xamarin.forms - Xamarin Forms ListView ItemsSource -


i'm trying use listview in xamarin forms, have list , have divide depending on day

var activitiesservices = new activitiesservices();         var activities = activitiesservices.getactivities();          var datatemplate = new datatemplate(typeof(textcell));         datatemplate.setbinding(textcell.textproperty, "subject");          var list = new observablecollection<activity>();         var list2 = new observablecollection<activity>();         var list3 = new observablecollection<activity>();         var list4 = new observablecollection<activity>();         var list5 = new observablecollection<activity>();         foreach (activity item in activities) {             var day = item.starttime.dayofweek;             switch ((int)day) {                 case 1:                     list.add(item);                     break;                 case 2:                     list2.add(item);                     break;                 case 3:                     list3.add(item);                     break;                 case 4:                     list4.add(item);                     break;                 case 5:                     list5.add(item);                     break;                 default:                     break;             }}

it goes till here when try fill main list view(define in xaml) give me error:

           if (list.count != 0) {             monday.itemssource = list;             monday.itemtemplate = datatemplate;         }         if (list2.count != 0) {             tuesday.itemssource = list2;             tuesday.itemtemplate = datatemplate;         }         if (list3.count != 0) {             wednesday.itemssource = list3;             wednesday.itemtemplate = datatemplate;         }         if (list5.count != 0) {             friday.itemssource = list5;             friday.itemtemplate = datatemplate;         }         if (list4.count != 0) {             thursday.itemssource = list4;             thursday.itemtemplate = datatemplate;         }

this error: system.nullreferenceexception: object reference not set instance of object.

you can try listview provided syncfusion

use in xaml. defines group header template

<syncfusion:sflistview x:name="listview">   <syncfusion:sflistview.groupheadertemplate>     <datatemplate>       <viewcell>         <viewcell.view>           <stacklayout backgroundcolor="#e4e4e4">             <label text="{binding key}"                    fontsize="22"                    fontattributes="bold"                    verticaloptions="center"                    horizontaloptions="start"                    margin="20,0,0,0" />           </stacklayout>         </viewcell.view>       </viewcell>     </datatemplate>   </syncfusion:sflistview.groupheadertemplate> </syncfusion:sflistview>

enter image description here

it supports grouping , seems suitable case.


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