How to sort listview by enum values in xamarin forms
You can sort the Xamarin.Forms ListView items based on the enum property values (multiple values) using the SortComparer.
XAML
Comparer added in Sort descriptor
<syncfusion:SfListView ItemsSource="{Binding PersonList}"
ItemSize="70" x:Name="listView">
<syncfusion:SfListView.DataSource>
<data:DataSource LiveDataUpdateMode="AllowDataShaping">
<data:DataSource.SortDescriptors>
<data:SortDescriptor PropertyName="AllergyType"
Comparer="{StaticResource comparer}"/>
</data:DataSource.SortDescriptors>
</data:DataSource>
</syncfusion:SfListView.DataSource>
</syncfusion:SfListView>
C#
Sort comparer that returns the item based on comparing the enum values.
public class CustomComparer : IComparer<object>
{
enum AllergyTypes
{
Drug,
Food,
Environmental
}
public int Compare(object x, object y)
{
if (x.GetType() == typeof(Allergy))
{
var xItem = (x as Allergy).AllergyType;
var yItem = (y as Allergy).AllergyType;
if (xItem.ToString() == AllergyTypes.Drug.ToString())
{
if (yItem.ToString() == AllergyTypes.Drug.ToString())
{
return 0; //Same Level
}
if (yItem.ToString() == AllergyTypes.Food.ToString())
{
return -1; //One Level Down
}
if (yItem.ToString() == AllergyTypes.Environmental.ToString())
{
return -2; //Two Level Down
}
}
if (xItem.ToString() == AllergyTypes.Food.ToString())
{
if (yItem.ToString() == AllergyTypes.Drug.ToString())
{
return 1; //One Level Up
}
if (yItem.ToString() == AllergyTypes.Food.ToString())
{
return 0; //Same Level
}
if (yItem.ToString() == AllergyTypes.Environmental.ToString())
{
return -1; //One Level Down
}
}
if (xItem.ToString() == AllergyTypes.Environmental.ToString())
{
if (yItem.ToString() == AllergyTypes.Drug.ToString())
{
return 2; //Two Level Up
}
if (yItem.ToString() == AllergyTypes.Food.ToString())
{
return 1; //One Level Up
}
if (yItem.ToString() == AllergyTypes.Environmental.ToString())
{
return 0; //Same Level
}
}
}
return 0;
}
}
