how to Fill Image fullscreen in stackLayout in Xamarin ?

I can't set Image in fit to stacklayout

.XAML File 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="Test.FirstLoadScreen" >

  <StackLayout Padding="0" BackgroundColor="Yellow">
    <Image Source="ic_splash.png" HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand" > </Image>
  </StackLayout>
</ContentPage>

Screenshot of Output Android and Window Phone....

I want to fit Image in Background.

Hello,

i have a problem with the class "UIAlertView". I have a Xamarin.Forms project. UIAlertView is working fine in iOS. If i switch to my android project he starts directly complaining about the "UIKit" using. This was working fine a while ago. After an Xamarin update Xamarin is now saying the it is not able to find UIKIT. The method below is working in iOS but not in android anymore.


async static Task ShowAlert(string title, string btnName)
{
var alert = new UIAlertView ();
alert.Title = title;
alert.AlertViewStyle = UIAlertViewStyle.PlainTextInput;

        var tcs = new TaskCompletionSource<nint> ();

        alert.AddButton (btnName);
        alert.Clicked += (s, e) => tcs.SetResult (e.ButtonIndex);
        alert.Show ();

        await tcs.Task;

        return alert.GetTextField (0).Text;
    }

Can someone help me ? ( In iOS it is working fine )

Regards
C64Gamer

Hi Community

I have searched for a while now and did not find something. Is there a control/plugin out there for a cross-platform floating action button?
I know, how to implement it for my Android Projects (and I also know about the nuget packages for it).

But I want a FAB for all platforms (Android, iOS and UWP). But my knowhow to do a custom renderer is to bad...

thanks

I am trying to implement a master detail page with tabs on top, which repopulate a listview. It works, but, afteryou click on 5 or 6 tabs you get an out of memory exception.

My Main Page:

public partial class RootPage : MasterDetailPage
{

    MenuPage menuPage;

    public RootPage()
    {
        menuPage = new MenuPage();

        menuPage.Menu.ItemSelected += (sender, e) => NavigateTo(e.SelectedItem as MenuItem);


        Master = menuPage;
        Master.BackgroundColor = Color.White;

        Detail = new TabsPage(menuPage.Menu.SelectedItem as MenuItem);
        Detail.BackgroundColor = Color.White;
    }

    void NavigateTo(MenuItem menu)
    {

        Detail = new TabsPage(menu);

        IsPresented = false;
    }
}

My Tabbed Page:

public class TabsPage : TabbedPage
{


    public TabsPage(MenuItem item)
    {


        //pass category id
        var dates = new Database().GetCategoryDates(item.ID);


            this.Children.Add(new EventPage(null, item.ID) { Title = "All" });

        foreach (var date in dates)
        {
            this.Children.Add(new EventPage(date,item.ID) {  Title =  date.Date.ToString("M/d") });
        }


    }

}

My Event Page:

public class EventPage : ContentPage
{


    public EventPage(DateTime? date, int catID)
    {


        List<Group> events = new Database().GetEvents(date, catID);

        var cell = new DataTemplate(typeof(EventCell));

        var template = new DataTemplate(typeof(CustomHeaderCell));

        this.Content = new ListView()
        {
            IsGroupingEnabled = true,
            GroupDisplayBinding = new Binding("Name"),
            GroupShortNameBinding = new Binding("Name"),
            GroupHeaderTemplate = template,

            HasUnevenRows = true,
            ItemsSource = events,
            VerticalOptions = LayoutOptions.FillAndExpand,
            BackgroundColor = Color.White,
            ItemTemplate = cell,
            SeparatorColor = Color.FromHex("#ddd"),
            Footer = new Image() { Source = "brewtownlogo.png", HeightRequest = 50.0 }
        };


    }

}

Hi,

I have multiple tabs in my app i need to switch the programmatically by tab index and with page name. because for 3 tabs i have a single page and rest having different pages. these things i need to do in my Model.

Due to version conflict I did Uninstall and then Reinstall all of the NuGet Packages in .Droid and Portable project accordingly.
The version conflict error is gone but get 1 error :
[
The "Javac" task failed unexpectedly. System.UnauthorizedAccessException: Access to the path 'C:\Users\a585113\Documents\Visual Studio 2015\Projects\WeatherApp4\WeatherApp4\WeatherApp4.Droid\obj\Debug\android\src\mono\android\support\v7\internal' is denied.
at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
at System.IO.FileSystemEnumerableIterator

1.AddSearchableDirsToStack(SearchData localSearchData)
at System.IO.FileSystemEnumerableIterator

How to resolve it?

Attached The Screen shot below, click on icon to check.

I have simple forms project with single Android project in the solution. I Updated both to the most up to date stable nuget packages but when I try to fetch an Image from a file in Android I get
this nasty exception:
System.MissingMethodException: Method 'Looper.get_IsCurrentThread' not found.****

according to the forums, Xamarin has "fixed" it so how come I still get this exception.

Hi,
i couldn´t find instructions how to insert the UWP AdMediator into Xamarin.Forms, so I used this way:

        RowDefinition gridLineAd;
        UC.AdMedUC adMedUC;
        Microsoft.AdMediator.Universal.AdMediatorControl myAdMediator;
        Grid adWrapper;
        Button btnRemoveAd;

        public MainPage()
        {
            this.InitializeComponent();

            LoadApplication(new TeamOrgaXF.App());


            Grid grid = new Grid();
            grid.RowDefinitions.Add(new RowDefinition() { Height = new GridLength(1, GridUnitType.Star) });

            gridLineAd = new RowDefinition() { Height = new GridLength(290, GridUnitType.Pixel) };
            grid.RowDefinitions.Add(gridLineAd);

            //XF APP
            var can = this.Content as Canvas;
            this.Content = null;
            grid.Children.Add(can);

            //Wrapper Ad
            adWrapper = new Grid();
            adWrapper.RowDefinitions.Add(new RowDefinition() { Height = new GridLength(30, GridUnitType.Pixel) });
            adWrapper.RowDefinitions.Add(new RowDefinition() { Height = new GridLength(1, GridUnitType.Star) });

            btnRemoveAd = new Button();
            btnRemoveAd.Content = "Remove advertising";
            btnRemoveAd.Tapped += BtnRemoveAd_Tapped;
            adWrapper.Children.Add(btnRemoveAd);

            adMedUC = new UC.AdMedUC();
            myAdMediator = adMedUC.myAdMediator;
            Grid.SetRow(adMedUC, 1);
            adWrapper.Children.Add(adMedUC);

            Grid.SetRow(adWrapper, 1);
            grid.Children.Add(adWrapper);


            this.Content = grid;

            adSize();
            noAd();
        }

Will it cause problems?

Best regards,
Thomas

I'm coming today because I'm stuck on an error. I just can't find the difference between the tutorial I'm following and my project.

[System.CodeDom.Compiler.GeneratedCodeAttribute("Xamarin.Forms.Build.Tasks.XamlG", "0.0.0.0")]
private void InitializeComponent() {
    this.LoadFromXaml(typeof(AppPageSwitcher));
    Client = this.FindByName<global::Xamarin.Forms.Button>("Client");
}

Like mentioned in the tutorial, I've created a new Blank App (Xamarin.Forms Portable). Then, I've deleted the UWP part and the Win 8.1 as well. So I still have the reste (Portable/Android/iOS/WinPhone 8.1). It's also says to install and update several packages and everything is done for me.

So, they propose to create three class about their project, me I only created one which is related to TCP client connection. (TCPclient.cs)

PS: TCPclient.cs: I can't put the code because I'm trying to test it to make it works. That's why I need to create a graphic app.

Begin writing shared UI code

I'm at this step (I know, it's not far in the tutorial). They tell us to "Add a Forms Xaml Page named WeatherPage.cs by right-clicking the WeatherApp project and selecting Add > New Item....". I do it and create a first xaml page AppPageSwitcher.xaml. This page is just a test of desing from xaml.

<?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="PROJECT_NAME.Controlers.AppPageSwitcher">
         <Button x:Name="Client" Content="Client"/>
</ContentPage>

So now, I made this code because I just want to try something easier

public partial class AppPageSwitcher : ContentPage
{
    public AppPageSwitcher()
    {
        InitializeComponent();
        this.Title = "PROJCET_NAME";
        Client.Clicked += ClientButton_Clicked;
    }

    private void ClientButton_Clicked(object sender, EventArgs e)
    {
        Client.Text = this.Title;
    }
}

And the issue appears:

this.LoadFromXaml(typeof(AppPageSwitcher));

I checked again and again, I tried to do the tutorial by creating the same project but without The weather key and... The button is present.. Where can be the difference? Moreover, I have a MaPage.xaml.cs that I've wrote like that:

<ContentPage.Content>
    <local:CustomMap x:Name="customMap"/>
</ContentPage.Content>

I used <ContentPage.Content> unlike this tutorial and it worked. When I tried to add it, it didn't works.

It's so boring to get all of the time lot of errors like that.. Maybe it's easy to solves, but from hours, I'm stuck. If anyone can help, thank !

This might have been discussed already; but I only found 1 discussion and it didn't answer the question. As an aside, it would be nice to be able to limit my searches to a single forum.

I am trying to get my Master/Detail app to support iOS 6. I am seeing two major issues...

1. When a new NavigationPage is made the Detail page, there are 20 white pixels between the status bar and the navigation bar.
2. After pushing a page onto a navigation stack, there is no back button. GetHasBackButton returns true. SetBackButtoinTitle makes no difference.

Looking at the source code for Xamarin.Forms, it looks like there is code in some places to support iOS versions less than 7.

Is iOS 6 supported? Am I wasting my time trying to get it to work? (I know some users of my app will be on devices with iOS 6).

I have visual studio 2015 community installed on windows 10. I'm getting an error 'ContentPage was not found' after i do the follow simple steps.

• In Visual Studio 2015 add new project select 'Blank app (xamarin.forms portable)'
• then i update Xamarin forms nuget package to the latest stable build
• then i add a new file 'Forms Xaml Page'
• then build the app

Now there are 2 errors (for each item on the xaml page, a contentpage and a label) both related to the controls not being found. This is the first.

• The type 'ContentPage' was not found. Verify that you are not missing an assembly reference and that all referenced assemblies have been built.

I've tried reinstalling Xamarin, and repaired Visual studio. I'm a bit lost, and would really appreciate any pointers.

I have use below 2 labels on xamarin forms xaml.

<Label FontAttributes="Bold" WidthRequest="100">
                            <Label.Text>Ship From:</Label.Text>
                          </Label>

<Label Text="Ship From: " />
<Label Text="Expected Delivery Date: " />

But on iOS simulator I see text as below.
=> Expected Delivery
=> Ship

Expected outcome should be,
=> Expected Delivery Date:
=> Ship From:

I did not get the reason why "Date:" and "From:" are missing.

Hello

I want to create my own Imgur uploader with Xamarin.Forms MVVM.

But i have an issue when i want to convert my image in base64 to upload in the url.

I have this error:

Uri is longer than the maximum 32766 characters.

And yes, look my byte

I made this code to try to fix it but not working

private string ImageToBase64(Stream stream)
        {
            var memoryStream = new MemoryStream();
            stream.CopyTo(memoryStream);
            var result = memoryStream.ToArray();

            var base64img = Convert.ToBase64String(result);

            StringBuilder sb = new StringBuilder();

            for (int i = 0; i < base64img.Length; i += 32766)
            {
                sb.Append(Uri.EscapeDataString(base64img.Substring(i, Math.Min(32766, base64img.Length - i))));
            }

            return sb.ToString();
        }



    public async Task<ImgurImage> UploadImageAnonymous(Stream imageStream)
            {
                using (HttpClient client = new HttpClient())
                {
                    SetHeaders(client);

                    string base64Image = ImageToBase64(imageStream);

                    var formContent = new FormUrlEncodedContent(new[] {
                        new KeyValuePair<string, string>("image", base64Image)
                    });
                    HttpResponseMessage response = await client.PostAsync(new Uri(BaseUrl + "upload"), formContent);
                    await CheckHttpStatusCode(response);
                    string content = await response.Content.ReadAsStringAsync();

                    ImgurRootObject<ImgurImage> imgRoot = JsonConvert.DeserializeObject<ImgurRootObject<ImgurImage>>(content);

                    return imgRoot.Data;
                }
            }

Can you help me ?

When I add a ToolbarItem to a ContentPage inside a TabbedPage (which is also contained in a NavigationPage), the Title is hidden/removed. If I don't add the ToolbarItem, the Title is visible. There is also a Back button.

Anyone come across this or know if I'm doing something wrong?

Thanks!

I am trying to run the following statement (using PCL Storage package):

IFile destPhotoFile = await rootFolder.CreateFileAsync(copy2Filename, CreationCollisionOption.ReplaceExisting);

I get the following error:

Access is denied. (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED))

I also checked the following permissions using Plugin.Permissions. Both the permissions are 'Granted'.

Plugin.Permissions.Abstractions.PermissionStatus photosPermissionStatus
    = await Plugin.Permissions.CrossPermissions.Current.CheckPermissionStatusAsync(Plugin.Permissions.Abstractions.Permission.Photos);
Plugin.Permissions.Abstractions.PermissionStatus storagePermissionStatus
    = await Plugin.Permissions.CrossPermissions.Current.CheckPermissionStatusAsync(Plugin.Permissions.Abstractions.Permission.Storage);

Hi all,

I am new here and I am trying to create a shared app in Visual Studio 2015 (in fact I will only release it for WP8.1, it's just to prove).
My problem is that, if I use a ListView with inside a label and a switch, only the first element of the view shows the switch. My example is based on the official repository, "Todo".

App1/Shared/View/SharedMainPage.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Windows.UI.Xaml.Media;
using Xamarin.Forms;

namespace App1.Shared.View
{
class SharedMainPage : ContentPage
{
ListView list;

    public SharedMainPage()
    {
        Title = "Einkaufen";
        NavigationPage.SetHasNavigationBar(this, true);
        BackgroundColor = Color.FromHex("23282D");
        list = new ListView
        {
            RowHeight = 90,
            ItemTemplate = new DataTemplate(typeof(SingleShopElementCell))
        };

        // These commented-out lines were used to test the list prior to integrating the database
        list.ItemsSource = new ShopElement[] {
            new ShopElement {Name = "Buy pears", Bought = true },
            new ShopElement {Name = "Buy oranges", Bought = true},
            new ShopElement {Name = "Buy mangos", Bought = false},
            new ShopElement {Name = "Buy apples", Bought = false},
            new ShopElement {Name = "Buy bananas", Bought = true}
        };

        var layout = new StackLayout();
        layout.Children.Add(list);
        layout.VerticalOptions = LayoutOptions.FillAndExpand;
        Content = layout;
    }

    protected override void OnAppearing()
    {
        base.OnAppearing();
    }

}

}

And this is App1/Shared/View/SingleShopElementCell.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Windows.UI.Xaml.Controls;
using Xamarin.Forms;

namespace App1.Shared.View
{
class SingleShopElementCell : ViewCell
{
public SingleShopElementCell()
{
var label = new Label
{
VerticalTextAlignment = TextAlignment.Center,
HorizontalOptions = LayoutOptions.StartAndExpand,
FontSize = 21,
TextColor = Color.White
};
label.SetBinding(Label.TextProperty, "Name");

        var check = new Switch();
        check.SetBinding(Switch.IsToggledProperty, "Bought");
        check.IsVisible = true;

        var layout = new StackLayout
        {
            Padding = new Thickness(20),
            Orientation = StackOrientation.Horizontal,
            HorizontalOptions = LayoutOptions.StartAndExpand,
            Children = { label, check }
        };

        View = layout;
    }
}

}

Finally this is the ShopElement.cs class:

using Xamarin.Forms;

namespace App1.Shared
{
class ShopElement
{
public String Name { get; set; }
public bool Bought { get; set; }
public short ID { get; }

    public ShopElement() { }

    public ShopElement(String name)
    {
        this.Name = name;
    }
}

}

Hope you can help me, since it is a day that I am trying to solve this strange problem (I did many proofs). Thanks!

Hi all,
Just wanted to gather some opinions and advice. I am designing a ViewCell with a format that will be replicated in many ways in my app and I want to make sure I'm choosing the best layout for different screen sizes, test sizes, binding etc.

Right now, I am using the RelativeLayout and it is working pretty well. However, I'm running into an issue using the FontAwesome font with it where unbinded labels (location icon and clock icon) are being placed in the ListView ViewCell at contraints BEFORE the entire ViewCell & ListView are populated with data, and thus are not being redrawn when the cell populates with bound data. The other labels are all working beautifully, but it is because these are redrawn (I think) at the time of binding and their constraints are being updated. If anyone could offer advice on how to force redraw/recompute the constraints, that would be awesome.

Additionally, I want labels with a lot of text to wordwrap and THEN truncate the tail once the bottom of the Viewcell is reached. But with relativelayout, it appears as though the longer labels are being truncated at the tail and head.

I just don't have that much faith in RelativeLayout going forward so I want to get some advice....I would think StackLayout would be pretty good for what I'm trying to do (see Screenshot)

Hi there. I'm studying Xamarin.Forms (on Visual Studio), so I create a lot of demo projects, however I only need Android and iOS projects. But because Xamarin also adds Windows, WinPhone and UWP to the project, Visual Studio takes a lot of time to create new projects. Is there a way to tell Xamarin to only add Android and iOS projects when creating a new Xamarin.Forms project?

I am facing some issue while binding collection to ListView's custom ViewCell. Collection has deep hierarchy.

Models

public class ViewModel : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;

    private ObservableCollection<ParentViewModel> parentList;

    public ObservableCollection<ParentViewModel> ParentList
    {
        get
        {
            return parentList;
        }
        set
        {
            if (parentList != value)
            {
                parentList = value;

                if (PropertyChanged != null)
                {
                    PropertyChanged(this,
                        new PropertyChangedEventArgs("ParentList"));
                }
            }
        }
    }
}

public class ParentViewModel : INotifyPropertyChanged
{
    private ObservableCollection<ChildViewModel> myProperty;

    public ObservableCollection<ChildViewModel> MyProperty
    {
        get
        {
            return myProperty;
        }
        set
        {
            if (myProperty != value)
            {
                myProperty = value;

                if (PropertyChanged != null)
                {
                    PropertyChanged(this,
                        new PropertyChangedEventArgs("MyProperty"));
                }
            }
        }
    }

    public event PropertyChangedEventHandler PropertyChanged;
}

public class ChildViewModel : INotifyPropertyChanged
{
    private string prop1;
    private string prop2;

    public string Prop1
    {
        get
        {
            return prop1;
        }
        set
        {
            if (prop1 != value)
            {
                prop1 = value;

                if (PropertyChanged != null)
                {
                    PropertyChanged(this,
                        new PropertyChangedEventArgs("Prop1"));
                }
            }
        }
    }
    public string Prop2
    {
        get
        {
            return prop2;
        }
        set
        {
            if (prop2 != value)
            {
                prop2 = value;

                if (PropertyChanged != null)
                {
                    PropertyChanged(this,
                        new PropertyChangedEventArgs("Prop2"));
                }
            }
        }
    }

    public event PropertyChangedEventHandler PropertyChanged;
}

Here is ViewModel creation logic and bindingcontext

ChildViewModel objChildViewModel1 = new ChildViewModel { Prop1 = "Prop1", Prop2 = "Prop2" };
        ChildViewModel objChildViewModel2 = new ChildViewModel { Prop1 = "Prop1", Prop2 = "Prop2" };

        ParentViewModel objParentViewModel1 = new ParentViewModel();
        objParentViewModel1.MyProperty = new ObservableCollection<ChildViewModel> { objChildViewModel1, objChildViewModel2 };

        ParentViewModel objParentViewModel2 = new ParentViewModel();
        objParentViewModel2.MyProperty = new ObservableCollection<ChildViewModel> { objChildViewModel1, objChildViewModel2 };

        ViewModel obj = new ViewModel
        {
            ParentList = new ObservableCollection<ParentViewModel> { objParentViewModel1, objParentViewModel2 }
        };

        //set binding context
        this.BindingContext = obj;

List View in Xaml

        <ListView x:Name="lstView" ItemsSource="{Binding ParentList}">
        </ListView>

List View in C#

 lstView.ItemTemplate = new DataTemplate(() =>
        {
            var cell = new ViewCell();
            var grid1 = new Grid();
            grid1.RowDefinitions.Add(new RowDefinition { Height = new GridLength(1, GridUnitType.Star) });
            grid1.RowDefinitions.Add(new RowDefinition { Height = new GridLength(1, GridUnitType.Star) });
            grid1.ColumnDefinitions.Add(new ColumnDefinition { Width = new GridLength(1, GridUnitType.Star) });
            grid1.ColumnDefinitions.Add(new ColumnDefinition { Width = new GridLength(1, GridUnitType.Star) });

            //I am using static count variable  as below to access collection item
            //Is there any way I can access a collection item for which this DataTemplate called  ????
            //It will be called equals to number of items in collection bound to listView**
            for (int i = 0; i < obj.ParentList[count].MyProperty.Count; i++)
            {

                var Label11 = new Label { };

               //how to databind obj.MyProperty[0].Prop1 to Label1 ? Did my implementation is correct ?????
                Label1.SetBinding(Label.TextProperty, "ParentList[" + count.ToString() + "].MyProperty[" + i.ToString() +"].Prop1");

                var Entry11 = new Entry { };

                //how to databind obj.MyProperty[0].Prop2 to Entry1 ? Did my implementation is correct ?????
                Entry1.SetBinding(Entry.TextProperty, "ParentList[" + count.ToString() + "].MyProperty[" + i.ToString() + "].Prop2");

                grid.Children.Add(Label11, 0, 0 + i);
                grid.Children.Add(Entry11, 1, 0 + i);

            }

            count++;

            cell.View = grid1;
            return cell;
        });

The requirement is to have to show childrenlist data per parentListItem. So, one ListView Row would have multiple child row which I have tried to implement using grids in ViewCell of List View as I have shown in the code.

Questions,

1. Did I correctly data bind viewmodel with label and entry view/control as I am not getting data binded on screen.
2. ItemTemplate for List would be created for each viewmodel (in this case parentmodel) in collection. So, is there any way I can get that viewModel for which ItemTemplate has been created?

I just upgraded to Xamarin Studio 5.9.7 (build 9) and rebuilt my xamarin forms iOS app and it's size grew from 17MB to 41MB. Has anyone else observed similar behavior? The app store version grew from 50 to 150MB! I also updated my nu get packages as well.

Also getting Foundation.MonoTouchException when trying to run code in simulator.
Foundation.MonoTouchException: Objective-C exception thrown. Name: NSInternalInconsistencyException Reason: Application windows are expected to have a root view controller at the end of application launch