我使用 viewpager 在我的 fragment 中有两个选项卡。当我转到选项卡 2(时钟)并单击选项卡 1(仪表板)时，我在两个选项卡中都有 API 休息调用我想刷新选项卡 1 我想再次调用 API 休息调用，但它没有刷新。请帮助我。 这是我的查看寻呼机代码:
public class TabSampleFragment extends Fragment {
TabLayout gs_tabLayout;
ViewPager gs_viewPager;
ViewPagerAdapter mViewPagerAdapter;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
final View view = inflater.inflate(R.layout.activity_frag_tabs, container, false);
gs_tabLayout = (TabLayout)view.findViewById(R.id.gs_tabLayout);
gs_viewPager = (ViewPager)view.findViewById(R.id.gs_viewPager);
mViewPagerAdapter = new ViewPagerAdapter(getChildFragmentManager());
mViewPagerAdapter.addFragments(new Progress(), "Dashboard");
mViewPagerAdapter.addFragments(new ClockInDetails(), "Clocking");
gs_viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
} @Override
public void onPageSelected(int position) {
mViewPagerAdapter.notifyDataSetChanged(); //this line will force all pages to be loaded fresh when changing between fragments
}
@Override
public void onPageScrollStateChanged(int state) {
}
});
gs_viewPager.setAdapter(mViewPagerAdapter);
gs_tabLayout.setupWithViewPager(gs_viewPager);
gs_tabLayout.setTabGravity(TabLayout.GRAVITY_FILL);
mViewPagerAdapter.notifyDataSetChanged();
return view;
}
}
这是我的适配器代码:单击时如何刷新仪表板选项卡， fragment 生命周期也不调用(单击选项卡时开始、暂停、恢复、停止)
public class ViewPagerAdapter extends FragmentStatePagerAdapter {
ArrayList<Fragment> fragments = new ArrayList<>();
ArrayList<String> tabTitles = new ArrayList<>();
public void addFragments(Fragment fragments, String titles){
Log.i("RR","on add-gragment");
this.fragments.add(fragments);
this.tabTitles.add(titles);
}
public ViewPagerAdapter(FragmentManager fm) {
super(fm);
}
@Override
public Fragment getItem(int position) {
return fragments.get(position);
}
@Override
public int getCount() {
return fragments.size();
}
@Override
public CharSequence getPageTitle(int position) {
return tabTitles.get(position);
}
}
这是我的仪表板代码。我在 oncreate 和 uservisiblehint 方法中使用字符串请求调用 REST API。如果我没有在 uservisiblehint 方法中调用 rest 调用它的工作，但如果我调用意味着它显示问题
enter code here
public class Progress extends Fragment {
ProgressBar gs_circularProgressBar;
public ProgressDialog mProgDialog;
ImageView gs_image_userProfileimage;
private TextView gs_text_username, gs_text_companyname, gs_text_completedTaskasValue, gs_text_assignedTaskasValue, gs_assignedTaskTextView, gs_text_totalDistanceValue, gs_totalDistanceTextView, gs_kmsLabel, gs_totalHoursTextView, gs_text_totalHoursasValue;
Typeface tf1, tf2, tf3, tf4;
Float gs_var_dist_travel;
String gs_var_userimage,gs_var_username,gs_var_companyname,gs_var_total_task,gs_var_complete_task,gs_var_timetaken,gs_var_roleid,gs_var_userid;
int gs_var_networkx=2;
public Progress() {
// Required empty public constructor
}
ProgressBar progressBar1;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.con_fragment_progress, container, false);
gs_circularProgressBar = (ProgressBar)view.findViewById (R.id.gs_circularProgressBar);
GS_User_Dashboard(gs_var_roleid,gs_var_userid);
return view;
}
private void GS_User_Dashboard( String gs_var_roleid, String gs_var_userid) {
StringRequest stringRequest = new StringRequest(Request.Method.GET, ServerUtils.Gs_User_Dashboard+"gs_userId="+gs_var_userid+"&gs_role="+gs_var_roleid,
new com.android.volley.Response.Listener<String>() {
@Override
public void onResponse(String response) {
}
},
new com.android.volley.Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError volleyError) {
//Dismissing the progress dialog
clearProgressDialog();
progressBar1.setVisibility(View.GONE);
//Showing toast
}
}) {
@Override
protected Map<String, String> getParams() throws AuthFailureError {
Map<String, String> params = new Hashtable<String, String>();
return params;
}
@Override
public Map<String, String> getHeaders() throws AuthFailureError {
Map<String, String> params = new HashMap<String, String>();
return params;
}
@Override protected void deliverResponse(String response) {
super.deliverResponse(response);
}
@Override public void deliverError(VolleyError error)
{
super.deliverError(error);
// progressBar1.setVisibility(View.GONE);
Log.e("deliverResponse", "getNetworkTimeMs : " + error);
}
};
RequestQueue requestQueue = Volley.newRequestQueue(getActivity());
//Adding request to the queue
requestQueue.add(stringRequest);
}
@Override
public void setUserVisibleHint(boolean isVisibleToUser) {
super.setUserVisibleHint(isVisibleToUser);
if (isVisibleToUser) {
// load data here and api call
GS_User_Dashboard(gs_var_roleid,gs_var_userid);
Log.i("EE","visible--progress");
}else{
}
}
}
最佳答案
View pager will by default load atleast 1 on the right and one on the left tab of current tab. It is done so, mostly because there is a point when u slide viewpager, when certain area of both tabs is visible. For those smooth transitions preloading is required.
但是由于您只有两个选项卡，所以这是一个问题，两个选项卡都是预加载的，当您转到第二个选项卡时不会刷新。
我建议您覆盖 setUserVisibleHint() 方法并在那里调用 api。
试试下面的代码:
@Override
public void setUserVisibleHint(boolean isVisibleToUser) {
super.setUserVisibleHint(isVisibleToUser);
if (isVisibleToUser) {
// load data here and api call
}else{
}
}
关于android - 如何在 Fragment 中使用 viewpager 刷新标签页，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/48823671/