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Utilizing ImageRenderer to Convert SwiftUI Views into Pictures

ImageRenderer is one other new API for SwiftUI that comes with iOS 16. It permits you to simply convert any SwiftUI views into a picture. The implementation may be very easy. You instantiate an occasion of ImageRenderer with a view for the conversion:

You may then entry the cgImage or uiImage property to retrieve the generated picture.

As at all times, I like to display the utilization of an API with an instance. Earlier, we’ve constructed a line chart utilizing the brand new Charts framework. Let’s see let customers save the chart as a picture within the photograph album and share it utilizing ShareLink.

Revisit the Chart View


First, let’s revisit the code of the ChartView instance. We used the brand new API of the Charts framework to create a line chart and show the climate knowledge. Right here is the code snippet:

To make use of ImageRenderer, we first refactor this piece of code right into a separate view like this:

Subsequent, we declare a variable to carry the view:

Changing the View into an Picture utilizing ImageRenderer

Now we’re able to convert the chart view into a picture. We are going to add a button named Save to Pictures for saving the chart view picture within the photograph album.

Let’s implement the button like this:

Within the closure of the button, we create an occasion of ImageRenderer with chartView and get the rendered picture by utilizing the uiImage property. Then we name UIImageWriteToSavedPhotosAlbum to avoid wasting the picture to the photograph album.

Be aware: You’ll want to add a key named Privateness – Photograph Library Utilization Description within the information.plist earlier than the app can correctly save a picture to the built-in photograph album.

Including a Share Button


Earlier, you discovered use ShareLink to current a share sheet for content material sharing. With ImageRenderer, you may simply construct a perform for customers to share the chart view.

For comfort goal, let’s refactor the code for picture rendering right into a separate technique:

The generateSnapshot technique converts the chartView into a picture.

Be aware: In case you are new to @MainActor, you may try this text.

With this helper technique, we are able to create a ShareLink like this within the VStack view:

Now while you faucet the Share button, the app captures the road chart and allows you to share it as a picture.


Adjusting the Picture Scale

It’s possible you’ll discover the decision of the rendered picture is a bit low. The ImageRenderer class has a property named scale so that you can modify the size of the rendered picture. By default, its worth is ready to 1.0. To generate a picture with the next decision, you may set it to 2.0 or 3.0. Alternatively, you may set the worth to the size of the display:


The ImageRenderer class has made it very straightforward to transform any SwiftUI views into a picture. In case your app helps iOS 16 or up, you need to use this new API to create some handy options in your customers. Aside from rendering pictures, ImageRenderer additionally permits you to render a PDF doc. You may seek advice from the official documentation for additional particulars.

For charts, Apple additionally comes with a extra particular renderer referred to as ChartRenderer for exporting a chart as a picture. Later, we are going to additional look into this class.

Founding father of AppCoda. Writer of a number of iOS programming books together with Starting iOS Programming with Swift and Mastering SwiftUI. iOS App Developer and Blogger. Observe me at Fb, Twitter and Google+.



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