Disabling suggestions on Android if readonly mode is set.

android/src/toga_android/widgets/textinput.py

@@ -77,9 +77,19 @@ def set_readonly(self, readonly):
         if readonly:
             # Implicitly calls setFocusableInTouchMode(False)
             self.native.setFocusable(False)
+            # Add TYPE_TEXT_FLAG_NO_SUGGESTIONS to the input type to disable suggestions
+            input_type = (
+                self.native.getInputType() | InputType.TYPE_TEXT_FLAG_NO_SUGGESTIONS
+            )
+            self.native.setInputType(input_type)
         else:
             # Implicitly calls setFocusable(True)
             self.native.setFocusableInTouchMode(True)
+            # Remove TYPE_TEXT_FLAG_NO_SUGGESTIONS to enable suggestions
+            input_type = (
+                self.native.getInputType() & ~InputType.TYPE_TEXT_FLAG_NO_SUGGESTIONS
+            )
+            self.native.setInputType(input_type)
 
     def get_placeholder(self):
         return str(self.native.getHint())

android/tests_backend/widgets/textinput.py

@@ -38,6 +38,22 @@ def readonly(self):
         focusable_in_touch_mode = self.native.isFocusableInTouchMode()
         if focusable != focusable_in_touch_mode:
             raise ValueError(f"invalid state: {focusable=}, {focusable_in_touch_mode=}")
+
+        # Check if TYPE_TEXT_FLAG_NO_SUGGESTIONS is set in the input type
+        input_type = self.native.getInputType()
+        if input_type & InputType.TYPE_TEXT_FLAG_NO_SUGGESTIONS:
+            # TYPE_TEXT_FLAG_NO_SUGGESTIONS is set
+            if focusable:
+                raise ValueError(
+                    "TYPE_TEXT_FLAG_NO_SUGGESTIONS is not set on the input."
+                )
+        else:
+            # TYPE_TEXT_FLAG_NO_SUGGESTIONS is not set
+            if not focusable:
+                raise ValueError(
+                    "TYPE_TEXT_FLAG_NO_SUGGESTIONS has been set when the input is readonly."
+                )
+
         return not focusable
 
     async def type_character(self, char):

changes/2136.bugfix.rst

@@ -0,0 +1 @@
+Multiline text inputs no longer show spelling suggestions when in readonly mode.