Docs updated

native/src/widget/text_input.rs

@@ -81,8 +81,7 @@ where
     ///
     /// It expects:
     /// - a placeholder,
-    /// - the current value, and
-    /// - a function that produces a message when the [`TextInput`] changes.
+    /// - the current value
     pub fn new(placeholder: &str, value: &str) -> Self {
         TextInput {
             id: None,
@@ -164,6 +163,7 @@ where
     }
 
     /// Sets the callback which is called when the text gets changed
+    /// If not specified, the widget will be disabled
     pub fn on_change<F>(mut self, callback: F) -> Self
     where
         F: 'a + Fn(String) -> Message,