Add support for dynamic type (#9)

Enables dynamic type support and automatic size adjustments by default, but configurable on initialisation.

Author: lukeredpath

Demo Project/ResponsiveTextFieldDemo.xcodeproj/project.pbxproj

@@ -210,7 +210,7 @@
 				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
-				IPHONEOS_DEPLOYMENT_TARGET = 14.4;
+				IPHONEOS_DEPLOYMENT_TARGET = 14.5;
 				MTL_ENABLE_DEBUG_INFO = INCLUDE_SOURCE;
 				MTL_FAST_MATH = YES;
 				ONLY_ACTIVE_ARCH = YES;
@@ -265,7 +265,7 @@
 				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
-				IPHONEOS_DEPLOYMENT_TARGET = 14.4;
+				IPHONEOS_DEPLOYMENT_TARGET = 14.5;
 				MTL_ENABLE_DEBUG_INFO = NO;
 				MTL_FAST_MATH = YES;
 				SDKROOT = iphoneos;

Demo Project/ResponsiveTextFieldDemo/ContentView.swift

@@ -77,6 +77,7 @@ struct ContentView: View {
                         }
                     )
                 )
+                .responsiveTextFieldFont(.preferredFont(forTextStyle: .title1))
                 .responsiveKeyboardReturnType(.next)
                 .responsiveTextFieldTextColor(.blue)
                 .fixedSize(horizontal: false, vertical: true)

ResponsiveTextField.xcworkspace/contents.xcworkspacedata

@@ -48,9 +48,21 @@ public struct ResponsiveTextField {
     var returnKeyType: UIReturnKeyType
 
     /// Sets the text field font - use the `.responsiveKeyboardFont()` modifier.
+    ///
+    /// - Note: if `adjustsFontForContentSizeCategory` is `true`, the font will only be set
+    /// to this value once when the underlying text field is first created.
+    ///
     @Environment(\.textFieldFont)
     var font: UIFont
 
+    /// When `true`, configures the text field to automatically adjust its font based on the content size category.
+    ///
+    /// - Note: When set to `true`, the underlying text field will not respond to changes to the `textFieldFont`
+    /// environment variable. If you want to implement your own dynamic/state-driven font changes you should set this
+    /// to `false` and handle font size adjustment manually.
+    ///
+    var adjustsFontForContentSizeCategory: Bool
+
     /// Sets the text field color - use the `.responsiveTextFieldColor()` modifier.
     @Environment(\.textFieldTextColor)
     var textColor: UIColor
@@ -110,6 +122,7 @@ public struct ResponsiveTextField {
         placeholder: String,
         text: Binding<String>,
         isSecure: Bool = false,
+        adjustsFontForContentSizeCategory: Bool = true,
         firstResponderDemand: Binding<FirstResponderDemand?>? = nil,
         configuration: Configuration = .empty,
         onFirstResponderStateChanged: FirstResponderStateChangeHandler? = nil,
@@ -124,6 +137,7 @@ public struct ResponsiveTextField {
         self.firstResponderDemand = firstResponderDemand
         self.isSecure = isSecure
         self.configuration = configuration
+        self.adjustsFontForContentSizeCategory = adjustsFontForContentSizeCategory
         self.onFirstResponderStateChanged = onFirstResponderStateChanged
         self.handleReturn = handleReturn
         self.handleDelete = handleDelete
@@ -220,7 +234,7 @@ public struct FirstResponderStateChangeHandler {
     /// safe to perform state changes that perform a view update inside this callback. However, programatic first
     /// responder state changes (where you change the demand state connected to the `firstResponderDemand`
     /// binding passed into `ResponsiveTextField`) happen as part of a view update - i.e. the demand change
-    /// will trigger a view update and the `becomeFirstResponder()` call will happn in the `updateUIView`
+    /// will trigger a view update and the `becomeFirstResponder()` call will happen in the `updateUIView`
     /// as part of that view change event.
     ///
     /// This means that the change handler callback will be called as part of the view update and if that change handler
@@ -292,6 +306,7 @@ extension ResponsiveTextField: UIViewRepresentable {
         textField.isEnabled = isEnabled
         textField.isSecureTextEntry = isSecure
         textField.font = font
+        textField.adjustsFontForContentSizeCategory = adjustsFontForContentSizeCategory
         textField.textColor = textColor
         textField.textAlignment = textAlignment
         textField.returnKeyType = returnKeyType
@@ -318,9 +333,15 @@ extension ResponsiveTextField: UIViewRepresentable {
         uiView.isEnabled = isEnabled
         uiView.isSecureTextEntry = isSecure
         uiView.returnKeyType = returnKeyType
-        uiView.font = font
         uiView.text = text.wrappedValue
 
+        if !adjustsFontForContentSizeCategory {
+            // We should only support dynamic font changes using our own environment
+            // value if dynamic type support is disabled otherwise we will override
+            // the automatically adjusted font.
+            uiView.font = font
+        }
+
         switch (uiView.isFirstResponder, firstResponderDemand?.wrappedValue) {
         case (true, .shouldResignFirstResponder):
             uiView.resignFirstResponder()
@@ -557,6 +578,13 @@ struct ResponsiveTextField_Previews: PreviewProvider {
                 .previewLayout(.sizeThatFits)
                 .previewDisplayName("Text Styling")
 
+            TextFieldPreview(configuration: .email, text: "[email protected]")
+                .responsiveTextFieldFont(.preferredFont(forTextStyle: .body))
+                .responsiveTextFieldTextColor(.systemBlue)
+                .previewLayout(.sizeThatFits)
+                .environment(\.sizeCategory, .extraExtraExtraLarge)
+                .previewDisplayName("Dynamic Font Size")
+
             TextFieldPreview(configuration: .empty, text: "This is some text")
                 .responsiveTextFieldTextAlignment(.center)
                 .previewLayout(.sizeThatFits)