ViewPager+Fragment+广播来实现一个滑动页面切换_html/css_WEB-ITnose
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2022-05-31 14:08:20
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要实现这样一个页面,上面的好说,下面的是一个滑动视图,我们想到的是用viewpager来实现,但是这个有一个问题,按照平时的写法,我们会写5个Activity放到viewpager里面去,这自然是可以实现的。但是这里有一个问题,一进来,在主界面manager.startActivity(id, intent).getDecorView();来取得view加到viewpager里,这样一启动,五个子界面都同时启动,都去加载数据,会导致很卡,也浪费了资源,我们想法是,默认只加载第一个页面,滑到第二个才开始加载第二个的数据,但是通过监听事件发现,一开始启动,五个Activity的oncreate方法都运行了。再滑动切换,是没有任何监听或者实现方法得到调用的。
每滑动一下,就发送广播,通知子界面去更新。但是是不是每次更新就有他自己控制了
这里后来想到了另外一个方法:我们用viewpager+5个Fragment+广播机制去通知他更新。
在主界面我们可以这样写。
/** * 初始化PageViewer */ Listlist; FragmentPagerAdapter myPagerAdapter; FragmentManager SupportfragmentManager = getSupportFragmentManager(); private void initPagerViewer(){ Label1AllOrder lable1 = new Label1AllOrder(); Label2WinPrizeOrder lable2 = new Label2WinPrizeOrder(); Label3WaitForLotteryOrder lable3 = new Label3WaitForLotteryOrder(); Label4ZhuiHaoOrder lable4 = new Label4ZhuiHaoOrder(); Label5BuyTogetherOrder lable5 = new Label5BuyTogetherOrder(); list = new ArrayList (); list.add(lable1); list.add(lable2); list.add(lable3); list.add(lable4); list.add(lable5); myPagerAdapter = new MyPagerAdapter(SupportfragmentManager); view_pager.setAdapter(myPagerAdapter); view_pager.setOnPageChangeListener(new MyOnPageChangeListener()); } /** * Pager适配器 */ public class MyPagerAdapter extends FragmentPagerAdapter { public MyPagerAdapter(FragmentManager fm) { super(fm); } @Override public Fragment getItem(int arg0) { return list.get(arg0); } @Override public int getCount() { return list.size(); } /*@Override public Object instantiateItem(View arg0, int arg1) { //ViewPager pViewPager = ((ViewPager) arg0); //pViewPager.addView(list.get(arg1).getView()); return list.get(arg1); } @Override public void destroyItem(ViewGroup container, int position, Object object) { //ViewPager pViewPager = ((ViewPager) container); //pViewPager.removeView(list.get(position).getView()); }*/ } private void sendBroadcastDoRefreshByCurrentIndex(){ switch (currentIndex) { case 0: sendBroadcastDoRefresh("action.Label1AllOrder"); break; case 1: sendBroadcastDoRefresh("action.Label2WinPrizeOrder"); break; case 2: sendBroadcastDoRefresh("action.Label3WaitForLotteryOrder"); break; case 3: sendBroadcastDoRefresh("action.Label4ZhuiHaoOrder"); break; case 4: sendBroadcastDoRefresh("action.Label5BuyTogetherOrder"); break; default: break; } } Intent broadCastIntent = new Intent(); // 广播通知 private void sendBroadcastDoRefresh(String action){ broadCastIntent.setAction(action); sendBroadcast(broadCastIntent); } /** * 页卡切换监听 */ private int currentIndex = 0; public class MyOnPageChangeListener implements OnPageChangeListener { @Override public void onPageSelected(int index) { currentIndex = index; System.out.println("-onPageSelected--------" + index); initViewPagePoint(index); switch (index) { case 0: sendBroadcastDoRefresh("action.Label1AllOrder"); view_pager_tip.setText("全部订单"); break; case 1: sendBroadcastDoRefresh("action.Label2WinPrizeOrder"); view_pager_tip.setText("中奖订单"); break; case 2: sendBroadcastDoRefresh("action.Label3WaitForLotteryOrder"); view_pager_tip.setText("待开奖订单"); break; case 3: sendBroadcastDoRefresh("action.Label4ZhuiHaoOrder"); view_pager_tip.setText("追号订单"); break; case 4: sendBroadcastDoRefresh("action.Label5BuyTogetherOrder"); view_pager_tip.setText("合买订单"); break; default: break; } } @Override public void onPageScrollStateChanged(int arg0) { } @Override public void onPageScrolled(int arg0, float arg1, int arg2) { } }
每滑动一下,就发送广播,通知子界面去更新。但是是不是每次更新就有他自己控制了
在五个子Fragment我们可以这样写:其实这里五个是相似了。我就贴一个的代码
public class Label2WinPrizeOrder extends Fragment implements OnClickListener { Activity activity = Label2WinPrizeOrder.this.getActivity(); @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); LayoutInflater inflater = getActivity().getLayoutInflater(); mainView = inflater.inflate(R.layout.my_lottery_user_center_label2_win_prize, (ViewGroup)getActivity().findViewById(R.id.my_lottery_user_center_viewpage), false); initUI(); initNoDataUI(); //注册刷新广播 IntentFilter intentFilter = new IntentFilter(); intentFilter.addAction("action.Label2WinPrizeOrder"); getActivity().registerReceiver(mRefreshBroadcastReceiver, intentFilter); } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { ViewGroup p = (ViewGroup) mainView.getParent(); if(p!=null){ p.removeAllViewsInLayout(); } return mainView; } @Override public void onActivityCreated(Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); } // broadcast receiver private BroadcastReceiver mRefreshBroadcastReceiver = new BroadcastReceiver() { @Override public void onReceive(Context context, Intent intent) { String action = intent.getAction(); if (action.equals("action.Label2WinPrizeOrder")) { System.out.println("---------------action.Label2WinPrizeOrder"); if (AutoUpdate.isNetworkAvailable(activity)) { if(canLoadAgain){ loadingRelativelayout.setVisibility(View.VISIBLE); noDataLinearlayout.setVisibility(View.GONE); hasDataLinearlayout.setVisibility(View.GONE); updateInitLotteryInfo(); page = 0; mListView.mEndRootView.setVisibility(View.GONE); mListView.setAutoLoadMore(true); mListView.setCanRefresh(true); new getDataTask().execute(1); } } setK3ballVisible(); } } }; //初设化彩种信息 private void updateInitLotteryInfo(){ if(MyLotterActivity.labelsListData != null && MyLotterActivity.labelsListData.size() >= 2){ MyLotteryLabelBean bean = MyLotterActivity.labelsListData.get(1); if(FunctionUtil.strNotNull(bean.getLottery_type_index())){ if("308".equals(bean.getLottery_type_index())){ lottery_type_index = 308; }else if("309".equals(bean.getLottery_type_index())){ lottery_type_index = 309; }else if("310".equals(bean.getLottery_type_index())){ lottery_type_index = 310; } } if(FunctionUtil.strNotNull(bean.getTitle())){ title = bean.getTitle(); } tipTextview.setText(title); } } private void initUI() { activity = getActivity(); loadingRelativelayout = (LinearLayout) mainView.findViewById(R.id.my_lottery_user_center_label2_loading_rel); loadAgainRelativelayout = (RelativeLayout) mainView.findViewById(R.id.my_lottery_user_center_label2_load_again_rel); hasDataLinearlayout = (LinearLayout) mainView.findViewById(R.id.my_lottery_user_center_label2_has_data_linear); noDataLinearlayout = (LinearLayout) mainView.findViewById(R.id.my_lottery_user_center_label2_no_data_linear);
}
这样。我们每次滑动一次就能在五个子类,得到一次广播通知。就让他去加载数据,当第二次在滑动到那个,他依然可以收到广播,至于要不要再去刷新数据,就看你怎么控制了。