//初始化默认显示的界面if(purchaserHomeFragment==null){purchaserHomeFragment=newPurchaserHomeFragment();addFragment(purchaserHomeFragment);showFragment(purchaserHomeFragment);}else{showFragment(purchaserHomeFragment);}//购物车界面if(purchaserCarFragment==null){purchaserCarFragment=newPurchaserCarFragment();//判断当前界面是否隐藏，如果隐藏就进行添加显示，false表示显示，true表示当前界面隐藏if(!purchaserCarFragment.isHidden()){addFragment(purchaserCarFragment);showFragment(purchaserCarFragment);}}else{if(purchaserCarFragment.isHidden()){showFragment(purchaserCarFragment);}}/**添加fragment**/publicvoidaddFragment(Fragmentfragment){FragmentTransactionft=this.getSupportFragmentManager().beginTransaction();ft.add(R.id.fl_content,fragment);ft.commit();}/**显示fragment**/publicvoidshowFragment(Fragmentfragment){FragmentTransactionft=this.getSupportFragmentManager().beginTransaction();//判断页面是否已经创建，如果已经创建，那么就隐藏掉if(purchaserHomeFragment!=null){ft.hide(purchaserHomeFragment);}if(purchaserTypeFragment!=null){ft.hide(purchaserTypeFragment);}if(purchaserOrderFragment!=null){ft.hide(purchaserOrderFragment);}if(purchaserCarFragment!=null){ft.hide(purchaserCarFragment);}ft.show(fragment);ft.commitAllowingStateLoss();}