my question is, could I Binding string image to image source ? I have multiple image and the image will change on if condition. So:
Xaml on Xamarin forms:
<Image Source="{Binding someImage}" Aspect="Fill" Grid.Row="2"></Image>
Codebehind c#
public String someImage;
public String SomeImage
{
set
{
if (someImage != value)
{
someImage = value;
}
}
get
{
return someImage;
}
}
InitializeComponent part:
if(true)
{
someImage = "backgroundListViewGren.png";
}
else
{
someImage = "backgroundListViewRed.png";
}
the image is in "Images" folder on portable project
but this, doesn't work, maybe i wront something but I don't understand. Any solutions ?
I've tried with ImageSource and not string, but don't work too.
I'll post this answer here because it's the one I was looking for and I suspect most others are (and Google currently directs you here, which currently isn't super helpful).
How to bind an image using XAML:
XAML:
<Image>
<Image.Source>
<FileImageSource File="{Binding SomeImage}" />
</Image.Source>
</Image>
Then in the ViewModel, C#:
public string SomeImage
{
get { return string.Format("prefix-{0}-suffix.png", OtherProperty); }
}
Newer, better, but essentially equivalent c# you can use instead of the above:
public string SomeImage => $"prefix-{OtherProperty}-suffix.png";
This is certainly the easiest way to set it up, IMO :).
EDIT: It should go without saying, but the image should obviously be in the Resources folder of the project for each platform.
EDIT2, much later: In case it's not obvious, "prefix", "suffix" are just random strings, SomeImage just has to return the path of your image. SomeImage and OtherProperty are members of your view model class, OtherProperty is just something you're basing your image name on (because if you know the whole name in advance, you don't need this question).
You said:
the image is in "Images" folder on portable project
Each platform have a different approach for resources and images. Xamarin handles that in every platform for example Xamarin.iOS has embedded resource while Xamarin.Android uses Android resource for images.
You should place your images in every project for Xamarin.Forms to know where to look for them in each platform.
For more information look at this.
For using images from the PCL, check out this part in the Xamarin documentation.
You should make sure the Build action for each image is set to Embedded Resource.
Then, if you want to use them in XAML, specify a MarkupExtension
[ContentProperty ("Source")]
public class ImageResourceExtension : IMarkupExtension
{
public string Source { get; set; }
public object ProvideValue (IServiceProvider serviceProvider)
{
if (Source == null)
{
return null;
}
// Do your translation lookup here, using whatever method you require
var imageSource = ImageSource.FromResource(Source);
return imageSource;
}
}
You should then be able to use your images like this.
<?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:local="clr-namespace:WorkingWithImages;assembly=WorkingWithImages"
x:Class="WorkingWithImages.EmbeddedImagesXaml">
<StackLayout VerticalOptions="Center" HorizontalOptions="Center">
<!-- use a custom Markup Extension -->
<Image Source="{local:ImageResource WorkingWithImages.beach.jpg}" />
</StackLayout>
</ContentPage>
Like mentioned in the comments, if you want this to work out of the box place them in the Resources folder of your respective platform project. This way you can also leverage the auto sizing mechanisms that are in place. To read more on this method see this page.
By adding them with the right naming convention in the right folder, you can simply refer to the filename and Xamarin.Forms will translate that to the right format for the platform.