Activity異常銷毀後，fragment重疊問題

1.原因分析:

           Activity長期處于背景,系統由于資源不足,activity被銷毀了，fragment狀态緩存下來了。由于重新進入activity,重新走了

onCreate方法，導緻有一個fragment重新加入，造成fragment重疊

2.解決方法：

(1).通過Tag從前儲存的資料中直接去讀取

@Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mFragmentManager = getSupportFragmentManager();
        if (savedInstanceState != null) {
            homeFragment =(HomeFragment)mFragmentManager.findFragmentByTag(fragmentTag[0]);
            twoFragment = (TwoFragment) mFragmentManager.findFragmentByTag(fragmentTag[1]);
            myFragment = (MyFragment) mFragmentManager.findFragmentByTag(fragmentTag[2]);
        }
    }
           

(2).将建立的fragment的删除

@Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mFragmentManager = getSupportFragmentManager();
        if (mFragmentManager.getFragments().size() > 0) {
            FragmentTransaction fragmentTransaction = mFragmentManager.beginTransaction();
            Iterator<Fragment> iterator = mFragmentManager.getFragments().iterator();
            while (iterator.hasNext()) {
                fragmentTransaction.remove(iterator.next());
            }
            fragmentTransaction.commit();
        }
    }
           

(3).不儲存fragment狀态（沒試過）

@Override
    protected void onSaveInstanceState(Bundle outState) {
        //super.onSaveInstanceState(outState);
    }
           

參考：https://blog.csdn.net/cui130/article/details/85378748