felipebaltazar

<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:local="clr-namespace:TeuNamespace.ateapastadosconverters"
             x:Class="TeuNamespace.TuaPage">
    <!---Aqui vc registra um singleton do conversor e da uma chave pra usar ele no xaml--->         
    <ContentPage.Resources>
        <ResourceDictionary>
            <local:ByteToImageSource x:Key="byteToImgSource" />
        </ResourceDictionary>
    </ContentPage.Resources>

felipebaltazar

public class ByteToImageSourceConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return ImageSource.FromStream(() => new MemoryStream((byte[])value));;
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return null;

felipebaltazar

    public class MovieViewModel : BaseViewModel
    {

        private string name = string.Empty;
        private string image = string.Empty;
        
        public string Name
        {
            get => name;
            set => SetProperty(ref name, value);

felipebaltazar

<Label Text="{Binding Name}"
       HorizontalOptions="FillAndExpand"
       VerticalOptions="FillAndExpand"
       TextColor="White"/>

<Image HorizontalOptions="FillAndExpand"
       VerticalOptions="FillAndExpand"
       Aspect="AspectFill"
       Source="{Binding Path=Image}" />

felipebaltazar

namespace Xamarin.Theming.Droid
{
    [Activity(Label = "Xamarin.Theming", Icon = "@mipmap/icon", Theme = "@style/MainTheme", MainLauncher = true,
        ConfigurationChanges = ConfigChanges.ScreenSize | ConfigChanges.Orientation | ConfigChanges.UiMode)]
    public class MainActivity : global::Xamarin.Forms.Platform.Android.FormsAppCompatActivity
    {
        protected override void OnCreate(Bundle savedInstanceState)
        {
            TabLayoutResource = Resource.Layout.Tabbar;
            ToolbarResource = Resource.Layout.Toolbar;

felipebaltazar

        private const float DEFAULT_SIGMA = -6f;
        internal static SKImageFilter ToSKDropShadow(this Color shadowColor, float distance)
        {
            return SKImageFilter.CreateDropShadow(
                    distance,
                    distance,
                    DEFAULT_SIGMA,
                    DEFAULT_SIGMA,
                    shadowColor.ToSKColor(),
                    SKDropShadowImageFilterShadowMode.DrawShadowOnly);

felipebaltazar

 protected override void DrawControl(SKPaint paint, SKPaintSurfaceEventArgs args)
        {
            var info = args.Info;
            var surface = args.Surface;
            var canvas = surface.Canvas;

            var fShadowBlur = Convert.ToSingle(ShadowBlur);
            var padding = fShadowBlur * 3f;
            var diameter = padding * 2;
            var retangleWidth = info.Width - diameter;

felipebaltazar

<ListView ItemsSource="{Binding ListaDeOpcoes}" local:ItemTappedAttached.Command="{Binding OpcaoSelecionadaCommand}>

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public class ItemTappedAttached
 {
        public static readonly BindableProperty CommandProperty =
        BindableProperty.CreateAttached (
            propertyName: "Command",
            returnType: typeof(ICommand),
            declaringType: typeof(ListView),
            defaultValue: null,
            defaultBindingMode: BindingMode.OneWay,
            validateValue: null,

felipebaltazar

public sealed class MyViewModel : BaseViewModel
{
...

     public MyViewModel()
     {
          MessagingCenter.Subscribe<NavigationEventArgs>(this, nameof(Page.OnAppearing), OnAppearing);
          MessagingCenter.Subscribe<NavigationEventArgs>(this, nameof(Page.OnDisappearing), OnDisappearing);
     }