I have a ListView with several items in it. I am running the app as a UWP app on my local machine, but for some reason, displaying an image via a url doesn't work?
The tag I'm using is
<Image Source="https://en.bitcoin.it/w/images/en/2/29/BC_Logo_.png" HeightRequest="20" WidthRequest="20" />
I have tried using several different images from different domains as I thought it could be an authorisation issue? But no images that I've tried seem to be working.
As I define the space for the image, there is a gap in the list where it should be.
For reference, here is the whole list code:
<ContentPage Title="Coins">
<ContentPage.Content>
<ListView x:Name="coins" HasUnevenRows="True">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<ViewCell.View>
<StackLayout Spacing="5" Orientation="Horizontal" Padding="10,10,10,10">
<Label Text="{Binding Path=Rank}" FontSize="10" VerticalTextAlignment="Center"/>
<Image Source="https://en.bitcoin.it/w/images/en/2/29/BC_Logo_.png" HeightRequest="20" WidthRequest="20" />
<Label Text="{Binding Path=Name}" TextColor="Black" FontSize="19" VerticalTextAlignment="Center"/>
<Label Text="{Binding Path=PercentChange24h, StringFormat='{0}%'}" VerticalTextAlignment="Center" TextColor="{Binding PercentTextColour}"/>
<Label Text="{Binding Path=LivePrice, StringFormat='${0}'}" VerticalTextAlignment="Center" HorizontalTextAlignment="End" HorizontalOptions="EndAndExpand"/>
</StackLayout>
</ViewCell.View>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</ContentPage.Content>
</ContentPage>
This issue was down to UWP not being able to display images, this works on Android and iOS.
Related
How to keep the built-in Header of a ListView frozen to the top when scrolling vertically down through the ListView items?
Before flagging as duplicate: I tried to apply answers in Keep ListView.HeaderTemplate visible/static/sticky in UWP for Xamarin.Forms targeting Android without success.
Short code sample:
<ListView ItemsSource="{Binding MyList}"
HasUnevenRows="True"
SeparatorVisibility="Default"
CachingStrategy="RecycleElement">
<ListView.Header>
<Label HorizontalTextAlignment="Center"
FontAttributes="Bold"
Text="Header Title"/>
</ListView.Header>
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<Label Text="{Binding Name}"/>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
Here is an alternative approach to this if the list isn't long
<StackLayout>
<Label HorizontalTextAlignment="Center"
FontAttributes="Bold"
Text="Header Title"/>
<StackLayout BindableLayout.ItemsSource="{Binding MyList}">
<BindableLayout.ItemTemplate>
<DataTemplate>
<StackLayout>
<Label Text="{Binding Name}"/>
<!-- boxview as separator -->
<BoxView HeightRequest="1" Color="Aqua" HorizontalOptions="FillAndExpand"/>
</StackLayout>
</DataTemplate>
</BindableLayout.ItemTemplate>
</StackLayout>
</StackLayout>
I have implemented a listview and in each item I want to have two labels, in each end horizontally. But in reality it just put the two labels next to eachother left aligned.
I read that maybe this is not possible with a stacklayout, as it doesn't take up more space than needed. (Even tried fill and fillandExpand which didn't help.)
Instead I should use a grid. But I have options on my listview, as grouping, refresh, caching, tapped, which I guess I don't have on a grid?
I would like to succeed with a listview if that is possible. Anyone have some insights to this layout issue?
Here is my xaml code:
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="MyApp.Page.ItemsTest">
<ListView x:Name="ItemView"
ItemsSource="{Binding ItemGroup}"
CachingStrategy="RecycleElement"
IsGroupingEnabled="true"
HasUnevenRows="True"
ItemTapped="Handle_ItemTapped">
<ListView.GroupHeaderTemplate>
<DataTemplate>
<ViewCell>
<StackLayout BackgroundColor="#FFA500" Orientation="Vertical" Padding="10">
<StackLayout Orientation="Horizontal">
<Label Text="{Binding Heading}" TextColor="White" FontAttributes="Bold" />
</StackLayout>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.GroupHeaderTemplate>
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout Orientation="Horizontal" Padding="10" HorizontalOptions="FillAndExpand">
<Label Text="{Binding Name}" FontAttributes="Bold" HorizontalTextAlignment="Start"/>
<Label Text="{Binding Start, StringFormat='{0:HH:mm}'}" FontAttributes="Bold" HorizontalTextAlignment="End"/>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</ContentPage>
Central part is this:
<StackLayout Orientation="Horizontal" Padding="10" HorizontalOptions="FillAndExpand">
<Label Text="{Binding Name}" FontAttributes="Bold" HorizontalTextAlignment="Start"/>
<Label Text="{Binding Start, StringFormat='{0:HH:mm}'}" FontAttributes="Bold" HorizontalTextAlignment="End"/>
</StackLayout>
Update:
As requested I have a colored the background of the two labels and the stacklayout. It's the same output if I use HorizontalOptions="End" and HorizontalTextAlignment="End" at the same time or each one alone. Also if I remove the HorizontalOptions="FillAndExpand" on the stacklayout, it's still the exact same graphical output. (The orange color was already present)
Maybe you could use a Grid instead of the StackLayout and place each Label in a different Column:
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"></ColumnDefinition>
<ColumnDefinition Width="*"></ColumnDefinition>
</Grid.ColumnDefinitions>
<Label Grid.Column="0" Text="{Binding Name}" FontAttributes="Bold" HorizontalTextAlignment="Start"/>
<Label Grid.Column="1" Text="{Binding Start, StringFormat='{0:HH:mm}'}" FontAttributes="Bold" HorizontalTextAlignment="End"/>
</Grid>
You could also use nested StackLayout
<StackLayout>
<Label />
<Label Text="Gender:" FontAttributes="Bold"/>
<StackLayout Orientation="Horizontal">
<Label HorizontalOptions="Start" Text="First Name: " FontAttributes="Bold"/>
<Entry HorizontalOptions="EndAndExpand" Placeholder="First Name" MaxLength="256" Text="{Binding FirstName}"></Entry>
</StackLayout>
</StackLayout>
Am working small Xamarin.forms application.Now i have doubt to how to count and display list items in label
like email and gmail.
I'm browsing in google various sites i did't get result
My Xaml code is below how to display count in side bar and i used grid for that sum Xaml.task error will be occur
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:emit="clr-namespace:System.Reflection.Emit;assembly=mscorlib"
x:Class="vMonitor.Views.HomeListView"
Title="Home List View"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008">
<ScrollView>
<StackLayout Orientation="Vertical">
<ListView ItemsSource="{Binding Model}" Margin="20,0,20,0"
x:Name="listView"
SeparatorVisibility="Default" SeparatorColor="Brown"
HasUnevenRows="True">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<Grid>
<StackLayout Orientation="Horizontal" Padding="10">
<Label Text="{Binding Name}" FontSize="20" FontFamily="TimesNewRomen" FontAttributes="None">
<Label.GestureRecognizers>
<TapGestureRecognizer Command="{Binding Path=BindingContext.TabCommand, Source={x:Reference listView}}" CommandParameter="{Binding .}"/>
</Label.GestureRecognizers>
</Label>
<Label Text="{Binding UserID}" FontSize="20" FontFamily="TimesNewRomen" FontAttributes="None"/>
</StackLayout>
</Grid>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
</ScrollView>
</ContentPage>
Then you can use ViewCell for List Item.
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout Padding="15,10" Orientation="Horizontal">
<Label
VerticalTextAlignment="Center"
Text="{Binding ItemName}" TextColor="#FF1654" FontAttributes="Bold" FontSize="16"/>
<Label VerticalOptions="End"
VerticalTextAlignment="Center"
Text="{Binding ItemCount}" TextColor="#FF1654" FontAttributes="Bold" FontSize="16"/>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
You can Bind ItemName and ItemCount. If you want to Display Left Side Image then you can add Image at start position in ViewCell.
For Expandable you have to use IsVisible Property for that cell.
I am using DottorPagliaccius repeater view thats nested inside another repeaterview. The command RSSFeedSelectedCommand doesnt work unless on top repeater, which in theory makes sense but how can i get it to work?
I have looked into using Converters and bindtoeventcommand but cant see to get them working.
<repeater:RepeaterView x:Name="MainRepeater" SeparatorHeight="25" ItemsSource={Binding Feeds}">
<repeater:RepeaterView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout Spacing="10">
<Label Text="{Binding Title}" TextColor="Blue" />
<Label Text="{Binding Description}" TextColor="Red" FontSize="12" />
<repeater:RepeaterView x:Name="MainRepeater2" EmptyText="No elements" ShowSeparator="true" SeparatorHeight="2" SeparatorColor="Silver" ItemsSource="{Binding Items}" SelectedItemCommand="{Binding RSSFeedSelectedCommand}">
<repeater`enter code here`:RepeaterView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout Orientation="Horizontal">
<Image Source="{Binding Image.Url}"></Image>
<StackLayout Orientation="Vertical">
<Label Text="{Binding Title}" TextColor="Black" />
<Label Text="{Binding Description}" TextColor="Black" FontSize="12" />
</StackLayout>
</StackLayout>
</ViewCell>
</DataTemplate>
</repeater:RepeaterView.ItemTemplate>
</repeater:RepeaterView>
</StackLayout>
</ViewCell>
</DataTemplate>
</repeater:RepeaterView.ItemTemplate>
</repeater:RepeaterView>
The Repeater was trying to find the command in Feeds however exists in the ViewModel.
<repeater:RepeaterView x:Name="MainRepeater2" EmptyText="No elements" ShowSeparator="true" SeparatorHeight="2" SeparatorColor="Silver" ItemsSource="{Binding Items}" SelectedItemCommand="{Binding Source={x:Reference RSSPage}, Path=BindingContext.RSSFeedSelectedCommand}">
and you have to name the page:
<ContentPage x:Name="PageName" />
If my assumption is correct, your class structure should be something like,
ViewModel
|__List of Feeds
|__List of Items
|__RSSFeedSelectedCommand
So, DataContext of your inner repeater control (MainRepeater2) will be Feed. So, try with DataContext of outer repeater control. Like,
<repeater:RepeaterView x:Name="MainRepeater2" ItemsSource="{Binding Items}"
SelectedItemCommand="{Binding DataContext.RSSFeedSelectedCommand,
ElementName=MainRepeater}"/>
For Xamarin:
<repeater:RepeaterView x:Name="MainRepeater2" ItemsSource="{Binding Items}"
SelectedItemCommand="{Binding DataContext.RSSFeedSelectedCommand,
Source={x:Reference MainRepeater}}"/>
I have a page that contains a listview and Search bar control. There is a custom listview for android. My code as following:
<ContentPage.Content>
<ContentView>
<OnPlatform x:TypeArguments="View">
<OnPlatform.iOS>
<StackLayout Spacing="0">
<SearchBar x:Name="IosSearch"
Placeholder="Search"
TextChanged="IosSearchBar_OnTextChanged"
SearchButtonPressed="OnSearch" BackgroundColor="#19588F">
</SearchBar>
<ListView x:Name="EmpListViewIos"
ItemsSource="{Binding EmpModel.GroupedItems}"
ItemSelected="OnItemSelected"
SeparatorVisibility="Default">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout Padding="8">
<StackLayout Spacing="4" Orientation="Horizontal">
<Label Text="{Binding FullName}" FontSize="15" TextColor="Gray" LineBreakMode="NoWrap"/>
</StackLayout>
<StackLayout Spacing="4" Orientation="Horizontal">
<Label Text="{Binding Department}" FontSize="Small" TextColor="#F68933" LineBreakMode="WordWrap"/>
</StackLayout>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
</OnPlatform.iOS>
<OnPlatform.Android>
<StackLayout x:Name="androidListView">
<SearchBar x:Name="DroidSearch"
Placeholder="Search"
TextChanged="DroidSearchBar_OnTextChanged"
SearchButtonPressed="OnSearch" BackgroundColor="#19588F">
</SearchBar>
<local:CustomListView x:Name="customListView"
Items="{Binding EmpModel.Items}"
VerticalOptions="FillAndExpand" MyListItemSelected="nativeListView_ItemSelected"
SeparatorColor="Black">
</local:MyListView>
</StackLayout>
</OnPlatform.Android>
<OnPlatform.WinPhone>
<StackLayout Spacing="0">
<SearchBar x:Name="WinSearch"
Placeholder="Search"
TextChanged="WinSearchBar_OnTextChanged"
SearchButtonPressed="OnSearch" BackgroundColor="#19588F">
</SearchBar>
<ListView x:Name="EmpListViewWin"
ItemsSource="{Binding EmpModel.GroupedItems}"
ItemSelected="OnItemSelected"
SeparatorVisibility="Default">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout Padding="8">
<StackLayout Spacing="4" Orientation="Horizontal">
<Label Text="{Binding FullName}" FontSize="15" TextColor="Gray" LineBreakMode="NoWrap"/>
</StackLayout>
<StackLayout Spacing="4" Orientation="Horizontal">
<Label Text="{Binding Department}" FontSize="Small" TextColor="#F68933" LineBreakMode="WordWrap"/>
</StackLayout>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
</OnPlatform.WinPhone>
</OnPlatform>
</ContentView>
</ContentPage.Content>
</ContentPage>
As the representation of data is different due to that I am required custom listview for android according to it's layout defined. The above code works fine. The only problem is the redundancy, the search bar control is common for all platform but when I put the search bar control above the <ContentView> it doesn't work throws exception. Similarly the ListView is common for ios and windows only there is custom listview for android but I am forced to repeat the code for windows also same as android.
Can anyone suggest a more efficient way to achieve this. How can I apply platform specific condition only for android and common for windows and ios.
You could share the iOS and WinPhone views using a static resource:
<ContentPage>
<ContentPage.ResourceDictionary>
<StackLayout x:Key="iosOrWpView">
...
</StackLayout>
</ContentPage.ResourceDictionary>
<ContentView>
<OnPlatform x:TypeArguments="View" iOS="{StaticResource iosOrWpView}"
WinPhone="{StaticResource iosOrWpView}">
<OnPlatform.Android>
<StackLayout x:Name="androidListView">
...
</StackLayout>
</OnPlatform.Android>
</OnPlatform>
</ContentView>
<ContentPage>