Mixing
Xamarin Forms not updating ListView
my PropertyChanged event is not updatin my listview in xamarin.
Could someone help me with that?
The Method RefreshListView is triggered when the searchbar text has changed.
My Viewmodel:
public class LebensmittelViewModel : INotifyPropertyChanged
{
private ObservableCollection<Lebensmittel> lebensmittelList = new ObservableCollection<Lebensmittel>();
public List<Lebensmittel> normalLebensmittelList = new List<Lebensmittel>();
public event PropertyChangedEventHandler PropertyChanged;
public LebensmittelViewModel()
{
normalLebensmittelList = App.LebensmittelDatabase.getAllLebensmittel();
}
public void RefreshListView(string searchBarText)
{
LebensmittelList = addItemInCollection(searchBarText);
}
public ObservableCollection<Lebensmittel> addItemInCollection(string searchBarText)
{
if (searchBarText != null)
{
foreach (var item in normalLebensmittelList)
{
if (item.Name.Contains(searchBarText) || item.Name.Contains(searchBarText.First().ToString().ToUpper()))
{
LebensmittelList.Add(item);
};
}
}
return LebensmittelList;
}
public void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
public ObservableCollection<Lebensmittel> LebensmittelList
{
get
{
return lebensmittelList;
}
set
{
lebensmittelList = value;
OnPropertyChanged("LebensmittelList");
}
}
}
Einkaufsliste.xaml
<ContentPage.Content>
<StackLayout Spacing="10" Padding="10">
<SearchBar x:Name="searchBar" Text="{Binding searchBarText}" Placeholder="Lebensmittel suchen..." VerticalOptions="StartAndExpand">
<SearchBar.Behaviors>
<behavior:TextChangedBehavior/>
</SearchBar.Behaviors>
</SearchBar>
<ListView x:Name="listView" ItemsSource="{Binding LebensmittelList}" HasUnevenRows="True">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout VerticalOptions="FillAndExpand" Orientation="Horizontal" Padding="10">
<Label Text="{Binding Name}" YAlign="Center" Font="Large"/>
<ia:Checkbox HorizontalOptions="EndAndExpand"/>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
</ContentPage.Content>
Einkaufsliste.xaml.cs
public Einkaufsliste ()
{
InitializeComponent ();
BindingContext = new LebensmittelViewModel();
}
I think everything should be okay but it's not working.
Hope someone could help me with this,
thanks
Edit for Tom:
public void RefreshListView(string searchBarText)
{
addItemInCollection(searchBarText);
}
public void addItemInCollection(string searchBarText)
{
if (searchBarText != null)
{
foreach (var item in normalLebensmittelList)
{
if (item.Name.Contains(searchBarText) || item.Name.Contains(searchBarText.First().ToString().ToUpper()))
{
AddItemToList(item);
};
}
}
}
private void AddItemToList(Lebensmittel item)
{
lebensmittelList.Add(item);
LebensmittelList = lebensmittelList;
}
c# listview xamarin xamarin.forms
asked Nov 20 '18 at 16:57
Marvin LMarvin L
54
add a comment |
my PropertyChanged event is not updatin my listview in xamarin.
Could someone help me with that?
The Method RefreshListView is triggered when the searchbar text has changed.
My Viewmodel:
public class LebensmittelViewModel : INotifyPropertyChanged
{
private ObservableCollection<Lebensmittel> lebensmittelList = new ObservableCollection<Lebensmittel>();
public List<Lebensmittel> normalLebensmittelList = new List<Lebensmittel>();
public event PropertyChangedEventHandler PropertyChanged;
public LebensmittelViewModel()
{
normalLebensmittelList = App.LebensmittelDatabase.getAllLebensmittel();
}
public void RefreshListView(string searchBarText)
{
LebensmittelList = addItemInCollection(searchBarText);
}
public ObservableCollection<Lebensmittel> addItemInCollection(string searchBarText)
{
if (searchBarText != null)
{
foreach (var item in normalLebensmittelList)
{
if (item.Name.Contains(searchBarText) || item.Name.Contains(searchBarText.First().ToString().ToUpper()))
{
LebensmittelList.Add(item);
};
}
}
return LebensmittelList;
}
public void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
public ObservableCollection<Lebensmittel> LebensmittelList
{
get
{
return lebensmittelList;
}
set
{
lebensmittelList = value;
OnPropertyChanged("LebensmittelList");
}
}
}
Einkaufsliste.xaml
<ContentPage.Content>
<StackLayout Spacing="10" Padding="10">
<SearchBar x:Name="searchBar" Text="{Binding searchBarText}" Placeholder="Lebensmittel suchen..." VerticalOptions="StartAndExpand">
<SearchBar.Behaviors>
<behavior:TextChangedBehavior/>
</SearchBar.Behaviors>
</SearchBar>
<ListView x:Name="listView" ItemsSource="{Binding LebensmittelList}" HasUnevenRows="True">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout VerticalOptions="FillAndExpand" Orientation="Horizontal" Padding="10">
<Label Text="{Binding Name}" YAlign="Center" Font="Large"/>
<ia:Checkbox HorizontalOptions="EndAndExpand"/>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
</ContentPage.Content>
Einkaufsliste.xaml.cs
public Einkaufsliste ()
{
InitializeComponent ();
BindingContext = new LebensmittelViewModel();
}
I think everything should be okay but it's not working.
Hope someone could help me with this,
thanks
Edit for Tom:
public void RefreshListView(string searchBarText)
{
addItemInCollection(searchBarText);
}
public void addItemInCollection(string searchBarText)
{
if (searchBarText != null)
{
foreach (var item in normalLebensmittelList)
{
if (item.Name.Contains(searchBarText) || item.Name.Contains(searchBarText.First().ToString().ToUpper()))
{
AddItemToList(item);
};
}
}
}
private void AddItemToList(Lebensmittel item)
{
lebensmittelList.Add(item);
LebensmittelList = lebensmittelList;
}
c# listview xamarin xamarin.forms
asked Nov 20 '18 at 16:57
Marvin LMarvin L
54
add a comment |
my PropertyChanged event is not updatin my listview in xamarin.
Could someone help me with that?
The Method RefreshListView is triggered when the searchbar text has changed.
My Viewmodel:
public class LebensmittelViewModel : INotifyPropertyChanged
{
private ObservableCollection<Lebensmittel> lebensmittelList = new ObservableCollection<Lebensmittel>();
public List<Lebensmittel> normalLebensmittelList = new List<Lebensmittel>();
public event PropertyChangedEventHandler PropertyChanged;
public LebensmittelViewModel()
{
normalLebensmittelList = App.LebensmittelDatabase.getAllLebensmittel();
}
public void RefreshListView(string searchBarText)
{
LebensmittelList = addItemInCollection(searchBarText);
}
public ObservableCollection<Lebensmittel> addItemInCollection(string searchBarText)
{
if (searchBarText != null)
{
foreach (var item in normalLebensmittelList)
{
if (item.Name.Contains(searchBarText) || item.Name.Contains(searchBarText.First().ToString().ToUpper()))
{
LebensmittelList.Add(item);
};
}
}
return LebensmittelList;
}
public void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
public ObservableCollection<Lebensmittel> LebensmittelList
{
get
{
return lebensmittelList;
}
set
{
lebensmittelList = value;
OnPropertyChanged("LebensmittelList");
}
}
}
Einkaufsliste.xaml
<ContentPage.Content>
<StackLayout Spacing="10" Padding="10">
<SearchBar x:Name="searchBar" Text="{Binding searchBarText}" Placeholder="Lebensmittel suchen..." VerticalOptions="StartAndExpand">
<SearchBar.Behaviors>
<behavior:TextChangedBehavior/>
</SearchBar.Behaviors>
</SearchBar>
<ListView x:Name="listView" ItemsSource="{Binding LebensmittelList}" HasUnevenRows="True">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout VerticalOptions="FillAndExpand" Orientation="Horizontal" Padding="10">
<Label Text="{Binding Name}" YAlign="Center" Font="Large"/>
<ia:Checkbox HorizontalOptions="EndAndExpand"/>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
</ContentPage.Content>
Einkaufsliste.xaml.cs
public Einkaufsliste ()
{
InitializeComponent ();
BindingContext = new LebensmittelViewModel();
}
I think everything should be okay but it's not working.
Hope someone could help me with this,
thanks
Edit for Tom:
public void RefreshListView(string searchBarText)
{
addItemInCollection(searchBarText);
}
public void addItemInCollection(string searchBarText)
{
if (searchBarText != null)
{
foreach (var item in normalLebensmittelList)
{
if (item.Name.Contains(searchBarText) || item.Name.Contains(searchBarText.First().ToString().ToUpper()))
{
AddItemToList(item);
};
}
}
}
private void AddItemToList(Lebensmittel item)
{
lebensmittelList.Add(item);
LebensmittelList = lebensmittelList;
}
c# listview xamarin xamarin.forms
asked Nov 20 '18 at 16:57
Marvin LMarvin L
54
my PropertyChanged event is not updatin my listview in xamarin.
Could someone help me with that?
The Method RefreshListView is triggered when the searchbar text has changed.
My Viewmodel:
public class LebensmittelViewModel : INotifyPropertyChanged
{
private ObservableCollection<Lebensmittel> lebensmittelList = new ObservableCollection<Lebensmittel>();
public List<Lebensmittel> normalLebensmittelList = new List<Lebensmittel>();
public event PropertyChangedEventHandler PropertyChanged;
public LebensmittelViewModel()
{
normalLebensmittelList = App.LebensmittelDatabase.getAllLebensmittel();
}
public void RefreshListView(string searchBarText)
{
LebensmittelList = addItemInCollection(searchBarText);
}
public ObservableCollection<Lebensmittel> addItemInCollection(string searchBarText)
{
if (searchBarText != null)
{
foreach (var item in normalLebensmittelList)
{
if (item.Name.Contains(searchBarText) || item.Name.Contains(searchBarText.First().ToString().ToUpper()))
{
LebensmittelList.Add(item);
};
}
}
return LebensmittelList;
}
public void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
public ObservableCollection<Lebensmittel> LebensmittelList
{
get
{
return lebensmittelList;
}
set
{
lebensmittelList = value;
OnPropertyChanged("LebensmittelList");
}
}
}
Einkaufsliste.xaml
<ContentPage.Content>
<StackLayout Spacing="10" Padding="10">
<SearchBar x:Name="searchBar" Text="{Binding searchBarText}" Placeholder="Lebensmittel suchen..." VerticalOptions="StartAndExpand">
<SearchBar.Behaviors>
<behavior:TextChangedBehavior/>
</SearchBar.Behaviors>
</SearchBar>
<ListView x:Name="listView" ItemsSource="{Binding LebensmittelList}" HasUnevenRows="True">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout VerticalOptions="FillAndExpand" Orientation="Horizontal" Padding="10">
<Label Text="{Binding Name}" YAlign="Center" Font="Large"/>
<ia:Checkbox HorizontalOptions="EndAndExpand"/>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
</ContentPage.Content>
Einkaufsliste.xaml.cs
public Einkaufsliste ()
{
InitializeComponent ();
BindingContext = new LebensmittelViewModel();
}
I think everything should be okay but it's not working.
Hope someone could help me with this,
thanks
Edit for Tom:
public void RefreshListView(string searchBarText)
{
addItemInCollection(searchBarText);
}
public void addItemInCollection(string searchBarText)
{
if (searchBarText != null)
{
foreach (var item in normalLebensmittelList)
{
if (item.Name.Contains(searchBarText) || item.Name.Contains(searchBarText.First().ToString().ToUpper()))
{
AddItemToList(item);
};
}
}
}
private void AddItemToList(Lebensmittel item)
{
lebensmittelList.Add(item);
LebensmittelList = lebensmittelList;
}
c# listview xamarin xamarin.forms
c# listview xamarin xamarin.forms
asked Nov 20 '18 at 16:57
Marvin LMarvin L
54
asked Nov 20 '18 at 16:57
Marvin LMarvin L
54
edited Nov 21 '18 at 12:25
Marvin L
asked Nov 20 '18 at 16:57
Marvin LMarvin L
54
asked Nov 20 '18 at 16:57
Marvin LMarvin L
54
asked Nov 20 '18 at 16:57
Marvin LMarvin L
54
54
add a comment |
add a comment |
5 Answers
5
active
oldest
votes
How it's implemented the behavior TextChangedBehavior? Do you cast the BindingContext as a LebensmittelViewModel in order to call RefreshListView?
I would get rid of the behavior :/ and add a TextChanged event, create the property SearchBarText, since I don't see where it's declared and you're binding it to the SearchBar, refactor the RefreshListView method... and I think that it should work... :)
Einkaufsliste.xaml.cs
private LebensmittelViewModel vm = new LebensmittelViewModel();
public Einkaufsliste ()
{
InitializeComponent ();
BindingContext = vm;
}
public void OnSeachBarTextChange(object e, TextChangedEventArgs args)
{
vm.RefreshListView();
}
Einkaufsliste.xaml
<ContentPage.Content>
<StackLayout Spacing="10" Padding="10">
<SearchBar x:Name="searchBar" Text="{Binding SearchBarText, Mode=TwoWay}" Placeholder="Lebensmittel suchen..." VerticalOptions="StartAndExpand" TextChanged="OnSeachBarTextChange">
</SearchBar>
<ListView x:Name="listView" ItemsSource="{Binding LebensmittelList}" HasUnevenRows="True">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout VerticalOptions="FillAndExpand" Orientation="Horizontal" Padding="10">
<Label Text="{Binding Name}" YAlign="Center" Font="Large"/>
<ia:Checkbox HorizontalOptions="EndAndExpand"/>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
</ContentPage.Content>
Viewmodel
private string _searchBarText;
public string SearchBarText
{
get
{
return _searchBarText;
}
set
{
_searchBarText = value;
OnPropertyChanged("SearchBarText");
}
}
public void RefreshListView()
{
if (!string.IsNullOrEmpty(searchBarText))
{
var matches = normalLebensmittelList.Where(x => x.Name.Contains(searchBarText) || x.Name.Contains(searchBarText.First().ToString().ToUpper())
foreach (var item in matches)
{
LebensmittelList.Add(item);
}
}
}
answered Nov 21 '18 at 11:55
jjchiwjjchiw
3,2952427
omg its working, thank you so much!
– Marvin L
Nov 21 '18 at 12:30
add a comment |
Can you try replacing the Following method:
public void RefreshListView(string searchBarText)
{
LebensmittelList.Clear();
addItemInCollection(searchBarText);
}
Since you are already using the Observable Collection you dont need to replace the collection. You can add and it will automatically observed and binded. Let me know if it works!
answered Nov 20 '18 at 17:44
Nirmal SubediNirmal Subedi
1,4382923
Thanks for the fast reply but this is not working :/
– Marvin L
Nov 20 '18 at 17:54
add a comment |
It looks like you have extra work with LebensmittelList. Try do the following:
public void RefreshListView(string searchBarText)
{
// this can be list clearing, if you need it
addItemInCollection(searchBarText);
OnPropertyChanged("LebensmittelList");
}
public void addItemInCollection(string searchBarText)
{
if (searchBarText != null)
{
foreach (var item in normalLebensmittelList)
{
if (item.Name.Contains(searchBarText) || item.Name.Contains(searchBarText.First().ToString().ToUpper()))
{
LebensmittelList.Add(item);
};
}
}
}
Edit:
I don't know if anyone can call this solution elegant, but it should work.
internal class MyCollection<T> : ObservableCollection<T>
{
public void DoCollectionChanged()
{
OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
}
}
... MyCollection<LebensmittelItem> LebensmittelList; // field and property declaration should be changed
public void RefreshListView(string searchBarText)
{
// this can be list clearing, if you need it
addItemInCollection(searchBarText);
LebensmittelList.DoCollectionChanged();
}
answered Nov 20 '18 at 19:43
MiamyMiamy
1,083715
thanks but not working :/
– Marvin L
Nov 20 '18 at 19:58
I updated the answer, please try this.
– Miamy
Nov 20 '18 at 20:25
Not working :/ but thanks anyway
– Marvin L
Nov 20 '18 at 21:42
add a comment |
Is OnPropertyChanged in the property set called when you do the RefreshListView?
answered Nov 21 '18 at 9:27
Alexander UddfeldtAlexander Uddfeldt
2066
Yes it its in and it jumps also into this but nothing is working
– Marvin L
Nov 21 '18 at 10:43
add a comment |
In the addItemToCollection method, you are calling the following line:
LebensmittelList.Add(item);
In this case LebensmittelList is a property, not a variable. The line LebensmittelList.Add(item); is effectively doing the following:
var temporaryList = LebensmittelList; // Gets lebensmittelList and assigns to temporaryList
temporaryList.Add(item); // You add the item to the *variable temporaryList*
Essentially, you are adding to an instance of lebensmittelList (a temporary copy), and not the lebensmittelList variable. Once you have added that item to the temporary list, the whole (temporary) list gets discarded without "saving changes".
To actually update LebensmittelList, you would be better off calling a method like:
private void AddItemToList(object item)
{
lebensmittelList.Add(item);
LebensmittelList = lebensmittelList;
}
answered Nov 21 '18 at 11:04
TomTom
1,112717
Unfortunately does not work :/ I can upload my whole project somewhere
– Marvin L
Nov 21 '18 at 11:47
Can you post what you have tried?
– Tom
Nov 21 '18 at 12:14
I added it for you in my original post
– Marvin L
Nov 21 '18 at 12:25
add a comment |
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5 Answers
5
active
oldest
votes
5 Answers
5
active
oldest
votes
active
oldest
votes
active
oldest
votes
How it's implemented the behavior TextChangedBehavior? Do you cast the BindingContext as a LebensmittelViewModel in order to call RefreshListView?
I would get rid of the behavior :/ and add a TextChanged event, create the property SearchBarText, since I don't see where it's declared and you're binding it to the SearchBar, refactor the RefreshListView method... and I think that it should work... :)
Einkaufsliste.xaml.cs
private LebensmittelViewModel vm = new LebensmittelViewModel();
public Einkaufsliste ()
{
InitializeComponent ();
BindingContext = vm;
}
public void OnSeachBarTextChange(object e, TextChangedEventArgs args)
{
vm.RefreshListView();
}
Einkaufsliste.xaml
<ContentPage.Content>
<StackLayout Spacing="10" Padding="10">
<SearchBar x:Name="searchBar" Text="{Binding SearchBarText, Mode=TwoWay}" Placeholder="Lebensmittel suchen..." VerticalOptions="StartAndExpand" TextChanged="OnSeachBarTextChange">
</SearchBar>
<ListView x:Name="listView" ItemsSource="{Binding LebensmittelList}" HasUnevenRows="True">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout VerticalOptions="FillAndExpand" Orientation="Horizontal" Padding="10">
<Label Text="{Binding Name}" YAlign="Center" Font="Large"/>
<ia:Checkbox HorizontalOptions="EndAndExpand"/>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
</ContentPage.Content>
Viewmodel
private string _searchBarText;
public string SearchBarText
{
get
{
return _searchBarText;
}
set
{
_searchBarText = value;
OnPropertyChanged("SearchBarText");
}
}
public void RefreshListView()
{
if (!string.IsNullOrEmpty(searchBarText))
{
var matches = normalLebensmittelList.Where(x => x.Name.Contains(searchBarText) || x.Name.Contains(searchBarText.First().ToString().ToUpper())
foreach (var item in matches)
{
LebensmittelList.Add(item);
}
}
}
answered Nov 21 '18 at 11:55
jjchiwjjchiw
3,2952427
omg its working, thank you so much!
– Marvin L
Nov 21 '18 at 12:30
add a comment |
How it's implemented the behavior TextChangedBehavior? Do you cast the BindingContext as a LebensmittelViewModel in order to call RefreshListView?
I would get rid of the behavior :/ and add a TextChanged event, create the property SearchBarText, since I don't see where it's declared and you're binding it to the SearchBar, refactor the RefreshListView method... and I think that it should work... :)
Einkaufsliste.xaml.cs
private LebensmittelViewModel vm = new LebensmittelViewModel();
public Einkaufsliste ()
{
InitializeComponent ();
BindingContext = vm;
}
public void OnSeachBarTextChange(object e, TextChangedEventArgs args)
{
vm.RefreshListView();
}
Einkaufsliste.xaml
<ContentPage.Content>
<StackLayout Spacing="10" Padding="10">
<SearchBar x:Name="searchBar" Text="{Binding SearchBarText, Mode=TwoWay}" Placeholder="Lebensmittel suchen..." VerticalOptions="StartAndExpand" TextChanged="OnSeachBarTextChange">
</SearchBar>
<ListView x:Name="listView" ItemsSource="{Binding LebensmittelList}" HasUnevenRows="True">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout VerticalOptions="FillAndExpand" Orientation="Horizontal" Padding="10">
<Label Text="{Binding Name}" YAlign="Center" Font="Large"/>
<ia:Checkbox HorizontalOptions="EndAndExpand"/>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
</ContentPage.Content>
Viewmodel
private string _searchBarText;
public string SearchBarText
{
get
{
return _searchBarText;
}
set
{
_searchBarText = value;
OnPropertyChanged("SearchBarText");
}
}
public void RefreshListView()
{
if (!string.IsNullOrEmpty(searchBarText))
{
var matches = normalLebensmittelList.Where(x => x.Name.Contains(searchBarText) || x.Name.Contains(searchBarText.First().ToString().ToUpper())
foreach (var item in matches)
{
LebensmittelList.Add(item);
}
}
}
answered Nov 21 '18 at 11:55
jjchiwjjchiw
3,2952427
omg its working, thank you so much!
– Marvin L
Nov 21 '18 at 12:30
add a comment |
How it's implemented the behavior TextChangedBehavior? Do you cast the BindingContext as a LebensmittelViewModel in order to call RefreshListView?
I would get rid of the behavior :/ and add a TextChanged event, create the property SearchBarText, since I don't see where it's declared and you're binding it to the SearchBar, refactor the RefreshListView method... and I think that it should work... :)
Einkaufsliste.xaml.cs
private LebensmittelViewModel vm = new LebensmittelViewModel();
public Einkaufsliste ()
{
InitializeComponent ();
BindingContext = vm;
}
public void OnSeachBarTextChange(object e, TextChangedEventArgs args)
{
vm.RefreshListView();
}
Einkaufsliste.xaml
<ContentPage.Content>
<StackLayout Spacing="10" Padding="10">
<SearchBar x:Name="searchBar" Text="{Binding SearchBarText, Mode=TwoWay}" Placeholder="Lebensmittel suchen..." VerticalOptions="StartAndExpand" TextChanged="OnSeachBarTextChange">
</SearchBar>
<ListView x:Name="listView" ItemsSource="{Binding LebensmittelList}" HasUnevenRows="True">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout VerticalOptions="FillAndExpand" Orientation="Horizontal" Padding="10">
<Label Text="{Binding Name}" YAlign="Center" Font="Large"/>
<ia:Checkbox HorizontalOptions="EndAndExpand"/>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
</ContentPage.Content>
Viewmodel
private string _searchBarText;
public string SearchBarText
{
get
{
return _searchBarText;
}
set
{
_searchBarText = value;
OnPropertyChanged("SearchBarText");
}
}
public void RefreshListView()
{
if (!string.IsNullOrEmpty(searchBarText))
{
var matches = normalLebensmittelList.Where(x => x.Name.Contains(searchBarText) || x.Name.Contains(searchBarText.First().ToString().ToUpper())
foreach (var item in matches)
{
LebensmittelList.Add(item);
}
}
}
answered Nov 21 '18 at 11:55
jjchiwjjchiw
3,2952427
How it's implemented the behavior TextChangedBehavior? Do you cast the BindingContext as a LebensmittelViewModel in order to call RefreshListView?
I would get rid of the behavior :/ and add a TextChanged event, create the property SearchBarText, since I don't see where it's declared and you're binding it to the SearchBar, refactor the RefreshListView method... and I think that it should work... :)
Einkaufsliste.xaml.cs
private LebensmittelViewModel vm = new LebensmittelViewModel();
public Einkaufsliste ()
{
InitializeComponent ();
BindingContext = vm;
}
public void OnSeachBarTextChange(object e, TextChangedEventArgs args)
{
vm.RefreshListView();
}
Einkaufsliste.xaml
<ContentPage.Content>
<StackLayout Spacing="10" Padding="10">
<SearchBar x:Name="searchBar" Text="{Binding SearchBarText, Mode=TwoWay}" Placeholder="Lebensmittel suchen..." VerticalOptions="StartAndExpand" TextChanged="OnSeachBarTextChange">
</SearchBar>
<ListView x:Name="listView" ItemsSource="{Binding LebensmittelList}" HasUnevenRows="True">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout VerticalOptions="FillAndExpand" Orientation="Horizontal" Padding="10">
<Label Text="{Binding Name}" YAlign="Center" Font="Large"/>
<ia:Checkbox HorizontalOptions="EndAndExpand"/>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
</ContentPage.Content>
Viewmodel
private string _searchBarText;
public string SearchBarText
{
get
{
return _searchBarText;
}
set
{
_searchBarText = value;
OnPropertyChanged("SearchBarText");
}
}
public void RefreshListView()
{
if (!string.IsNullOrEmpty(searchBarText))
{
var matches = normalLebensmittelList.Where(x => x.Name.Contains(searchBarText) || x.Name.Contains(searchBarText.First().ToString().ToUpper())
foreach (var item in matches)
{
LebensmittelList.Add(item);
}
}
}
answered Nov 21 '18 at 11:55
jjchiwjjchiw
3,2952427
edited Nov 21 '18 at 12:01
answered Nov 21 '18 at 11:55
jjchiwjjchiw
3,2952427
answered Nov 21 '18 at 11:55
jjchiwjjchiw
3,2952427
answered Nov 21 '18 at 11:55
jjchiwjjchiw
3,2952427
3,2952427
omg its working, thank you so much!
– Marvin L
Nov 21 '18 at 12:30
add a comment |
omg its working, thank you so much!
– Marvin L
Nov 21 '18 at 12:30
omg its working, thank you so much!
– Marvin L
Nov 21 '18 at 12:30
omg its working, thank you so much!
– Marvin L
Nov 21 '18 at 12:30
add a comment |
Can you try replacing the Following method:
public void RefreshListView(string searchBarText)
{
LebensmittelList.Clear();
addItemInCollection(searchBarText);
}
Since you are already using the Observable Collection you dont need to replace the collection. You can add and it will automatically observed and binded. Let me know if it works!
answered Nov 20 '18 at 17:44
Nirmal SubediNirmal Subedi
1,4382923
Thanks for the fast reply but this is not working :/
– Marvin L
Nov 20 '18 at 17:54
add a comment |
Can you try replacing the Following method:
public void RefreshListView(string searchBarText)
{
LebensmittelList.Clear();
addItemInCollection(searchBarText);
}
Since you are already using the Observable Collection you dont need to replace the collection. You can add and it will automatically observed and binded. Let me know if it works!
answered Nov 20 '18 at 17:44
Nirmal SubediNirmal Subedi
1,4382923
Thanks for the fast reply but this is not working :/
– Marvin L
Nov 20 '18 at 17:54
add a comment |
Can you try replacing the Following method:
public void RefreshListView(string searchBarText)
{
LebensmittelList.Clear();
addItemInCollection(searchBarText);
}
Since you are already using the Observable Collection you dont need to replace the collection. You can add and it will automatically observed and binded. Let me know if it works!
answered Nov 20 '18 at 17:44
Nirmal SubediNirmal Subedi
1,4382923
Can you try replacing the Following method:
public void RefreshListView(string searchBarText)
{
LebensmittelList.Clear();
addItemInCollection(searchBarText);
}
Since you are already using the Observable Collection you dont need to replace the collection. You can add and it will automatically observed and binded. Let me know if it works!
answered Nov 20 '18 at 17:44
Nirmal SubediNirmal Subedi
1,4382923
answered Nov 20 '18 at 17:44
Nirmal SubediNirmal Subedi
1,4382923
answered Nov 20 '18 at 17:44
Nirmal SubediNirmal Subedi
1,4382923
answered Nov 20 '18 at 17:44
Nirmal SubediNirmal Subedi
1,4382923
1,4382923
Thanks for the fast reply but this is not working :/
– Marvin L
Nov 20 '18 at 17:54
add a comment |
Thanks for the fast reply but this is not working :/
– Marvin L
Nov 20 '18 at 17:54
Thanks for the fast reply but this is not working :/
– Marvin L
Nov 20 '18 at 17:54
Thanks for the fast reply but this is not working :/
– Marvin L
Nov 20 '18 at 17:54
add a comment |
It looks like you have extra work with LebensmittelList. Try do the following:
public void RefreshListView(string searchBarText)
{
// this can be list clearing, if you need it
addItemInCollection(searchBarText);
OnPropertyChanged("LebensmittelList");
}
public void addItemInCollection(string searchBarText)
{
if (searchBarText != null)
{
foreach (var item in normalLebensmittelList)
{
if (item.Name.Contains(searchBarText) || item.Name.Contains(searchBarText.First().ToString().ToUpper()))
{
LebensmittelList.Add(item);
};
}
}
}
Edit:
I don't know if anyone can call this solution elegant, but it should work.
internal class MyCollection<T> : ObservableCollection<T>
{
public void DoCollectionChanged()
{
OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
}
}
... MyCollection<LebensmittelItem> LebensmittelList; // field and property declaration should be changed
public void RefreshListView(string searchBarText)
{
// this can be list clearing, if you need it
addItemInCollection(searchBarText);
LebensmittelList.DoCollectionChanged();
}
answered Nov 20 '18 at 19:43
MiamyMiamy
1,083715
thanks but not working :/
– Marvin L
Nov 20 '18 at 19:58
I updated the answer, please try this.
– Miamy
Nov 20 '18 at 20:25
Not working :/ but thanks anyway
– Marvin L
Nov 20 '18 at 21:42
add a comment |
It looks like you have extra work with LebensmittelList. Try do the following:
public void RefreshListView(string searchBarText)
{
// this can be list clearing, if you need it
addItemInCollection(searchBarText);
OnPropertyChanged("LebensmittelList");
}
public void addItemInCollection(string searchBarText)
{
if (searchBarText != null)
{
foreach (var item in normalLebensmittelList)
{
if (item.Name.Contains(searchBarText) || item.Name.Contains(searchBarText.First().ToString().ToUpper()))
{
LebensmittelList.Add(item);
};
}
}
}
Edit:
I don't know if anyone can call this solution elegant, but it should work.
internal class MyCollection<T> : ObservableCollection<T>
{
public void DoCollectionChanged()
{
OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
}
}
... MyCollection<LebensmittelItem> LebensmittelList; // field and property declaration should be changed
public void RefreshListView(string searchBarText)
{
// this can be list clearing, if you need it
addItemInCollection(searchBarText);
LebensmittelList.DoCollectionChanged();
}
answered Nov 20 '18 at 19:43
MiamyMiamy
1,083715
thanks but not working :/
– Marvin L
Nov 20 '18 at 19:58
I updated the answer, please try this.
– Miamy
Nov 20 '18 at 20:25
Not working :/ but thanks anyway
– Marvin L
Nov 20 '18 at 21:42
add a comment |
It looks like you have extra work with LebensmittelList. Try do the following:
public void RefreshListView(string searchBarText)
{
// this can be list clearing, if you need it
addItemInCollection(searchBarText);
OnPropertyChanged("LebensmittelList");
}
public void addItemInCollection(string searchBarText)
{
if (searchBarText != null)
{
foreach (var item in normalLebensmittelList)
{
if (item.Name.Contains(searchBarText) || item.Name.Contains(searchBarText.First().ToString().ToUpper()))
{
LebensmittelList.Add(item);
};
}
}
}
Edit:
I don't know if anyone can call this solution elegant, but it should work.
internal class MyCollection<T> : ObservableCollection<T>
{
public void DoCollectionChanged()
{
OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
}
}
... MyCollection<LebensmittelItem> LebensmittelList; // field and property declaration should be changed
public void RefreshListView(string searchBarText)
{
// this can be list clearing, if you need it
addItemInCollection(searchBarText);
LebensmittelList.DoCollectionChanged();
}
answered Nov 20 '18 at 19:43
MiamyMiamy
1,083715
It looks like you have extra work with LebensmittelList. Try do the following:
public void RefreshListView(string searchBarText)
{
// this can be list clearing, if you need it
addItemInCollection(searchBarText);
OnPropertyChanged("LebensmittelList");
}
public void addItemInCollection(string searchBarText)
{
if (searchBarText != null)
{
foreach (var item in normalLebensmittelList)
{
if (item.Name.Contains(searchBarText) || item.Name.Contains(searchBarText.First().ToString().ToUpper()))
{
LebensmittelList.Add(item);
};
}
}
}
Edit:
I don't know if anyone can call this solution elegant, but it should work.
internal class MyCollection<T> : ObservableCollection<T>
{
public void DoCollectionChanged()
{
OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
}
}
... MyCollection<LebensmittelItem> LebensmittelList; // field and property declaration should be changed
public void RefreshListView(string searchBarText)
{
// this can be list clearing, if you need it
addItemInCollection(searchBarText);
LebensmittelList.DoCollectionChanged();
}
answered Nov 20 '18 at 19:43
MiamyMiamy
1,083715
edited Nov 20 '18 at 20:24
answered Nov 20 '18 at 19:43
MiamyMiamy
1,083715
answered Nov 20 '18 at 19:43
MiamyMiamy
1,083715
answered Nov 20 '18 at 19:43
MiamyMiamy
1,083715
1,083715
thanks but not working :/
– Marvin L
Nov 20 '18 at 19:58
I updated the answer, please try this.
– Miamy
Nov 20 '18 at 20:25
Not working :/ but thanks anyway
– Marvin L
Nov 20 '18 at 21:42
add a comment |
thanks but not working :/
– Marvin L
Nov 20 '18 at 19:58
I updated the answer, please try this.
– Miamy
Nov 20 '18 at 20:25
Not working :/ but thanks anyway
– Marvin L
Nov 20 '18 at 21:42
thanks but not working :/
– Marvin L
Nov 20 '18 at 19:58
thanks but not working :/
– Marvin L
Nov 20 '18 at 19:58
I updated the answer, please try this.
– Miamy
Nov 20 '18 at 20:25
I updated the answer, please try this.
– Miamy
Nov 20 '18 at 20:25
Not working :/ but thanks anyway
– Marvin L
Nov 20 '18 at 21:42
Not working :/ but thanks anyway
– Marvin L
Nov 20 '18 at 21:42
add a comment |
Is OnPropertyChanged in the property set called when you do the RefreshListView?
answered Nov 21 '18 at 9:27
Alexander UddfeldtAlexander Uddfeldt
2066
Yes it its in and it jumps also into this but nothing is working
– Marvin L
Nov 21 '18 at 10:43
add a comment |
Is OnPropertyChanged in the property set called when you do the RefreshListView?
answered Nov 21 '18 at 9:27
Alexander UddfeldtAlexander Uddfeldt
2066
Yes it its in and it jumps also into this but nothing is working
– Marvin L
Nov 21 '18 at 10:43
add a comment |
Is OnPropertyChanged in the property set called when you do the RefreshListView?
answered Nov 21 '18 at 9:27
Alexander UddfeldtAlexander Uddfeldt
2066
Is OnPropertyChanged in the property set called when you do the RefreshListView?
answered Nov 21 '18 at 9:27
Alexander UddfeldtAlexander Uddfeldt
2066
answered Nov 21 '18 at 9:27
Alexander UddfeldtAlexander Uddfeldt
2066
answered Nov 21 '18 at 9:27
Alexander UddfeldtAlexander Uddfeldt
2066
answered Nov 21 '18 at 9:27
Alexander UddfeldtAlexander Uddfeldt
2066
2066
Yes it its in and it jumps also into this but nothing is working
– Marvin L
Nov 21 '18 at 10:43
add a comment |
Yes it its in and it jumps also into this but nothing is working
– Marvin L
Nov 21 '18 at 10:43
Yes it its in and it jumps also into this but nothing is working
– Marvin L
Nov 21 '18 at 10:43
Yes it its in and it jumps also into this but nothing is working
– Marvin L
Nov 21 '18 at 10:43
add a comment |
In the addItemToCollection method, you are calling the following line:
LebensmittelList.Add(item);
In this case LebensmittelList is a property, not a variable. The line LebensmittelList.Add(item); is effectively doing the following:
var temporaryList = LebensmittelList; // Gets lebensmittelList and assigns to temporaryList
temporaryList.Add(item); // You add the item to the *variable temporaryList*
Essentially, you are adding to an instance of lebensmittelList (a temporary copy), and not the lebensmittelList variable. Once you have added that item to the temporary list, the whole (temporary) list gets discarded without "saving changes".
To actually update LebensmittelList, you would be better off calling a method like:
private void AddItemToList(object item)
{
lebensmittelList.Add(item);
LebensmittelList = lebensmittelList;
}
answered Nov 21 '18 at 11:04
TomTom
1,112717
Unfortunately does not work :/ I can upload my whole project somewhere
– Marvin L
Nov 21 '18 at 11:47
Can you post what you have tried?
– Tom
Nov 21 '18 at 12:14
I added it for you in my original post
– Marvin L
Nov 21 '18 at 12:25
add a comment |
In the addItemToCollection method, you are calling the following line:
LebensmittelList.Add(item);
In this case LebensmittelList is a property, not a variable. The line LebensmittelList.Add(item); is effectively doing the following:
var temporaryList = LebensmittelList; // Gets lebensmittelList and assigns to temporaryList
temporaryList.Add(item); // You add the item to the *variable temporaryList*
Essentially, you are adding to an instance of lebensmittelList (a temporary copy), and not the lebensmittelList variable. Once you have added that item to the temporary list, the whole (temporary) list gets discarded without "saving changes".
To actually update LebensmittelList, you would be better off calling a method like:
private void AddItemToList(object item)
{
lebensmittelList.Add(item);
LebensmittelList = lebensmittelList;
}
answered Nov 21 '18 at 11:04
TomTom
1,112717
Unfortunately does not work :/ I can upload my whole project somewhere
– Marvin L
Nov 21 '18 at 11:47
Can you post what you have tried?
– Tom
Nov 21 '18 at 12:14
I added it for you in my original post
– Marvin L
Nov 21 '18 at 12:25
add a comment |
In the addItemToCollection method, you are calling the following line:
LebensmittelList.Add(item);
In this case LebensmittelList is a property, not a variable. The line LebensmittelList.Add(item); is effectively doing the following:
var temporaryList = LebensmittelList; // Gets lebensmittelList and assigns to temporaryList
temporaryList.Add(item); // You add the item to the *variable temporaryList*
Essentially, you are adding to an instance of lebensmittelList (a temporary copy), and not the lebensmittelList variable. Once you have added that item to the temporary list, the whole (temporary) list gets discarded without "saving changes".
To actually update LebensmittelList, you would be better off calling a method like:
private void AddItemToList(object item)
{
lebensmittelList.Add(item);
LebensmittelList = lebensmittelList;
}
answered Nov 21 '18 at 11:04
TomTom
1,112717
In the addItemToCollection method, you are calling the following line:
LebensmittelList.Add(item);
In this case LebensmittelList is a property, not a variable. The line LebensmittelList.Add(item); is effectively doing the following:
var temporaryList = LebensmittelList; // Gets lebensmittelList and assigns to temporaryList
temporaryList.Add(item); // You add the item to the *variable temporaryList*
Essentially, you are adding to an instance of lebensmittelList (a temporary copy), and not the lebensmittelList variable. Once you have added that item to the temporary list, the whole (temporary) list gets discarded without "saving changes".
To actually update LebensmittelList, you would be better off calling a method like:
private void AddItemToList(object item)
{
lebensmittelList.Add(item);
LebensmittelList = lebensmittelList;
}
answered Nov 21 '18 at 11:04
TomTom
1,112717
answered Nov 21 '18 at 11:04
TomTom
1,112717
answered Nov 21 '18 at 11:04
TomTom
1,112717
answered Nov 21 '18 at 11:04
TomTom
1,112717
1,112717
Unfortunately does not work :/ I can upload my whole project somewhere
– Marvin L
Nov 21 '18 at 11:47
Can you post what you have tried?
– Tom
Nov 21 '18 at 12:14
I added it for you in my original post
– Marvin L
Nov 21 '18 at 12:25
add a comment |
Unfortunately does not work :/ I can upload my whole project somewhere
– Marvin L
Nov 21 '18 at 11:47
Can you post what you have tried?
– Tom
Nov 21 '18 at 12:14
I added it for you in my original post
– Marvin L
Nov 21 '18 at 12:25
Unfortunately does not work :/ I can upload my whole project somewhere
– Marvin L
Nov 21 '18 at 11:47
Unfortunately does not work :/ I can upload my whole project somewhere
– Marvin L
Nov 21 '18 at 11:47
Can you post what you have tried?
– Tom
Nov 21 '18 at 12:14
Can you post what you have tried?
– Tom
Nov 21 '18 at 12:14
I added it for you in my original post
– Marvin L
Nov 21 '18 at 12:25
I added it for you in my original post
– Marvin L
Nov 21 '18 at 12:25
add a comment |
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