fragment　add或replace两种方式添加多个fragment

最新推荐文章于 2025-10-21 00:23:02 发布

原创最新推荐文章于 2025-10-21 00:23:02 发布 · 1.4k 阅读

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博客介绍了两种方式的生命周期情况。replace方式每次都会重新走生命周期，而add方式首次会走生命周期，第二次则不再重新走。

第一种方式replace，每次都会重新走生命周期

private ConcurrentHashMap<String, BaseFragment> fragments = new ConcurrentHashMap<>();
private FragmentManager fm;
private FragmentTransaction tx;
private String homePagerFragment = HomePagerFragment.class.getSimpleName();
private BaseFragment mCurrentFragment;

private void switchPages(String selectPageIndex) {
    BaseFragment baseFragment = fragments.get(selectPageIndex);
    if (baseFragment == null) {
        if (selectPageIndex.equals(homePagerFragment)) {
            baseFragment = new HomePagerFragment();
            fragments.put(homePagerFragment, baseFragment);
        } else if (selectPageIndex.equals(filePagerFragment)) {
            baseFragment = new FilePagerFragment();
            fragments.put(filePagerFragment, baseFragment);
        }
    }
    mCurrentFragment = baseFragment;
    fm = getSupportFragmentManager();
    tx = fm.beginTransaction();
    tx.replace(R.id.vp_content_fragment_pages, baseFragment);
    tx.addToBackStack(selectPageIndex);
    tx.commitAllowingStateLoss();
}

第二次方式add,首次会走生命周期，第二次不再重新走生命周期

private FragmentManager fm;
private FragmentTransaction transaction;
private Fragment mCurrentFragment;
public static String generalView = GeneralInformationFragment.class.getSimpleName();

private void switchPages(String selectPageIndex) {
    fm = getSupportFragmentManager();
    transaction = fm.beginTransaction();
    if (mCurrentFragment != null) {
        transaction.hide(mCurrentFragment);
    }
    Fragment fragmentByTag = fm.findFragmentByTag(selectPageIndex);
    if (fragmentByTag == null) {
        if (selectPageIndex.equals(generalView)) {
            fragmentByTag = new GeneralInformationFragment();
        } else if (selectPageIndex.equals(networkView)) {
            fragmentByTag = new NetworkFragment();
        } else if (selectPageIndex.equals(storageView)) {
            fragmentByTag = new StorageFragment();
        }
        transaction.add(R.id.fl_system_status_content, fragmentByTag, selectPageIndex);
    }
    mCurrentFragment = fragmentByTag;
    transaction.show(fragmentByTag);
    transaction.commit();
}