (position) {
                    case 1:
                        return new QuickReturnFragment();
                    case 0:
                        return new StickyQuestionDetailsFragment();
                }
                return null;
            }

            @Override
            public int getCount() {
                return 1;//2
            }

            @Override
            public CharSequence getPageTitle(int position) {
                switch (position) {
                    case 0:
                        return "Question";
                    case 1:
                        return "User";
                }
                return null;
            }
        };

        mPager = (ViewPager) findViewById(R.id.pager);
        mPager.setAdapter(adapter);
        mPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
            @Override
            public void onPageSelected(int position) {
                getActionBar().setSelectedNavigationItem(position);
            }
        });

        mPager.setPageMargin(getResources().getDimensionPixelSize(R.dimen.page_margin));

        getActionBar().setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

        for (int position = 0; position < adapter.getCount(); position++) {
            getActionBar().addTab(getActionBar().newTab()
                    .setText(adapter.getPageTitle(position))
                    .setTabListener(this));
        }

        getActionBar().setDisplayShowHomeEnabled(false);
        getActionBar().setDisplayShowTitleEnabled(false);
    }

    @Override
    public void onTabSelected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
        mPager.setCurrentItem(tab.getPosition());
    }

    @Override
    public void onTabUnselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
    }

    @Override
    public void onTabReselected(ActionBar.Tab tab, FragmentTransaction fragmentTransaction) {
    }
}

Answer 1

如果每个 Activity 只需要一个 Fragment，则可以使用此模式 ( source ):

public class QuestionDetails extends SherlockFragmentActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        // If not already added to the Fragment manager add it. If you don't do this a new Fragment will be added every time this method is called (Such as on orientation change)
        if(savedInstanceState == null)
            getSupportFragmentManager().beginTransaction().add(android.R.id.content, new StickyQuestionDetailsFragment()).commit();
    }
}