Merge pull request #351 from gazialankus/show_page_with_type_and_sele…

…ctor

Show page with type and selector

README.md

@@ -928,9 +928,10 @@ This subsection details the methods for moving within the modal's navigation
 stack, allowing users to navigate through pages effectively.
 
 #### Direct navigation
-Navigate within the modal stack using specific methods to move directly to a 
-desired page. You can go to the next or previous page, jump to a page at a 
-specific index in the page list, or navigate to a page by its unique identifier.
+Navigate within the modal stack using specific methods to move directly to a
+desired page. You can go to the next or previous page, jump to a page at a
+specific index in the page list, navigate to a page by its unique identifier,
+or even navigate based on the page type with optional filtering criteria.
 
 ```dart
 // Move to the next page
@@ -944,6 +945,14 @@ bool navigatedByIndex = WoltModalSheet.of(context).showAtIndex(2);
 
 // Navigate to a page by its unique identifier
 bool navigatedById = WoltModalSheet.of(context).showPageWithId(pageId);
+
+// Navigate to a page by its type
+bool didShowPage = WoltModalSheet.of(context).showPage<MyCustomPage>();
+
+// Navigate to a page of a certain type that meets additional criteria
+bool didShowFilteredPage = WoltModalSheet.of(context).showPage<MyCustomPage>(
+  where: (page) => page.someProperty == "desiredValue",
+);
 ```
 
 #### Pushing Pages

examples/playground/lib/home/pages/custom_sheet_pages/product_with_sku_page.dart

@@ -0,0 +1,38 @@
+import 'package:demo_ui_components/demo_ui_components.dart';
+import 'package:flutter/material.dart';
+import 'package:wolt_modal_sheet/wolt_modal_sheet.dart';
+
+class ProductWithSkuPage extends WoltModalSheetPage {
+  final int sku;
+
+  ProductWithSkuPage(this.sku)
+      : super(
+          heroImage: Stack(
+            fit: StackFit.passthrough,
+            children: [
+              const Image(
+                image: AssetImage('lib/assets/images/hero_image.jpg'),
+                fit: BoxFit.cover,
+              ),
+              Positioned(
+                right: 30,
+                bottom: 30,
+                child: Center(child: ModalSheetTitle('SKU: $sku')),
+              ),
+            ],
+          ),
+          stickyActionBar: const Padding(
+            padding: EdgeInsets.fromLTRB(16, 0, 16, 16),
+            child: WoltModalSheetCloseOrNextSab(),
+          ),
+          pageTitle: ModalSheetTitle('Product with sku $sku'),
+          leadingNavBarWidget: const WoltModalSheetBackButton(),
+          trailingNavBarWidget: const WoltModalSheetCloseButton(),
+          child: const Padding(
+            padding: EdgeInsets.only(bottom: 80, top: 16, left: 16, right: 16),
+            child: ModalSheetContentText('''
+Instead of relying on the order of pages or the id values provided to pages, we can also look pages up by type and any other arbitrary value that the page may have. This gives the user the power to address pages in ways that may not be covered by other options. 
+'''),
+          ),
+        );
+}

examples/playground/lib/home/pages/root_sheet_page.dart

@@ -1,5 +1,6 @@
 import 'package:demo_ui_components/demo_ui_components.dart';
 import 'package:flutter/material.dart';
+import 'package:playground/home/pages/custom_sheet_pages/product_with_sku_page.dart';
 import 'package:playground/home/pages/modal_page_name.dart';
 import 'package:playground/home/pages/sheet_page_with_custom_top_bar.dart';
 import 'package:playground/home/pages/sheet_page_with_min_height.dart';
@@ -27,6 +28,9 @@ class RootSheetPage {
         SheetPageWithTextField.build(),
         SheetPageWithMinHeight.build(),
         SheetPageWithInAppNavigation.build(),
+        ProductWithSkuPage(1),
+        ProductWithSkuPage(2),
+        ProductWithSkuPage(3),
         SheetPageWithCustomTopBar.build(),
         SheetPageWithNoPageTitleNoTopBar.build(),
         SheetPageWithUpdatePage.build(context, isLastPage: true),
@@ -153,8 +157,15 @@ class RootSheetPage {
                       destinationPage = SheetPageWithNonScrollingLayout.build();
                       break;
                     case ModalPageName.inAppNavigation:
-                      destinationPage = SheetPageWithInAppNavigation.build();
-                      break;
+                      WoltModalSheet.of(context).addOrReplacePages([
+                        SheetPageWithInAppNavigation.build(),
+                        ProductWithSkuPage(1),
+                        ProductWithSkuPage(2),
+                        ProductWithSkuPage(3),
+                      ]);
+                      isButtonEnabledNotifier.value =
+                          selectedItemData.isSelected;
+                      return;
                     case null:
                       WoltModalSheet.of(context).addOrReplacePages(
                         _constructAllPagesAfterRootPage(context),

examples/playground/lib/home/pages/sheet_page_with_in_app_navigation.dart

@@ -1,5 +1,6 @@
 import 'package:demo_ui_components/demo_ui_components.dart';
 import 'package:flutter/material.dart';
+import 'package:playground/home/pages/custom_sheet_pages/product_with_sku_page.dart';
 import 'package:playground/home/pages/modal_page_name.dart';
 import 'package:playground/home/pages/root_sheet_page.dart';
 import 'package:wolt_modal_sheet/wolt_modal_sheet.dart';
@@ -45,6 +46,8 @@ class SheetPageWithInAppNavigation {
               SizedBox(height: 16),
               _ButtonForShowPageWithId(),
               SizedBox(height: 16),
+              _ButtonForShowProductWithSku(),
+              SizedBox(height: 16),
             ],
           ),
         );
@@ -299,3 +302,34 @@ class _ButtonForShowPageWithId extends StatelessWidget {
     );
   }
 }
+
+class _ButtonForShowProductWithSku extends StatelessWidget {
+  const _ButtonForShowProductWithSku();
+
+  @override
+  Widget build(BuildContext context) {
+    const skus = [1, 2, 3];
+    return Row(
+      children: [
+        for (final sku in skus) ...[
+          Expanded(
+            child: WoltElevatedButton(
+              onPressed: () {
+                final didShowFilteredPage =
+                    WoltModalSheet.of(context).showPage<ProductWithSkuPage>(
+                  where: (page) => page.sku == sku,
+                );
+                String message = didShowFilteredPage
+                    ? 'Moved to product page with sku: $sku'
+                    : 'Cannot navigate: No product page with sku $sku found.';
+                _showMessage(context, message);
+              },
+              child: Text('SKU $sku'),
+            ),
+          ),
+          if (sku != skus.last) const SizedBox(width: 8),
+        ],
+      ],
+    );
+  }
+}

lib/src/wolt_modal_sheet.dart

@@ -903,6 +903,55 @@ class WoltModalSheetState extends State<WoltModalSheet> {
     }
     return false;
   }
+
+  /// Navigates to a page identified by both type and an optional selector function parameter `where`.
+  ///
+  /// This method allows specifying the page to navigate using multiple criteria:
+  ///  - The type of the page specified by `T`.
+  ///  - Arbitrary constraints on the page using the `where` parameter.
+  ///
+  /// If no page that matches these criteria is found, no navigation will occur.
+  ///
+  /// Parameters:
+  ///   - [T]: The [SliverWoltModalSheetPage] descendant type of the page to find.
+  ///   - [where]: An optional selector function to further constrain the search. For example,
+  ///     `(page) => page.id == "desired_page_id"`.
+  ///
+  /// Returns:
+  ///   - [bool]: Returns `true` if navigation to the page was successful, `false` if no page
+  ///     that matches the given criteria is found in the stack.
+  ///
+  /// Usage Examples:
+  /// ```dart
+  /// // Example 1: Navigate to the first occurrence of a page by its type
+  /// bool didShowPage = WoltModalSheet.of(context).showPage<MyCustomPage>();
+  /// if (didShowPage) {
+  ///   print("Successfully navigated to MyCustomPage.");
+  /// } else {
+  ///   print("No MyCustomPage found in the stack.");
+  /// }
+  ///
+  /// // Example 2: Navigate to a page of a certain type that meets additional criteria
+  /// bool didShowFilteredPage = WoltModalSheet.of(context).showPage<MyCustomPage>(
+  ///   where: (page) => page.id == "some_unique_page_id",
+  /// );
+  /// if (didShowFilteredPage) {
+  ///   print("Successfully navigated to the MyCustomPage with ID 'some_unique_page_id'.");
+  /// } else {
+  ///   print("No MyCustomPage with the specified ID found in the stack.");
+  /// }
+  /// ```
+  bool showPage<T extends SliverWoltModalSheetPage>({
+    bool Function(T page)? where,
+  }) {
+    final index = _pages
+        .indexWhere(where == null ? (p) => p is T : (p) => p is T && where(p));
+    if (index != -1) {
+      _currentPageIndex = index;
+      return true;
+    }
+    return false;
+  }
 }
 
 class _WoltModalMultiChildLayoutDelegate extends MultiChildLayoutDelegate {