docs: update readme option docs (#59)

* docs: update readme option docs

* remove redundant nullability docs

README.md

@@ -113,41 +113,35 @@ InfiniteList<String>(
   // While set to `true`, the [onFetchData] callback will not be triggered
   // and the [loadingBuilder] will be rendered.
   //
-  // Is set to `false` by default and cannot be `null`.
+  // Is set to `false` by default.
   isLoading: false,
 
   // Indicates if an error has occurred.
   //
   // While set to `true`, the [onFetchData] callback will not be triggered
   // and the [errorBuilder] will be rendered.
   //
-  // Is set to `false` by default and cannot be `null`.
+  // Is set to `false` by default.
   hasError: false,
 
   // Indicates if the list should be reversed.
   //
   // If set to `true`, the list of items, [loadingBuilder] and [errorBuilder]
   // will be rendered from bottom to top.
+  //
+  // Is set to `false` by default.
   reverse: false,
 
   // The duration with which calls to [onFetchData] will be debounced.
   //
-  // Is set to a duration of 100 milliseconds by default and cannot be `null`.
+  // Is set to a duration of 100 milliseconds by default.
   debounceDuration: const Duration(milliseconds: 100),
 
-  // The offset, in pixels, that the [scrollController] must be scrolled over
+  // The offset, in pixels, that the internal [ScrollView] must be scrolled over
   // to trigger [onFetchData].
-  //
-  // This is useful for fetching data _before_ the user has scrolled all the
-  // way to the end of the list, so the fetching mechanism is more well hidden.
-  //
-  // For example, if this is set to `400.0` (the default), [onFetchData] will
-  // be called when the list is scrolled `400.0` pixels away from the bottom
-  // (or the top if [reverse] is `true`).
-  //
-  // This value must be `0.0` or greater, is set to `400.0` by default and
-  // cannot be `null`.
-  scrollExtentThreshold: 400.0,
+  // 
+  // Defaults to the same as [RenderAbstractViewport.defaultCacheExtent], which is 250.
+  cacheExtent: 250.0,
 
   // The amount of space by which to inset the list of items.
   //
@@ -188,6 +182,17 @@ InfiniteList<String>(
   //
   // Is optional and can be `null`.
   separatorBuilder: (context, index) => const Divider(),
+
+  // An optional [Axis] to be used by the internal [ScrollView] that defines
+  // the axis of scroll. 
+  //
+  // Is set to `Axis.vertical` by default.
+  scrollDirection: Axis.vertical,
+
+  // An optional [ScrollPhysics] to be used by the internal [ScrollView].
+  //
+  // Default to tha same as [ScrollView].
+  physics: const AlwaysScrollableScrollPhysics(),
 );
 ```
 

lib/src/infinite_list.dart

@@ -14,7 +14,7 @@ import 'package:very_good_infinite_list/src/sliver_infinite_list.dart';
 /// [onFetchData] will be called automatically.
 ///
 /// The [itemCount], [hasReachedMax], [onFetchData] and [itemBuilder] must be
-/// provided and cannot be `null`.
+/// provided.
 /// {@endtemplate}
 ///
 /// See also:
@@ -64,7 +64,7 @@ class InfiniteList extends StatelessWidget {
   /// {@template debounce_duration}
   /// The duration with which calls to [onFetchData] will be debounced.
   ///
-  /// Is set to [defaultDebounceDuration] by default and cannot be `null`.
+  /// Is set to [defaultDebounceDuration] by default.
   /// {@endtemplate}
   final Duration debounceDuration;
 
@@ -79,7 +79,7 @@ class InfiniteList extends StatelessWidget {
   /// {@template item_count}
   /// The amount of items that need to be rendered by the [itemBuilder].
   ///
-  /// Is required and cannot be `null`.
+  /// Is required.
   /// {@endtemplate}
   final int itemCount;
 
@@ -89,7 +89,7 @@ class InfiniteList extends StatelessWidget {
   /// While set to `true`, the [onFetchData] callback will not be triggered
   /// and the [loadingBuilder] will be rendered.
   ///
-  /// Is set to `false` by default and cannot be `null`.
+  /// Is set to `false` by default.
   /// {@endtemplate}
   final bool isLoading;
 
@@ -99,7 +99,7 @@ class InfiniteList extends StatelessWidget {
   /// While set to `true`, the [onFetchData] callback will not be triggered
   /// and the [errorBuilder] will be rendered.
   ///
-  /// Is set to `false` by default and cannot be `null`.
+  /// Is set to `false` by default.
   /// {@endtemplate}
   final bool hasError;
 
@@ -109,7 +109,7 @@ class InfiniteList extends StatelessWidget {
   ///
   /// While set to `true`, the [onFetchData] callback will not be triggered.
   ///
-  /// Is set to `false` by default and cannot be `null`.
+  /// Is set to `false` by default.
   /// {@endtemplate}
   final bool hasReachedMax;
 
@@ -124,17 +124,15 @@ class InfiniteList extends StatelessWidget {
   /// Additionally, every call to this will be debounced by the provided
   /// [debounceDuration].
   ///
-  /// Is required and cannot be `null`.
+  /// Is required.
   /// {@endtemplate}
   final VoidCallback onFetchData;
 
   /// See [RenderViewportBase.cacheExtent]
   final double? cacheExtent;
 
   /// {@template padding}
-  /// The amount of space by which to inset the list of items.
-  ///
-  /// Is optional and can be `null`.
+  /// The optional amount of space by which to inset the list of items.
   /// {@endtemplate}
   final EdgeInsets? padding;
 
@@ -165,15 +163,13 @@ class InfiniteList extends StatelessWidget {
   ///
   /// If the [itemBuilder] returns a [ListTile], this is commonly used to render
   /// a [Divider] between every tile.
-  ///
-  /// Is optional and can be `null`.
   /// {@endtemplate}
   final IndexedWidgetBuilder? separatorBuilder;
 
   /// {@template item_builder}
   /// The builder used to build a widget for every index of the `itemCount`.
   ///
-  /// Is required and cannot be `null`.
+  /// Is required.
   /// {@endtemplate}
   final ItemBuilder itemBuilder;