Android FragmentManager管理器 封裝方法

private void setFragment(int index) {
        //獲取Fragment管理器
        FragmentManager mFragmentManager = getSupportFragmentManager();
        //開啓事務
        FragmentTransaction mTransaction = mFragmentManager.beginTransaction();
        //隱藏所有Fragment
        hideFragments(mTransaction);
        switch (index) {
            default:
                break;
            case 0:
                //顯示對應Fragment
                if (fragmentA == null) {
                    fragmentA = new FragmentA();
                    mTransaction.add(R.id.ll_fragment, fragmentA,
                            "fragment_A");
                } else {
                    mTransaction.show(fragmentA);
                }
                break;
            case 1:
                if (fragmentB == null) {
                    fragmentB = new FragmentB();
                    mTransaction.add(R.id.ll_fragment, fragmentB,
                            "fragment_B");
                } else {
                    mTransaction.show(fragmentB);
                }
                break;
            case 2:
                if (fragmentC == null) {
                    fragmentC = new FragmentC();
                    mTransaction.add(R.id.ll_fragment, fragmentC,
                            "fragment_C");
                } else {
                    mTransaction.show(fragmentC);
                }
                break;
        }
        //提交事務
        mTransaction.commit();
    }

    private void hideFragments(FragmentTransaction transaction) {
        if (fragmentA != null) {
            //隱藏Fragment
            transaction.hide(fragmentA);
        }
        if (fragmentB != null) {
            transaction.hide(fragmentB);
        }
        if (fragmentC != null) {
            transaction.hide(fragmentC);
        }
    }

封裝的方法,在點擊事件調用setFragment(), 傳入下標,在對應的case下,處理就可以