如何在片段切换语句中显示 activity

Question

我构建了一个使用选项卡进行导航的 Android 应用程序。我为大部分应用程序使用片段，但我需要显示一个 activity。我如何在情况 2 中显示 activity。下面是我目前拥有的代码，我知道它是 returns 一个片段，但我如何启用两者的使用？

public class SectionsPagerAdapter extends FragmentPagerAdapter {

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

        @Override
        public Fragment getItem(int position) {
            // getItem is called to instantiate the fragment for the given page.
            // Return a PlaceholderFragment (defined as a static inner class below).
            System.out.println("current position = " + position);
            Fragment fragment = null;
            switch(position){

                case 0:
                    return new diaryFragment();
                case 1:
                    return new newEntryFragment();
                case 2:
                    return new Calendarnew();
        }


          return null;

        }

Answer 1

private void displayView(int position) {
        // update the main content by replacing fragments
        Fragment fragment = null;
        switch (position) {
        case 0:

            fragment = new diaryFragment();

            break;
        case 1:

            fragment = new newEntryFragment();

        case 2:

            fragment = new Calendarnew();
            break;

        default:
            break;
        }

        if (fragment != null) {
            FragmentManager fragmentManager = getFragmentManager();
            fragmentManager.beginTransaction()
                    .replace(R.id.frame_container, fragment).commit();


        } else {
            // error in creating fragment
            Log.e("MainActivity", "Error in creating fragment");
        }

Answer 2

您好，我实际上并不知道您在做什么，但请尝试阅读这篇文章，也许它能以某种方式解决您的问题。

如何在片段切换语句中显示 activity

How to i display activity in fragment switch statement

android

switch-statement

android-fragments

android-activity