Earlier, we confirmed you tips on how to use ImageRenderer to seize a SwiftUI view and put it aside as a picture. This new class, launched in iOS 16, may also allow you to convert a view right into a PDF doc.
On this tutorial, we’ll construct on the highest of the earlier demo and add the Save to PDF operate. To observe this tutorial, please use Xcode 14 beta 3 (or up).
Revisit the Demo App
When you haven’t learn the earlier tutorial, I recommend you to test it out first. It already lined the fundamentals of ImageRenderer and defined the implementation of the demo app.
I’ve made some modifications to the demo app by including a heading and a caption for the road chart. The demo app now additionally comes with a PDF button for saving the chart view in a PDF doc. You’ll be able to confer with the code of the ChartView struct beneath:
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struct ChartView: View { let chartData = [ (city: “Hong Kong”, data: hkWeatherData), (city: “London”, data: londonWeatherData), (city: “Taipei”, data: taipeiWeatherData) ]
var physique: some View { VStack { Textual content(“Constructing Line Charts in SwiftUI”) .font(.system(measurement: 40, weight: .heavy, design: .rounded)) .multilineTextAlignment(.middle) .padding()
Chart { ForEach(chartData, id: .metropolis) { collection in ForEach(collection.information) { merchandise in LineMark( x: .worth(“Month”, merchandise.date), y: .worth(“Temp”, merchandise.temperature) ) } .foregroundStyle(by: .worth(“Metropolis”, collection.metropolis)) .image(by: .worth(“Metropolis”, collection.metropolis)) } } .chartXAxis { AxisMarks(values: .stride(by: .month)) { worth in AxisGridLine() AxisValueLabel(format: .dateTime.month(.defaultDigits))
}
} .chartPlotStyle { plotArea in plotArea .background(.blue.opacity(0.1)) } .chartYAxis { AxisMarks(place: .main) } .body(width: 350, top: 300)
.padding(.horizontal)
Textual content(“Determine 1. Line Chart”) .padding()
} } } |
Saving the Chart View as a PDF Doc Utilizing ImageRenderer
What we’re going to do is to create a PDF doc for the ChartView utilizing ImageRenderer. Whereas it solely takes a pair traces of code to transform a SwiftUI view into a picture, we want slightly extra work for PDF rendering.
For picture conversion, you may entry the uiImage property to get the rendered picture. To attract the chart right into a PDF, we’ll use the render technique of ImageRenderer. Here’s what we’re going to implement:
- Search for the doc listing and put together the rendered path for the PDF file (e.g. linechart.pdf).
- Put together an occasion of
CGContextfor drawing. - Name the
rendertechnique of the renderer to render the PDF doc.
For the implementation, we create a brand new technique named exportPDF. Under is the code of the tactic :
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@MainActor personal func exportPDF() { guard let documentDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first else { return }
let renderedUrl = documentDirectory.appending(path: “linechart.pdf”)
if let client = CGDataConsumer(url: renderedUrl as CFURL), let pdfContext = CGContext(client: client, mediaBox: nil, nil) {
let renderer = ImageRenderer(content material: chartView) renderer.render { measurement, renderer in let choices: [CFString: Any] = [ kCGPDFContextMediaBox: CGRect(origin: .zero, size: size) ]
pdfContext.beginPDFPage(choices as CFDictionary)
renderer(pdfContext) pdfContext.endPDFPage() pdfContext.closePDF() } }
print(“Saving PDF to (renderedUrl.path())”) } |
The primary two traces of the code retrieves the doc listing of the consumer and arrange the file path of the PDF file (i.e. line chart.pdf). We then create the occasion of CGContext. The mediaBox parameter is ready to nil. On this case, Core Graphics makes use of a default web page measurement of 8.5 by 11 inches (612 by 792 factors).
The renderer closure receives two parameters: the present measurement of the view, and a operate that renders the view to the CGContext. To start the PDF web page, we name the context’s beginPDFPage technique. The renderer technique attracts the chart view. And keep in mind that it is advisable to shut the PDF doc to finish the entire operation.
To name this exportPDF technique, we create a PDF button like this:
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Button { exportPDF() } label: { Label(“PDF”, systemImage: “doc.plaintext”) } .buttonStyle(.borderedProminent) |
You’ll be able to run the app in a simulator to have a check. After you faucet the PDF button, you need to see the next message within the console:
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Saving PDF to /Customers/simon/Library/Developer/CoreSimulator/Gadgets/CA9B849B–36C5–4608–9D72–B04C468DA87E/information/Containers/Knowledge/Software/04415B8A–7485–48F0–8DA2–59B97C2B529D/Paperwork/linechart.pdf |
When you open the file in Finder, you need to see a PDF doc like beneath.
To regulate the place of the drawing, you may insert this line of code earlier than calling renderer:
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pdfContext.translateBy(x: 0, y: 200) |
This can transfer the chart to the higher a part of the doc.
Make the PDF file accessible to the Recordsdata app
It’s possible you’ll surprise why the PDF file can’t be discovered within the Recordsdata app. Earlier than you may make the file accessible to the built-in Recordsdata app, you must change a few the settings in Information.plist. Change to Information.plist and add the next keys:
UIFileSharingEnabled– Software helps iTunes file sharingLSSupportsOpeningDocumentsInPlace– Helps opening paperwork in place
Set the worth of the keys to Sure. When you allow each choices, run the app on the simulator once more. Open the Recordsdata app and navigate to the On My iPhone location. It is best to see the app’s folder. Contained in the folder, you will see the PDF doc.
If you’re excited by diving deeper into SwiftUI, take a look at our Mastering SwiftUI ebook.
Founding father of AppCoda. Creator 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+.
