如何创建片段

Question

我正在创建片段，为每个片段创建一个不同的类。现在我只测试了7个片段，这在使用应用程序时已经占用了太多的内存和空间。对于我的支持页面浏览器的应用程序，我需要400-500个片段，您可以在其中水平滑动它们。所有片段将具有相同的背景，相同的按钮，但只有不同的文本。所以我认为没有必要为每个人创建一个类，因为它们实际上是相同的。结论：是否有另一种方法来创建片段而不是为每个片段创建一个类？

这是我的代码（为了能够观察我目前管理片段的方式）：

public class MainActivity extends FragmentActivity  {

/**
 * The {@link android.support.v4.view.PagerAdapter} that will provide
 * fragments for each of the sections. We use a
 * {@link android.support.v4.app.FragmentPagerAdapter} derivative, which
 * will keep every loaded fragment in memory. If this becomes too memory
 * intensive, it may be best to switch to a
 * {@link android.support.v4.app.FragmentStatePagerAdapter}.
 */
SectionsPagerAdapter mSectionsPagerAdapter;

/**
 * The {@link ViewPager} that will host the section contents.
 */
ViewPager mViewPager;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // Set up the action bar.


    // Create the adapter that will return a fragment for each of the three
    // primary sections of the app.
    mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());

    // Set up the ViewPager with the sections adapter.
    mViewPager = (ViewPager) findViewById(R.id.pager);
    mViewPager.setAdapter(mSectionsPagerAdapter);

    // When swiping between different sections, select the corresponding
    // tab. We can also use ActionBar.Tab#select() to do this if we have
    // a reference to the Tab.
    mViewPager.setOnPageChangeListener(new ViewPager.SimpleOnPageChangeListener() {
        @Override
        public void onPageSelected(int position) {
        }        
    });

}


public class SectionsPagerAdapter extends FragmentPagerAdapter {

    public SectionsPagerAdapter(FragmentManager fm) {
        super(fm);
    }

    @Override
    public Fragment getItem(int position) {Fragment f = null;
    switch(position){
    case 0:
    {
    f = new DummySectionFragment();//YourFragment
    // set arguments here, if required
    Bundle args = new Bundle();
    f.setArguments(args);
    break;
    }
    case 1:
    {
        f = new Fragment2();//YourFragment
        // set arguments here, if required
        Bundle args = new Bundle();
        f.setArguments(args);
        break;
    }
    case 2:
    {
        f = new Fragment3();//YourFragment
        // set arguments here, if required
        Bundle args = new Bundle();
        f.setArguments(args);
        break;
    }
    case 3:
    {
        f = new Fragment4();//YourFragment
        // set arguments here, if required
        Bundle args = new Bundle();
        f.setArguments(args);
        break;
    }
    case 4:
    {
        f = new Fragment5();//YourFragment
        // set arguments here, if required
        Bundle args = new Bundle();
        f.setArguments(args);
        break;
    }
    case 5:
    {
        f = new Fragment6();//YourFragment
        // set arguments here, if required
        Bundle args = new Bundle();
        f.setArguments(args);
        break;
    }
    case 6:
    {
        f = new Fragment7();//YourFragment
        // set arguments here, if required
        Bundle args = new Bundle();
        f.setArguments(args);
        break;
    }

    default:
      throw new IllegalArgumentException("not this many fragments: " + position);
    }


    return f;
    }



    @Override
    public int getCount() {
        // Show 3 total pages.
        return 7;
    }


}

/**
 * A dummy fragment representing a section of the app, but that simply
 * displays dummy text.
 */
public static class DummySectionFragment extends Fragment {
    /**
     * The fragment argument representing the section number for this
     * fragment.
     */
    public static final String ARG_SECTION_NUMBER = "section_number";

    public DummySectionFragment() {
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_main_dummy, container, false);
        TextView dummyTextView = (TextView) rootView.findViewById(R.id.section_label);
        dummyTextView.setText(Integer.toString(getArguments().getInt(ARG_SECTION_NUMBER)));
        return rootView;
    }


}  public static class Fragment2 extends Fragment {
    /**
     * The fragment argument representing the section number for this
     * fragment.
     */
    public static final String ARG_SECTION_NUMBER = "section_number";

    public Fragment2() {
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment2, container, false);
        TextView dummyTextView = (TextView) rootView.findViewById(R.id.section_label);
        dummyTextView.setText(Integer.toString(getArguments().getInt(ARG_SECTION_NUMBER)));
        return rootView;
    }
}  public static class Fragment3 extends Fragment {
    /**
     * The fragment argument representing the section number for this
     * fragment.
     */
    public static final String ARG_SECTION_NUMBER = "section_number";

    public Fragment3() {
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment3, container, false);
        TextView dummyTextView = (TextView) rootView.findViewById(R.id.section_label);
        dummyTextView.setText(Integer.toString(getArguments().getInt(ARG_SECTION_NUMBER)));
        return rootView;
    }
}  public static class Fragment4 extends Fragment {
    /**
     * The fragment argument representing the section number for this
     * fragment.
     */
    public static final String ARG_SECTION_NUMBER = "section_number";

    public Fragment4() {
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment4, container, false);
        TextView dummyTextView = (TextView) rootView.findViewById(R.id.section_label);
        dummyTextView.setText(Integer.toString(getArguments().getInt(ARG_SECTION_NUMBER)));
        return rootView;
    }
}  public static class Fragment5 extends Fragment {
    /**
     * The fragment argument representing the section number for this
     * fragment.
     */
    public static final String ARG_SECTION_NUMBER = "section_number";

    public Fragment5() {
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment5, container, false);
        TextView dummyTextView = (TextView) rootView.findViewById(R.id.section_label);
        dummyTextView.setText(Integer.toString(getArguments().getInt(ARG_SECTION_NUMBER)));
        return rootView;
    } }  
    public static class Fragment6 extends Fragment {
        /**
         * The fragment argument representing the section number for this
         * fragment.
         */
        public static final String ARG_SECTION_NUMBER = "section_number";

        public Fragment6() {
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment6, container, false);
            TextView dummyTextView = (TextView) rootView.findViewById(R.id.section_label);
            dummyTextView.setText(Integer.toString(getArguments().getInt(ARG_SECTION_NUMBER)));
            return rootView;
        }   } 
        public static class Fragment7 extends Fragment {
            /**
             * The fragment argument representing the section number for this
             * fragment.
             */
            public static final String ARG_SECTION_NUMBER = "section_number";

            public Fragment7() {
            }

            @Override
            public View onCreateView(LayoutInflater inflater, ViewGroup container,
                    Bundle savedInstanceState) {
                View rootView = inflater.inflate(R.layout.fragment7, container, false);
                TextView dummyTextView = (TextView) rootView.findViewById(R.id.section_label);
                dummyTextView.setText(Integer.toString(getArguments().getInt(ARG_SECTION_NUMBER)));
                return rootView;    }


}
}

Answer 1

是只创建一个片段类并在从viewpageradapter返回片段时传递参数，并在片段中根据您传递的参数显示文本