feat: unify navigation handling with system-wide continuous navigation (#600)

This PR unifies navigation handling & adds system-wide support for
continuous navigation.

## Summary
Holding down a navigation button now continuously advances through items
until the button is released. This removes the need for repeated
press-and-release actions and makes navigation faster and smoother,
especially in long menus or documents.

When page-based navigation is available, it will navigate through pages.
If not, it will progress through menu items or similar list-based UI
elements.

Additionally, this PR fixes inconsistencies in wrap-around behavior and
navigation index calculations.

Places where the navigation system was updated:
- Home Page
- Settings Pages
- My Library Page
- WiFi Selection Page
- OPDS Browser Page
- Keyboard
- File Transfer Page
- XTC Chapter Selector Page
- EPUB Chapter Selector Page

I’ve tested this on the device as much as possible and tried to match
the existing behavior. Please let me know if I missed anything. Thanks 🙏


![crosspoint](https://github.com/user-attachments/assets/6a3c7482-f45e-4a77-b156-721bb3b679e6)

---

Following the request from @osteotek and @daveallie for system-wide
support, the old PR (#379) has been closed in favor of this
consolidated, system-wide implementation.

---

### AI Usage

Did you use AI tools to help write this code? _**PARTIALLY**_

---------

Co-authored-by: Dave Allie <dave@daveallie.com>

src/activities/browser/OpdsBookBrowserActivity.cpp

@@ -17,7 +17,6 @@
 
 namespace {
 constexpr int PAGE_ITEMS = 23;
-constexpr int SKIP_PAGE_MS = 700;
 }  // namespace
 
 void OpdsBookBrowserActivity::taskTrampoline(void* param) {
@@ -118,12 +117,6 @@ void OpdsBookBrowserActivity::loop() {
 
   // Handle browsing state
   if (state == BrowserState::BROWSING) {
-    const bool prevReleased = mappedInput.wasReleased(MappedInputManager::Button::Up) ||
-                              mappedInput.wasReleased(MappedInputManager::Button::Left);
-    const bool nextReleased = mappedInput.wasReleased(MappedInputManager::Button::Down) ||
-                              mappedInput.wasReleased(MappedInputManager::Button::Right);
-    const bool skipPage = mappedInput.getHeldTime() > SKIP_PAGE_MS;
-
     if (mappedInput.wasReleased(MappedInputManager::Button::Confirm)) {
       if (!entries.empty()) {
         const auto& entry = entries[selectorIndex];
@@ -135,20 +128,29 @@ void OpdsBookBrowserActivity::loop() {
       }
     } else if (mappedInput.wasReleased(MappedInputManager::Button::Back)) {
       navigateBack();
-    } else if (prevReleased && !entries.empty()) {
-      if (skipPage) {
-        selectorIndex = ((selectorIndex / PAGE_ITEMS - 1) * PAGE_ITEMS + entries.size()) % entries.size();
-      } else {
-        selectorIndex = (selectorIndex + entries.size() - 1) % entries.size();
-      }
-      updateRequired = true;
-    } else if (nextReleased && !entries.empty()) {
-      if (skipPage) {
-        selectorIndex = ((selectorIndex / PAGE_ITEMS + 1) * PAGE_ITEMS) % entries.size();
-      } else {
-        selectorIndex = (selectorIndex + 1) % entries.size();
-      }
-      updateRequired = true;
+    }
+
+    // Handle navigation
+    if (!entries.empty()) {
+      buttonNavigator.onNextRelease([this] {
+        selectorIndex = ButtonNavigator::nextIndex(selectorIndex, entries.size());
+        updateRequired = true;
+      });
+
+      buttonNavigator.onPreviousRelease([this] {
+        selectorIndex = ButtonNavigator::previousIndex(selectorIndex, entries.size());
+        updateRequired = true;
+      });
+
+      buttonNavigator.onNextContinuous([this] {
+        selectorIndex = ButtonNavigator::nextPageIndex(selectorIndex, entries.size(), PAGE_ITEMS);
+        updateRequired = true;
+      });
+
+      buttonNavigator.onPreviousContinuous([this] {
+        selectorIndex = ButtonNavigator::previousPageIndex(selectorIndex, entries.size(), PAGE_ITEMS);
+        updateRequired = true;
+      });
     }
   }
 }

src/activities/browser/OpdsBookBrowserActivity.h

@@ -9,6 +9,7 @@
 #include <vector>
 
 #include "../ActivityWithSubactivity.h"
+#include "util/ButtonNavigator.h"
 
 /**
  * Activity for browsing and downloading books from an OPDS server.
@@ -37,6 +38,7 @@ class OpdsBookBrowserActivity final : public ActivityWithSubactivity {
  private:
   TaskHandle_t displayTaskHandle = nullptr;
   SemaphoreHandle_t renderingMutex = nullptr;
+  ButtonNavigator buttonNavigator;
   bool updateRequired = false;
 
   BrowserState state = BrowserState::LOADING;

src/activities/home/HomeActivity.cpp

@@ -196,13 +196,18 @@ void HomeActivity::freeCoverBuffer() {
 }
 
 void HomeActivity::loop() {
-  const bool prevPressed = mappedInput.wasPressed(MappedInputManager::Button::Up) ||
-                           mappedInput.wasPressed(MappedInputManager::Button::Left);
-  const bool nextPressed = mappedInput.wasPressed(MappedInputManager::Button::Down) ||
-                           mappedInput.wasPressed(MappedInputManager::Button::Right);
-
   const int menuCount = getMenuItemCount();
 
+  buttonNavigator.onNext([this, menuCount] {
+    selectorIndex = ButtonNavigator::nextIndex(selectorIndex, menuCount);
+    updateRequired = true;
+  });
+
+  buttonNavigator.onPrevious([this, menuCount] {
+    selectorIndex = ButtonNavigator::previousIndex(selectorIndex, menuCount);
+    updateRequired = true;
+  });
+
   if (mappedInput.wasReleased(MappedInputManager::Button::Confirm)) {
     // Calculate dynamic indices based on which options are available
     int idx = 0;
@@ -226,12 +231,6 @@ void HomeActivity::loop() {
     } else if (menuSelectedIndex == settingsIdx) {
       onSettingsOpen();
     }
-  } else if (prevPressed) {
-    selectorIndex = (selectorIndex + menuCount - 1) % menuCount;
-    updateRequired = true;
-  } else if (nextPressed) {
-    selectorIndex = (selectorIndex + 1) % menuCount;
-    updateRequired = true;
   }
 }
 

src/activities/home/HomeActivity.h

@@ -8,6 +8,7 @@
 
 #include "../Activity.h"
 #include "./MyLibraryActivity.h"
+#include "util/ButtonNavigator.h"
 
 struct RecentBook;
 struct Rect;
@@ -15,6 +16,7 @@ struct Rect;
 class HomeActivity final : public Activity {
   TaskHandle_t displayTaskHandle = nullptr;
   SemaphoreHandle_t renderingMutex = nullptr;
+  ButtonNavigator buttonNavigator;
   int selectorIndex = 0;
   bool updateRequired = false;
   bool recentsLoading = false;

src/activities/home/MyLibraryActivity.cpp

@@ -11,7 +11,6 @@
 #include "util/StringUtils.h"
 
 namespace {
-constexpr int SKIP_PAGE_MS = 700;
 constexpr unsigned long GO_HOME_MS = 1000;
 }  // namespace
 
@@ -109,13 +108,6 @@ void MyLibraryActivity::loop() {
     return;
   }
 
-  const bool upReleased = mappedInput.wasReleased(MappedInputManager::Button::Left) ||
-                          mappedInput.wasReleased(MappedInputManager::Button::Up);
-  ;
-  const bool downReleased = mappedInput.wasReleased(MappedInputManager::Button::Right) ||
-                            mappedInput.wasReleased(MappedInputManager::Button::Down);
-
-  const bool skipPage = mappedInput.getHeldTime() > SKIP_PAGE_MS;
   const int pageItems = UITheme::getInstance().getNumberOfItemsPerPage(renderer, true, false, true, false);
 
   if (mappedInput.wasReleased(MappedInputManager::Button::Confirm)) {
@@ -157,21 +149,26 @@ void MyLibraryActivity::loop() {
   }
 
   int listSize = static_cast<int>(files.size());
-  if (upReleased) {
-    if (skipPage) {
-      selectorIndex = std::max(static_cast<int>((selectorIndex / pageItems - 1) * pageItems), 0);
-    } else {
-      selectorIndex = (selectorIndex + listSize - 1) % listSize;
-    }
+
+  buttonNavigator.onNextRelease([this, listSize] {
+    selectorIndex = ButtonNavigator::nextIndex(static_cast<int>(selectorIndex), listSize);
     updateRequired = true;
-  } else if (downReleased) {
-    if (skipPage) {
-      selectorIndex = std::min(static_cast<int>((selectorIndex / pageItems + 1) * pageItems), listSize - 1);
-    } else {
-      selectorIndex = (selectorIndex + 1) % listSize;
-    }
+  });
+
+  buttonNavigator.onPreviousRelease([this, listSize] {
+    selectorIndex = ButtonNavigator::previousIndex(static_cast<int>(selectorIndex), listSize);
     updateRequired = true;
-  }
+  });
+
+  buttonNavigator.onNextContinuous([this, listSize, pageItems] {
+    selectorIndex = ButtonNavigator::nextPageIndex(static_cast<int>(selectorIndex), listSize, pageItems);
+    updateRequired = true;
+  });
+
+  buttonNavigator.onPreviousContinuous([this, listSize, pageItems] {
+    selectorIndex = ButtonNavigator::previousPageIndex(static_cast<int>(selectorIndex), listSize, pageItems);
+    updateRequired = true;
+  });
 }
 
 void MyLibraryActivity::displayTaskLoop() {
@@ -217,4 +214,4 @@ size_t MyLibraryActivity::findEntry(const std::string& name) const {
   for (size_t i = 0; i < files.size(); i++)
     if (files[i] == name) return i;
   return 0;
-}
+}

src/activities/home/MyLibraryActivity.h

@@ -8,11 +8,14 @@
 #include <vector>
 
 #include "../Activity.h"
+#include "RecentBooksStore.h"
+#include "util/ButtonNavigator.h"
 
 class MyLibraryActivity final : public Activity {
  private:
   TaskHandle_t displayTaskHandle = nullptr;
   SemaphoreHandle_t renderingMutex = nullptr;
+  ButtonNavigator buttonNavigator;
 
   size_t selectorIndex = 0;
   bool updateRequired = false;

src/activities/home/RecentBooksActivity.cpp

@@ -12,7 +12,6 @@
 #include "util/StringUtils.h"
 
 namespace {
-constexpr int SKIP_PAGE_MS = 700;
 constexpr unsigned long GO_HOME_MS = 1000;
 }  // namespace
 
@@ -70,13 +69,6 @@ void RecentBooksActivity::onExit() {
 }
 
 void RecentBooksActivity::loop() {
-  const bool upReleased = mappedInput.wasReleased(MappedInputManager::Button::Left) ||
-                          mappedInput.wasReleased(MappedInputManager::Button::Up);
-  ;
-  const bool downReleased = mappedInput.wasReleased(MappedInputManager::Button::Right) ||
-                            mappedInput.wasReleased(MappedInputManager::Button::Down);
-
-  const bool skipPage = mappedInput.getHeldTime() > SKIP_PAGE_MS;
   const int pageItems = UITheme::getInstance().getNumberOfItemsPerPage(renderer, true, false, true, true);
 
   if (mappedInput.wasReleased(MappedInputManager::Button::Confirm)) {
@@ -92,21 +84,26 @@ void RecentBooksActivity::loop() {
   }
 
   int listSize = static_cast<int>(recentBooks.size());
-  if (upReleased) {
-    if (skipPage) {
-      selectorIndex = std::max(static_cast<int>((selectorIndex / pageItems - 1) * pageItems), 0);
-    } else {
-      selectorIndex = (selectorIndex + listSize - 1) % listSize;
-    }
+
+  buttonNavigator.onNextRelease([this, listSize] {
+    selectorIndex = ButtonNavigator::nextIndex(static_cast<int>(selectorIndex), listSize);
     updateRequired = true;
-  } else if (downReleased) {
-    if (skipPage) {
-      selectorIndex = std::min(static_cast<int>((selectorIndex / pageItems + 1) * pageItems), listSize - 1);
-    } else {
-      selectorIndex = (selectorIndex + 1) % listSize;
-    }
+  });
+
+  buttonNavigator.onPreviousRelease([this, listSize] {
+    selectorIndex = ButtonNavigator::previousIndex(static_cast<int>(selectorIndex), listSize);
     updateRequired = true;
-  }
+  });
+
+  buttonNavigator.onNextContinuous([this, listSize, pageItems] {
+    selectorIndex = ButtonNavigator::nextPageIndex(static_cast<int>(selectorIndex), listSize, pageItems);
+    updateRequired = true;
+  });
+
+  buttonNavigator.onPreviousContinuous([this, listSize, pageItems] {
+    selectorIndex = ButtonNavigator::previousPageIndex(static_cast<int>(selectorIndex), listSize, pageItems);
+    updateRequired = true;
+  });
 }
 
 void RecentBooksActivity::displayTaskLoop() {

src/activities/home/RecentBooksActivity.h

@@ -9,11 +9,13 @@
 
 #include "../Activity.h"
 #include "RecentBooksStore.h"
+#include "util/ButtonNavigator.h"
 
 class RecentBooksActivity final : public Activity {
  private:
   TaskHandle_t displayTaskHandle = nullptr;
   SemaphoreHandle_t renderingMutex = nullptr;
+  ButtonNavigator buttonNavigator;
 
   size_t selectorIndex = 0;
   bool updateRequired = false;

src/activities/network/NetworkModeSelectionActivity.cpp

@@ -73,18 +73,15 @@ void NetworkModeSelectionActivity::loop() {
   }
 
   // Handle navigation
-  const bool prevPressed = mappedInput.wasPressed(MappedInputManager::Button::Up) ||
-                           mappedInput.wasPressed(MappedInputManager::Button::Left);
-  const bool nextPressed = mappedInput.wasPressed(MappedInputManager::Button::Down) ||
-                           mappedInput.wasPressed(MappedInputManager::Button::Right);
+  buttonNavigator.onNext([this] {
+    selectedIndex = ButtonNavigator::nextIndex(selectedIndex, MENU_ITEM_COUNT);
+    updateRequired = true;
+  });
 
-  if (prevPressed) {
-    selectedIndex = (selectedIndex + MENU_ITEM_COUNT - 1) % MENU_ITEM_COUNT;
+  buttonNavigator.onPrevious([this] {
+    selectedIndex = ButtonNavigator::previousIndex(selectedIndex, MENU_ITEM_COUNT);
     updateRequired = true;
-  } else if (nextPressed) {
-    selectedIndex = (selectedIndex + 1) % MENU_ITEM_COUNT;
-    updateRequired = true;
-  }
+  });
 }
 
 void NetworkModeSelectionActivity::displayTaskLoop() {

src/activities/network/NetworkModeSelectionActivity.h

@@ -6,6 +6,7 @@
 #include <functional>
 
 #include "../Activity.h"
+#include "util/ButtonNavigator.h"
 
 // Enum for network mode selection
 enum class NetworkMode { JOIN_NETWORK, CONNECT_CALIBRE, CREATE_HOTSPOT };
@@ -22,6 +23,8 @@ enum class NetworkMode { JOIN_NETWORK, CONNECT_CALIBRE, CREATE_HOTSPOT };
 class NetworkModeSelectionActivity final : public Activity {
   TaskHandle_t displayTaskHandle = nullptr;
   SemaphoreHandle_t renderingMutex = nullptr;
+  ButtonNavigator buttonNavigator;
+
   int selectedIndex = 0;
   bool updateRequired = false;
   const std::function<void(NetworkMode)> onModeSelected;

src/activities/network/WifiSelectionActivity.cpp

@@ -420,20 +420,16 @@ void WifiSelectionActivity::loop() {
       return;
     }
 
-    // Handle UP/DOWN navigation
-    if (mappedInput.wasPressed(MappedInputManager::Button::Up) ||
-        mappedInput.wasPressed(MappedInputManager::Button::Left)) {
-      if (selectedNetworkIndex > 0) {
-        selectedNetworkIndex--;
-        updateRequired = true;
-      }
-    } else if (mappedInput.wasPressed(MappedInputManager::Button::Down) ||
-               mappedInput.wasPressed(MappedInputManager::Button::Right)) {
-      if (!networks.empty() && selectedNetworkIndex < static_cast<int>(networks.size()) - 1) {
-        selectedNetworkIndex++;
-        updateRequired = true;
-      }
-    }
+    // Handle navigation
+    buttonNavigator.onNext([this] {
+      selectedNetworkIndex = ButtonNavigator::nextIndex(selectedNetworkIndex, networks.size());
+      updateRequired = true;
+    });
+
+    buttonNavigator.onPrevious([this] {
+      selectedNetworkIndex = ButtonNavigator::previousIndex(selectedNetworkIndex, networks.size());
+      updateRequired = true;
+    });
   }
 }
 

src/activities/network/WifiSelectionActivity.h

@@ -10,6 +10,7 @@
 #include <vector>
 
 #include "activities/ActivityWithSubactivity.h"
+#include "util/ButtonNavigator.h"
 
 // Structure to hold WiFi network information
 struct WifiNetworkInfo {
@@ -45,6 +46,7 @@ enum class WifiSelectionState {
 class WifiSelectionActivity final : public ActivityWithSubactivity {
   TaskHandle_t displayTaskHandle = nullptr;
   SemaphoreHandle_t renderingMutex = nullptr;
+  ButtonNavigator buttonNavigator;
   bool updateRequired = false;
   WifiSelectionState state = WifiSelectionState::SCANNING;
   int selectedNetworkIndex = 0;

src/activities/reader/EpubReaderChapterSelectionActivity.cpp

@@ -6,11 +6,6 @@
 #include "components/UITheme.h"
 #include "fontIds.h"
 
-namespace {
-// Time threshold for treating a long press as a page-up/page-down
-constexpr int SKIP_PAGE_MS = 700;
-}  // namespace
-
 int EpubReaderChapterSelectionActivity::getTotalItems() const { return epub->getTocItemsCount(); }
 
 int EpubReaderChapterSelectionActivity::getPageItems() const {
@@ -77,12 +72,6 @@ void EpubReaderChapterSelectionActivity::loop() {
     return;
   }
 
-  const bool prevReleased = mappedInput.wasReleased(MappedInputManager::Button::Up) ||
-                            mappedInput.wasReleased(MappedInputManager::Button::Left);
-  const bool nextReleased = mappedInput.wasReleased(MappedInputManager::Button::Down) ||
-                            mappedInput.wasReleased(MappedInputManager::Button::Right);
-
-  const bool skipPage = mappedInput.getHeldTime() > SKIP_PAGE_MS;
   const int pageItems = getPageItems();
   const int totalItems = getTotalItems();
 
@@ -95,21 +84,27 @@ void EpubReaderChapterSelectionActivity::loop() {
     }
   } else if (mappedInput.wasReleased(MappedInputManager::Button::Back)) {
     onGoBack();
-  } else if (prevReleased) {
-    if (skipPage) {
-      selectorIndex = ((selectorIndex / pageItems - 1) * pageItems + totalItems) % totalItems;
-    } else {
-      selectorIndex = (selectorIndex + totalItems - 1) % totalItems;
-    }
-    updateRequired = true;
-  } else if (nextReleased) {
-    if (skipPage) {
-      selectorIndex = ((selectorIndex / pageItems + 1) * pageItems) % totalItems;
-    } else {
-      selectorIndex = (selectorIndex + 1) % totalItems;
-    }
-    updateRequired = true;
   }
+
+  buttonNavigator.onNextRelease([this, totalItems] {
+    selectorIndex = ButtonNavigator::nextIndex(selectorIndex, totalItems);
+    updateRequired = true;
+  });
+
+  buttonNavigator.onPreviousRelease([this, totalItems] {
+    selectorIndex = ButtonNavigator::previousIndex(selectorIndex, totalItems);
+    updateRequired = true;
+  });
+
+  buttonNavigator.onNextContinuous([this, totalItems, pageItems] {
+    selectorIndex = ButtonNavigator::nextPageIndex(selectorIndex, totalItems, pageItems);
+    updateRequired = true;
+  });
+
+  buttonNavigator.onPreviousContinuous([this, totalItems, pageItems] {
+    selectorIndex = ButtonNavigator::previousPageIndex(selectorIndex, totalItems, pageItems);
+    updateRequired = true;
+  });
 }
 
 void EpubReaderChapterSelectionActivity::displayTaskLoop() {

src/activities/reader/EpubReaderChapterSelectionActivity.h

@@ -7,12 +7,14 @@
 #include <memory>
 
 #include "../ActivityWithSubactivity.h"
+#include "util/ButtonNavigator.h"
 
 class EpubReaderChapterSelectionActivity final : public ActivityWithSubactivity {
   std::shared_ptr<Epub> epub;
   std::string epubPath;
   TaskHandle_t displayTaskHandle = nullptr;
   SemaphoreHandle_t renderingMutex = nullptr;
+  ButtonNavigator buttonNavigator;
   int currentSpineIndex = 0;
   int currentPage = 0;
   int totalPagesInSpine = 0;

src/activities/reader/EpubReaderMenuActivity.cpp

@@ -48,16 +48,19 @@ void EpubReaderMenuActivity::loop() {
     return;
   }
 
+  // Handle navigation
+  buttonNavigator.onNext([this] {
+    selectedIndex = ButtonNavigator::nextIndex(selectedIndex, static_cast<int>(menuItems.size()));
+    updateRequired = true;
+  });
+
+  buttonNavigator.onPrevious([this] {
+    selectedIndex = ButtonNavigator::previousIndex(selectedIndex, static_cast<int>(menuItems.size()));
+    updateRequired = true;
+  });
+
   // Use local variables for items we need to check after potential deletion
-  if (mappedInput.wasReleased(MappedInputManager::Button::Up) ||
-      mappedInput.wasReleased(MappedInputManager::Button::Left)) {
-    selectedIndex = (selectedIndex + menuItems.size() - 1) % menuItems.size();
-    updateRequired = true;
-  } else if (mappedInput.wasReleased(MappedInputManager::Button::Down) ||
-             mappedInput.wasReleased(MappedInputManager::Button::Right)) {
-    selectedIndex = (selectedIndex + 1) % menuItems.size();
-    updateRequired = true;
-  } else if (mappedInput.wasReleased(MappedInputManager::Button::Confirm)) {
+  if (mappedInput.wasReleased(MappedInputManager::Button::Confirm)) {
     const auto selectedAction = menuItems[selectedIndex].action;
     if (selectedAction == MenuAction::ROTATE_SCREEN) {
       // Cycle orientation preview locally; actual rotation happens on menu exit.

src/activities/reader/EpubReaderMenuActivity.h

@@ -9,6 +9,7 @@
 #include <vector>
 
 #include "../ActivityWithSubactivity.h"
+#include "util/ButtonNavigator.h"
 
 class EpubReaderMenuActivity final : public ActivityWithSubactivity {
  public:
@@ -48,6 +49,7 @@ class EpubReaderMenuActivity final : public ActivityWithSubactivity {
   bool updateRequired = false;
   TaskHandle_t displayTaskHandle = nullptr;
   SemaphoreHandle_t renderingMutex = nullptr;
+  ButtonNavigator buttonNavigator;
   std::string title = "Reader Menu";
   uint8_t pendingOrientation = 0;
   const std::vector<const char*> orientationLabels = {"Portrait", "Landscape CW", "Inverted", "Landscape CCW"};

src/activities/reader/EpubReaderPercentSelectionActivity.cpp

@@ -79,25 +79,11 @@ void EpubReaderPercentSelectionActivity::loop() {
     return;
   }
 
-  if (mappedInput.wasReleased(MappedInputManager::Button::Left)) {
-    adjustPercent(-kSmallStep);
-    return;
-  }
+  buttonNavigator.onPressAndContinuous({MappedInputManager::Button::Left}, [this] { adjustPercent(-kSmallStep); });
+  buttonNavigator.onPressAndContinuous({MappedInputManager::Button::Right}, [this] { adjustPercent(kSmallStep); });
 
-  if (mappedInput.wasReleased(MappedInputManager::Button::Right)) {
-    adjustPercent(kSmallStep);
-    return;
-  }
-
-  if (mappedInput.wasReleased(MappedInputManager::Button::Up)) {
-    adjustPercent(kLargeStep);
-    return;
-  }
-
-  if (mappedInput.wasReleased(MappedInputManager::Button::Down)) {
-    adjustPercent(-kLargeStep);
-    return;
-  }
+  buttonNavigator.onPressAndContinuous({MappedInputManager::Button::Up}, [this] { adjustPercent(kLargeStep); });
+  buttonNavigator.onPressAndContinuous({MappedInputManager::Button::Down}, [this] { adjustPercent(-kLargeStep); });
 }
 
 void EpubReaderPercentSelectionActivity::renderScreen() {

src/activities/reader/EpubReaderPercentSelectionActivity.h

@@ -7,6 +7,7 @@
 
 #include "MappedInputManager.h"
 #include "activities/ActivityWithSubactivity.h"
+#include "util/ButtonNavigator.h"
 
 class EpubReaderPercentSelectionActivity final : public ActivityWithSubactivity {
  public:
@@ -31,6 +32,7 @@ class EpubReaderPercentSelectionActivity final : public ActivityWithSubactivity
   // FreeRTOS task and mutex for rendering.
   TaskHandle_t displayTaskHandle = nullptr;
   SemaphoreHandle_t renderingMutex = nullptr;
+  ButtonNavigator buttonNavigator;
 
   // Callback invoked when the user confirms a percent.
   const std::function<void(int)> onSelect;

src/activities/reader/XtcReaderChapterSelectionActivity.cpp

@@ -8,10 +8,6 @@
 #include "components/UITheme.h"
 #include "fontIds.h"
 
-namespace {
-constexpr int SKIP_PAGE_MS = 700;
-}  // namespace
-
 int XtcReaderChapterSelectionActivity::getPageItems() const {
   constexpr int lineHeight = 30;
 
@@ -78,13 +74,8 @@ void XtcReaderChapterSelectionActivity::onExit() {
 }
 
 void XtcReaderChapterSelectionActivity::loop() {
-  const bool prevReleased = mappedInput.wasReleased(MappedInputManager::Button::Up) ||
-                            mappedInput.wasReleased(MappedInputManager::Button::Left);
-  const bool nextReleased = mappedInput.wasReleased(MappedInputManager::Button::Down) ||
-                            mappedInput.wasReleased(MappedInputManager::Button::Right);
-
-  const bool skipPage = mappedInput.getHeldTime() > SKIP_PAGE_MS;
   const int pageItems = getPageItems();
+  const int totalItems = static_cast<int>(xtc->getChapters().size());
 
   if (mappedInput.wasReleased(MappedInputManager::Button::Confirm)) {
     const auto& chapters = xtc->getChapters();
@@ -93,29 +84,27 @@ void XtcReaderChapterSelectionActivity::loop() {
     }
   } else if (mappedInput.wasReleased(MappedInputManager::Button::Back)) {
     onGoBack();
-  } else if (prevReleased) {
-    const int total = static_cast<int>(xtc->getChapters().size());
-    if (total == 0) {
-      return;
-    }
-    if (skipPage) {
-      selectorIndex = ((selectorIndex / pageItems - 1) * pageItems + total) % total;
-    } else {
-      selectorIndex = (selectorIndex + total - 1) % total;
-    }
-    updateRequired = true;
-  } else if (nextReleased) {
-    const int total = static_cast<int>(xtc->getChapters().size());
-    if (total == 0) {
-      return;
-    }
-    if (skipPage) {
-      selectorIndex = ((selectorIndex / pageItems + 1) * pageItems) % total;
-    } else {
-      selectorIndex = (selectorIndex + 1) % total;
-    }
-    updateRequired = true;
   }
+
+  buttonNavigator.onNextRelease([this, totalItems] {
+    selectorIndex = ButtonNavigator::nextIndex(selectorIndex, totalItems);
+    updateRequired = true;
+  });
+
+  buttonNavigator.onPreviousRelease([this, totalItems] {
+    selectorIndex = ButtonNavigator::previousIndex(selectorIndex, totalItems);
+    updateRequired = true;
+  });
+
+  buttonNavigator.onNextContinuous([this, totalItems, pageItems] {
+    selectorIndex = ButtonNavigator::nextPageIndex(selectorIndex, totalItems, pageItems);
+    updateRequired = true;
+  });
+
+  buttonNavigator.onPreviousContinuous([this, totalItems, pageItems] {
+    selectorIndex = ButtonNavigator::previousPageIndex(selectorIndex, totalItems, pageItems);
+    updateRequired = true;
+  });
 }
 
 void XtcReaderChapterSelectionActivity::displayTaskLoop() {

src/activities/reader/XtcReaderChapterSelectionActivity.h

@@ -7,11 +7,13 @@
 #include <memory>
 
 #include "../Activity.h"
+#include "util/ButtonNavigator.h"
 
 class XtcReaderChapterSelectionActivity final : public Activity {
   std::shared_ptr<Xtc> xtc;
   TaskHandle_t displayTaskHandle = nullptr;
   SemaphoreHandle_t renderingMutex = nullptr;
+  ButtonNavigator buttonNavigator;
   uint32_t currentPage = 0;
   int selectorIndex = 0;
   bool updateRequired = false;