title: How to set a custom font family as the default for an entire app in SwiftUI
body: <p>In SwiftUI you get all these handy little Font convenience accessors like <code>Font.caption</code>, <code>Font.title</code>, <code>Font.body</code>, etc..</p>
  
  <p>e.g.</p>
  
  <pre><code>VStack {
   Text("Some Title").font(Font.title)
   Text("Some Caption Text").font(Font.caption)
  }
  </code></pre>
  
  <p>They all specify different font styles for the default Helvetica font family. I'd like to use these very helpful convenience accessors without ever using Helvetica in my app. <strong>Can I change the default font family?</strong> Or do I constantly have to apply custom fonts like e.g.:</p>
  
  <p><code>Text("Custom Text").font(Font.custom("SourceSansPro-Regular", size: 14.0)</code></p>