Questions on UI for Xamarin Forum

4 answers

333 views

Xamarin with VS 2019?

Like many, I spent several hours installing VS 2019 today. I decided to try the wipe/reload method and everything went well with two exceptions. I installed the Enterprise version of VS 2019 along with the Telerik & Kendo Developer tools. The control panel seems to not recognize the fact that VS2019 has Xamarin installed and thus I cannot install the Telerik UI for Xamarin toolkit. Previously, under VS 2017, I had not issues installing this package.

The second issue I encountered was odd. When uninstalling all items, via the progress control panel, the system erred on the Telerik Reporting toolkit. It seems "the account already exists" error occurred. The VS 2017 flavor uninstalled however the 2019 flavor refused. To work around the problem I was forced to do a repair then followed that with a successful uninstall. A minor inconvenience although I figured someone would like to know.

I would like to be able to install my Xamarin toolkit again.

General Discussions

answered on 11 Apr 2019

1 answer

54 views

All Day Area "All day" word translation

Hi,

Can anybody help me to do "All day" translation in calendar?

Thanks

Calendar - Xamarin.iOS

answered on 11 Apr 2019

3 answers

175 views

Day view calendar jump back to current date

hi,

when user swipe day calendar, i am fetching appointments from server in calendar DisplayDateChanged event, those server calls are under "await". This take some time to complete and then use those data to set calendar appointment source, then DisplayDateChanged event automatically fires and setting date to previously where it was. so calendar can not scroll to where user wants. This may be because of time taken to fetch data or again setting appointment source of calendar.

can reproduce using following code.

private async void daycalendar_DisplayDateChanged (object sender, Telerik.XamarinForms.Common.ValueChangedEventArgs<object> e)

{

await longrun();

}

private async Task longrun()

{

ObservableCollection<testmodel> items = new ObservableCollection<testmodel>();

for (int i = 0; i < 10; i++)

{

var item = new testmodel

{

Title = "Meeting with Tom" + i,

Detail = "Sea Garden",

StartDate = DateTime.Now,

EndDate = DateTime.Now.AddHours(1),

Color = Color.Tomato

};

items.Add(item);

}

weekcalendar.AppointmentsSource = items;

}

testmodel as is this

public class testmodel : IAppointment, INotifyPropertyChanged

tested only in Android. Any solution ?

Calendar & Scheduling

answered on 11 Apr 2019

16 answers

147 views

when do you also support the same functionalities in xamarin.android or ios as in xamarin.forms and why forms first?

Hello Telerik Support I am using Mobile apps with Xamarin and after my first app I have to write with Forms Native apps as I am more flexible there. Now I need a calendar like you already implemented it in Wpf and Asp.Net. I'm a bit sad that you offer in form more functionalities than Native (Android, IOS) will come in the future and what if and when?

Calendar - Xamarin.Android

answered on 10 Apr 2019

1 answer

234 views

Issue when scrolling a PDF

As there currently isn't a way to determine when a page changes when scrolling, I hook into the PropertyChanged event of the RadPdfViewer and check the VisiblePagesStartIndex property, however when scrolling to the last page of the PDF the VisiblePagesStartIndex does not match, for example, I have a 10 page PDF document and when I scroll all the way to the bottom, the last VisiblePagesStartIndex property change is 8, when it should be 9. If I then invoke the NavigateToNextPageCommand then the VisiblePagesStartIndex property changes to the expected value of 9, although I am already at the bottom of the document.

In effect I need to know when I reach the end of the PDF so that I can update my own UI buttons to reflect the current position in the document, for example, disabling the down button when I can no longer navigate to a next page. I can achieve this when using the NavigateToNextPageCommand and NavigateToPreviousPageCommand method of document navigation but not when scrolling.

I have tried a work around where if the VisiblePagesStartIndex is 8 then invoke the NavigateToNextPageCommand but this doesn't work when scrolling back up the document.

PdfViewer

answered on 10 Apr 2019

3 answers

155 views

Invoking commands from code behind

I would like to invoke the NavigateToNextPageCommand, NavigateToPreviousPageCommand and NavigateToPageCommand commands from code behind however I am having a bit of trouble.

I have successfully invoked the NavigateToNextPageCommand using the following code :-

if (PdfViewerControl2.NavigateToNextPageCommand.CanExecute(null))
{

PdfViewerControl2.NavigateToNextPageCommand.Execute(null);

CurrentPageNumber++;

SetCanExecutes(BindingContext as SmartDocViewModel);
}

However, using a similar approach for the NavigateToPreviousPageCommand, the CanExecute method against the command returns false.

Also I am trying to invoke the NavigateToPageCommand in such a way that it acts as a beginning/end command, so I pass either 1 or the VisiblePagesCount value (last page) to the NavigateToPageCommand command however it does not change the page.

The provided sample uses the commands directly via buttons in the XAML however due to my use case I need to invoke the commands in code behind.

Would you be able to help me?

PdfViewer

answered on 10 Apr 2019

1 answer

247 views

How to style RadListView with rounded corners

I have a RadListView with a Grid Layout (see snippet below).

This does round the corners as expected, however, there is white space surrounding the items that the missing corners reveal. Is there a way to remove this white background?

Screenshot of behavior

<Grid Padding="50,0,25,0">

<telerikDataControls:RadListView x:Name="agendaListView"

ItemsSource="{Binding AgendaItems}"

IsLoadOnDemandEnabled="{Binding ReachedAgendaEnd, Converter={StaticResource ReverseBooleanConverter}}"

IsLoadOnDemandActive="{Binding IsLoadOnDemandActive}"

LoadOnDemandBufferItemsCount="50"

LoadOnDemandMode="Automatic"

BackgroundColor="#f6f6f8"

IsVisible="{Binding IsFirstLoad, Converter={StaticResource ReverseBooleanConverter}}">

<telerikDataControls:RadListView.ItemTemplate>

<DataTemplate>

<telerikListView:ListViewTemplateCell>

<telerikListView:ListViewTemplateCell.View>

<Frame CornerRadius="10" Padding="0" IsClippedToBounds="True" HasShadow="True">

<Grid ColumnSpacing="0">

<Grid.ColumnDefinitions>

<ColumnDefinition Width="100" />

<ColumnDefinition Width="*" />

</Grid.ColumnDefinitions>

<StackLayout Grid.Column="0" BackgroundColor="#00AEFF">

<StackLayout Orientation="Horizontal" HorizontalOptions="CenterAndExpand"

Padding="0,25,0,0">

<Label Text="{Binding DayNumber}" HorizontalTextAlignment="Center"

FontSize="48" TextColor="White" FontAttributes="Bold"></Label>

</StackLayout>

<StackLayout Orientation="Horizontal" HorizontalOptions="CenterAndExpand">

<Label Text="{Binding DayWord}" HorizontalTextAlignment="Center"

FontSize="16" TextColor="White"></Label>

</StackLayout>

<StackLayout Orientation="Horizontal" HorizontalOptions="CenterAndExpand">

<Label Text="{Binding DateMonthYear}" HorizontalTextAlignment="Center"

FontSize="10" TextColor="White"></Label>

</StackLayout>

<StackLayout Grid.Column="1" BackgroundColor="#fcfcfc">

<StackLayout Orientation="Horizontal"

HorizontalOptions="CenterAndExpand"

VerticalOptions="CenterAndExpand"

Padding="5,0,5,0">

<Label Text="{Binding Title}" LineBreakMode="WordWrap" HorizontalTextAlignment="Center"

TextColor="#505259"></Label>

</StackLayout>

</Grid>

</Frame>

</telerikListView:ListViewTemplateCell.View>

</telerikListView:ListViewTemplateCell>

</DataTemplate>

</telerikDataControls:RadListView.ItemTemplate>

<telerikDataControls:RadListView.Commands>

<telerikListViewCommands:ListViewUserCommand Id="ItemTap" Command="{Binding AgendaDetailCommand}" />

<telerikListViewCommands:ListViewUserCommand Id="LoadOnDemand" Command="{Binding AgendaLoadOnDemandCommand}" />

</telerikDataControls:RadListView.Commands>

<telerikDataControls:RadListView.LayoutDefinition>

<telerikListView:ListViewGridLayout

ItemLength="150"

SpanCount="2"

HorizontalItemSpacing="30"

VerticalItemSpacing="30" />

</telerikDataControls:RadListView.LayoutDefinition>

</telerikDataControls:RadListView>

</Grid>

ListView

answered on 10 Apr 2019

3 answers

148 views

Line chart does not respond to background color

Hello all,

I'm trying to set the background color of my line chart (RadCartesianChart). This is the code that i'm using:

```

var chart = new RadCartesianChart
            {
                BackgroundColor = Color.Black,
                VerticalOptions = LayoutOptions.FillAndExpand,
                HorizontalOptions = LayoutOptions.Fill,
                HeightRequest = Device.RuntimePlatform == Device.Android ? 200 : 250,
                HorizontalAxis = new CategoricalAxis
                {
                    LabelTextColor = AppResources.Get<Color>("TextColor"),
                    LabelFontSize = 10,
                    LabelFitMode = AxisLabelFitMode.Rotate,
                    LabelFormatter = new HorizontalAxisLabelFormatter()
                },
                VerticalAxis = new NumericalAxis
                {
                    LabelTextColor = AppResources.Get<Color>("TextColor"),
                    LabelFontSize = 10,
                    LabelFormatter = new VerticalAxisLabelFormatter()
                },
            };

```

However, when i run this in the iOS simulator, the result is as follows (see attachment).

The background color stays white. The labels do go white, but the chart itself does not.

When i try to do this with a bar chart, it does work. On Android the chart also has a black background color.

Does anybody know what I am missing?

Thanks in advance,

Reense

General Discussions

answered on 10 Apr 2019

5 answers

177 views

RadPieChart - Programmatic selection

Hi there,

I am looking for a way to select a slice of the piechart from code-behind. I have have looked into the chart and series properties but found no selectable datapoints property. The chartSelectionBehavior offers a ClearSelection method and the readonly SelectedPoints property, but nothing to add a selected point.

Is there any possibility to add a selected slice from code-behind?

Regards,

Michael

Chart

answered on 09 Apr 2019

1 answer

222 views

NumericInput inside Listview with other input elements

In Xamarin Forms, I have seen issues when you place this RadNumericInput input element inside of a ListView's ViewCell with other input elements, such as a Entry field. Only the first element added will honor the input listeners and respond accordingly. When pressing the second, in this case the numeric input, the keyboard pops up but cannot maintain it's focus inputs, vacillating between opening and closing the keyboard uncontrollably.

"finishComposingText on inactive InputConnection" is called and processed continually.

Could you offer any solutions to this issue?

Thank you

Jason

NumericInput

answered on 09 Apr 2019