How to convert the contents in the Stacklayout to Pdf or png form in Xamarin forms-CodePudding

I want convert the contents in the StackLayout to .png or .pdf format and need to print the same from my iOS device. And my printer will support only image and pdf. How can I achieve this in xamarin forms.Please help me. Here is my Xaml.

<StackLayout HorizontalOptions="FillAndExpand" Padding="20" VerticalOptions="CenterAndExpand">
        <Frame HasShadow="False" BorderColor="LightGray"
               CornerRadius="0" VerticalOptions="Center"
               HorizontalOptions="Center">
            <StackLayout HorizontalOptions="Center" Spacing="30">
                <Label HorizontalTextAlignment="Center">
                 <Label.FormattedText>
                     <FormattedString>
                         <Span Text="ID : " FontAttributes="Bold"
                               TextColor="Black"/>
                         <Span Text="1234" TextColor="Green" FontAttributes="Bold"/>
                     </FormattedString>
                 </Label.FormattedText>
                </Label>
                <Frame CornerRadius="1" BorderColor="Green"
                       HasShadow="False" WidthRequest="40" HorizontalOptions="Center">
                    <Image Source="ProfileImg" HeightRequest="70"
                           WidthRequest="50"/>
                </Frame>
                <Label Text="Xamarin" HorizontalTextAlignment="Center"
                       FontSize="40" TextColor="Black"
                       FontAttributes="Bold"/>
            
                <Label HorizontalTextAlignment="Center">
                    <Label.FormattedText>
                        <FormattedString>
                            <Span Text="Phone No : " TextColor="Gray" FontAttributes="Bold"/>
                            <Span Text="1234567890" TextColor="Green" FontAttributes="Bold"/>
                        </FormattedString>
                   </Label.FormattedText>
               </Label>
           </StackLayout>
        </Frame>
    </StackLayout>

CodePudding user response：

Of course you could do that. You could make it by using ImageFromXamarinUI Nuget. Let me give you an example:

In the xaml file, set a name for the frame you want to capture. Let's call it "myfame":

<Frame x:Name="myframe"    HasShadow="False" BorderColor="LightGray"
               CornerRadius="0" VerticalOptions="Center"
               HorizontalOptions="Center">

In the .cs file, first use the new Nuget:

using ImageFromXamarinUI;

Then use the following code:

async void TapGestureRecognizer_Tapped(System.Object sender, System.EventArgs e)
    {
        var imgStream = await myframe.CaptureImageAsync(); // take the content of myframe as a screenshot
        
        string fileName = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "mypic.png");

        using (var fileStream = new FileStream(fileName, FileMode.Create, FileAccess.Write))
        {
            imgStream.CopyTo(fileStream);
        }
    }

In iOS, you could find the png through Files App.

You should also set LSSupportsOpeningDocumentsInPlace key and Application supports iTunes sharing key to Yes.

In this way, you could capture any visual element to screenshot and save it to a png file.

===================origin post===============

As @Jason said, you could use Xamarin.Essentials: Screenshot. Try the following code:

    async void TapGestureRecognizer_Tapped(System.Object sender, System.EventArgs e)  // i save the png when tapping the frame
    {
        var screenshot = await Screenshot.CaptureAsync();
        var stream = await screenshot.OpenReadAsync();

        string fileName = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "mypic.png");

        using (var fileStream = new FileStream(fileName, FileMode.Create, FileAccess.Write))
        {
            stream.CopyTo(fileStream);
        } 
    }

In iOS, you could find the png through Files App.

You should also set LSSupportsOpeningDocumentsInPlace key and Application supports iTunes sharing key to Yes.

For more information, you could refer to Xamarin.Essentials: Screenshot and File system access in Xamarin.iOS

Hope it works for you.

CodePudding user response：

I achieved this using Dependency service.

in iOS added the below code and convert the byte[] to imagesource from contentpage.cs.

 public byte[] LayoutToImage()
    {
        var view = UIApplication.SharedApplication.KeyWindow;
       UIGraphics.BeginImageContext(view.Frame.Size);
        view.DrawViewHierarchy(view.Frame, true);
        var image = UIGraphics.GetImageFromCurrentImageContext();
        UIGraphics.EndImageContext();
       using (var imageData = image.AsPNG())
        {
            var bytes = new byte[imageData.Length];
            System.Runtime.InteropServices.Marshal.Copy(imageData.Bytes, bytes, 0, Convert.ToInt32(imageData.Length));
            return bytes;
        }