Questions on UI for Xamarin Forum

3 answers

1.0K+ views

I have a scenario where I have "dynamic" content in a listview. I am making a sort of chat application where you can send hyperlinks, images, videos, etc.

I have a template defined in XAML for an incoming message and outgoing message, but I need to be able to say "this message has an image", "this message has a link", "this message has a text body with a link in the middle of it", "this message has both text and 2 images", etc.

How can I dynamically set what content is in each listview item without having to define a bunch of things that are IsVisible="true/false"?

ListView

answered on 21 Jun 2019

5 answers

73 views

IsInfiniteScrollingEnabled and navigation by SelectedIndex should handle wrapping animation correctly

I need to know if it's possible to change animation direction for the wrap when navigating the SlideView by SelectedIndex, so IsInfinateScrolling works with SelectedIndex navigation.

When navigating from the last element in the collection, back to the first, or from first element directly to the last by updating the Bound SelectedIndex property is there a way to reverse the animation?

When IsInfiniteScrollingEnabled="True" I believe that the animation should continue in the same direction even when you're wrapping from the last element to the first, or the first element to the last so you can have a seamless infinite navigation experience.

(the --> and <-- below are animation direction)

Current:(IsInfiniteScrollingEnabled="True")

SelectedIndex=0

SelectedIndex=1 -->

SelectedIndex=2 -->

(Last item)SelectedIndex=3 -->

SelectedIndex=0 <-- (This animation is opposite of the last several)

Desired:(IsInfiniteScrollingEnabled="True")

SelectedIndex=0
SelectedIndex=1 -->
SelectedIndex=2 -->
(Last item)SelectedIndex=3 -->
SelectedIndex=0 --> (Same direction as last animation)

Is this currently possible in the SlideView Control?

SlideView

answered on 20 Jun 2019

3 answers

153 views

Appointment Tapped on existing appointment time slot in day view

In Xamarin forms calendar day view on one hour time slot, We are unable to perform time slot tapped event when an appointment exists for that hour.

For example, If an appointment is on time 6.30 am to 7.00 am we are unable to add new appointment on time 6.00 am to 6.30 am, since the existing appointment is disabling the blank area above.

And also if one appointment exists for that whole one hour then it is occupying the whole time slot area, so there is no blank area to tapped for an new appointment on that hour.

Please help us to handle this situations.

Calendar & Scheduling

answered on 20 Jun 2019

4 answers

371 views

TreeView Template Binding - Property Not Found

Using the following;

<telerikDataControls:RadTreeView

x:Name="treeView"

Grid.Row="1"

Grid.Column="0"

Grid.ColumnSpan="3"

ItemsSource="{Binding RunList}">

<telerikDataControls:TreeViewDescriptor

DisplayMemberPath="RunStart"

TargetType="{x:Type viewModels:DriverRunVm}"

ItemsSourcePath="Jobs">

</telerikDataControls:TreeViewDescriptor>

<telerikDataControls:TreeViewDescriptor DisplayMemberPath="JobLine1" TargetType="{x:Type viewModels:JobVm}"/>

</telerikDataControls:RadTreeView>

The treeview displays the "RunStart" value in the header followed by the list of Jobs. If I change this to;

<telerikDataControls:RadTreeView

x:Name="treeView"

Grid.Row="1"

Grid.Column="0"

Grid.ColumnSpan="3"

ItemsSource="{Binding RunList}">

<telerikDataControls:TreeViewDescriptor

DisplayMemberPath="RunStart"

TargetType="{x:Type viewModels:DriverRunVm}"

ItemsSourcePath="Jobs"

ItemTemplate="{StaticResource RunHeaderTemplate}">

</telerikDataControls:TreeViewDescriptor>

<telerikDataControls:TreeViewDescriptor DisplayMemberPath="JobLine1" TargetType="{x:Type viewModels:JobVm}"/>

</telerikDataControls:RadTreeView>

And use this template;

<ContentPage.Resources>

<ResourceDictionary>

<DataTemplate x:Key="RunHeaderTemplate">

<Grid

BackgroundColor="#ffb999"

RowSpacing="0"

Padding="5,2,5,0"

Margin="0">

<Grid.RowDefinitions>

<RowDefinition Height="auto" />

</Grid.RowDefinitions>

<Grid.ColumnDefinitions>

<ColumnDefinition Width="auto" />

<ColumnDefinition Width="*" />

</Grid.ColumnDefinitions>

<Label

Grid.Row="0"

Grid.Column="0"

Text="Start:"

TextColor="{StaticResource DarkSlateGrey}"

FontSize="17"

Margin="0"

HorizontalOptions="End"

VerticalOptions="CenterAndExpand"/>

<Label

Grid.Row="0"

Grid.Column="1"

Text="{Binding RunStart}"

TextColor="{StaticResource DarkSlateGrey}"

FontSize="17"

Margin="0"

HorizontalOptions="Start"

VerticalOptions="CenterAndExpand"/>

</Grid>

</DataTemplate>

</ResourceDictionary>

</ContentPage.Resources>

The label "Start:" is displayed however the error "[0:] Binding: 'RunStart' property not found on 'Telerik.XamarinForms.DataControls.TreeView.TreeViewDataItem', target property: 'Xamarin.Forms.Label.Text'" is reported.

I have tried using "treeView:ItemText" instead of a label but I get the same error. So I don't understand how the "DisplayMemberPath" displays the start value correctly but the same property in the template doesn't work.

TreeView

answered on 20 Jun 2019

11 answers

370 views

How to use commands in datagrid?

How can I execute a job if the cell is being tapped twice? I can not find examples...

DataGrid

answered on 19 Jun 2019

4 answers

710 views

Bind ListView to Nested Collection

I am just starting with the Telerik Xamarin controls and the documentation uses a single observable collection to display and group data in the listview control. My application uses an observable collection containing the data for a driver's itinerary for multiple days which in turn contain an observable collection of jobs for each day.

Is it possible to bind the group headers to the "runs" collection and the item template to the "jobs" collection?

ListView

answered on 18 Jun 2019

2 answers

145 views

Pickers in a ListView firing ItemTemplateSelector

We are using the RadListView and have added a Picker ontrol.

When the user selects an item in the Picker, the RadListView's ItemTemplateSelector fires and reloads the cell, loosing the values.

How can we stop the ItemTemplateSelector from firing when a picker is selected?

<dataControls:RadListView
x:Name="list"
IsVisible="{Binding IsLoading, Converter={StaticResource NegateBooleanConverter}}"
ItemsSource="{Binding Items}"
BackgroundColor="White"
IsPullToRefreshActive="{Binding IsBusy}"
IsPullToRefreshEnabled="True"
SelectionMode="None">

<dataControls:RadListView.ItemTemplateSelector>

ListView

answered on 18 Jun 2019

3 answers

469 views

Colour a row of a datagrid

Hi All,

I have a data grid that is bound via itemSource my quesiton is the following how does one color a row based on a column value I would need in this example if TotalQty is less than Quantity to have it an amber color then green once they are equal. Also how does one change the font colour as well.

01.<telerikGrid:RadDataGrid x:Name="gridItemsBoms" IsVisible="False" SelectionMode="Single" SelectionChanged="GridItems_SelectionChanged" AutoGenerateColumns="False" >

02. <telerikGrid:RadDataGrid.Columns>

03. <telerikGrid:DataGridTextColumn PropertyName="SequenceNumber" HeaderText="Sequence" />

04. <telerikGrid:DataGridTextColumn PropertyName="TotalQty" HeaderText="Pick Qauntity" />

05.

06. <telerikGrid:DataGridTextColumn PropertyName="Quantity" HeaderText="Quantity" />

07. <telerikGrid:DataGridTextColumn PropertyName="Description" HeaderText="Name" />

08. <telerikGrid:DataGridTextColumn PropertyName="UnitOfMeasure" HeaderText="UnitOfMeasure" />

09.

10.

11. </telerikGrid:RadDataGrid.Columns>

12.</telerikGrid:RadDataGrid>

DataGrid

answered on 18 Jun 2019

7 answers

918 views

Button Clicked handler doesn't fire in a ListViewTemplateCell.View

Hi,

I'm trying to add a button to a RadListView cell. The ListView cell has an ItemTapped event handler, which works as expected. But when I add a button to the template cell, the button's click handler is never called.

XAML:

<telerikDataControls:RadListView x:Name="listView" ItemsSource="{Binding ListSource, Mode=TwoWay}" SelectionMode="Single" ItemTapped="List_Tapped">

<telerikDataControls:RadListView.ItemTemplate>

<DataTemplate>

<telerikListView:ListViewTemplateCell>

<telerikListView:ListViewTemplateCell.View>

<Grid>

<Grid.RowDefinitions>

<RowDefinition Height="2*" />

</Grid.RowDefinitions>

<Grid.ColumnDefinitions>

<ColumnDefinition Width="Auto" />

<ColumnDefinition Width="*" />

</Grid.ColumnDefinitions>

<Label Margin="10" Text="{Binding itemName}" Grid.Row="0" Grid.Column="0" />

<Button Text="Button" BackgroundColor="Blue" Clicked="Button_Clicked" Grid.Row="0" Grid.Column="1" Margin="0,0,30,0" HorizontalOptions="EndAndExpand" VerticalOptions="Center" />

</Grid>

</telerikListView:ListViewTemplateCell.View>

</telerikListView:ListViewTemplateCell>

</DataTemplate>

</telerikDataControls:RadListView.ItemTemplate>

</telerikDataControls:RadListView>

Code Behind:

private void List_Tapped(object sender, Telerik.XamarinForms.DataControls.ListView.ItemTapEventArgs e)

{

Debug.WriteLine("List item tapped");

}

private void Button_Clicked(object sender, EventArgs e)

{

Debug.WriteLine("Button clicked");

DisplayAlert("Alert", "Button was clicked", "OK");

}

I'm assuming that the ListView ItemTapped event is overridding the button's click handler, but how can I make this work?

Thanks in advance!

ListView

answered on 18 Jun 2019

1 answer

99 views

iOS design looks not as good as on Android

Hello all together,

I'm using the RadCartesian chart with BarSeries on Samsung Galaxy Tab with Android (9.0) and iPad with iOS (12.1) and Telerik UI for Xamarin (v2019.1.318.1). On Android the chart looks very stylish, on iOS not. On iOS the bars are not centered, thinner than on Android and the labels don't look good. How can I archive the Android look on iOS? I'm not using Telerik themes for styling.

Please have a look at "Android_chart.png" and "iOS_chart.png". The arrows 1. / 2. / 3. in iOS png show to not centered bars and the labels.

Kind regards,

Martin

Chart

answered on 17 Jun 2019