Files
crosspoint-reader-mod/src/activities/reader/XtcReaderChapterSelectionActivity.cpp
Xuan-Son Nguyen c4fc4effbd refactor: implement ActivityManager (#1016)
## Summary

Ref comment:
https://github.com/crosspoint-reader/crosspoint-reader/pull/1010#pullrequestreview-3828854640

This PR introduces `ActivityManager`, which mirrors the same concept of
Activity in Android, where an activity represents a single screen of the
UI. The manager is responsible for launching activities, and ensuring
that only one activity is active at a time.

Main differences from Android's ActivityManager:
- No concept of Bundle or Intent extras
- No onPause/onResume, since we don't have a concept of background
activities
- onActivityResult is implemented via a callback instead of a separate
method, for simplicity

## Key changes

- Single `renderTask` shared across all activities
- No more sub-activity, we manage them using a stack; Results can be
passed via `startActivityForResult` and `setResult`
- Activity can call `finish()` to destroy themself, but the actual
deletion will be handled by `ActivityManager` to avoid `delete this`
pattern

As a bonus: the manager will automatically call `requestUpdate()` when
returning from another activity

## Example usage

**BEFORE**:

```cpp
// caller
    enterNewActivity(new WifiSelectionActivity(renderer, mappedInput,
                                               [this](const bool connected) { onWifiSelectionComplete(connected); }));

// subactivity
  onComplete(true); // will eventually call exitActivity(), which deletes the caller instance (dangerous behavior)
``` 

**AFTER**: (mirrors the `startActivityForResult` and `setResult` from
android)

```cpp
// caller
  startActivityForResult(new NetworkModeSelectionActivity(renderer, mappedInput),
                         [this](const ActivityResult& result) { onNetworkModeSelected(result.selectedNetworkMode); });

// subactivity
  ActivityResult result;
  result.isCancelled = false;
  result.selectedNetworkMode = mode;
  setResult(result);
  finish(); // signals to ActivityManager to go back to last activity AFTER this function returns
```

TODO:
- [x] Reconsider if the `Intent` is really necessary or it should be
removed (note: it's inspired by
[Intent](https://developer.android.com/guide/components/intents-common)
from Android API) ==> I decided to keep this pattern fr clarity
- [x] Verify if behavior is still correct (i.e. back from sub-activity)
- [x] Refactor the `ActivityWithSubactivity` to just simple `Activity`
--> We are using a stack for keeping track of sub-activity now
- [x] Use single task for rendering --> avoid allocating 8KB stack per
activity
- [x] Implement the idea of [Activity
result](https://developer.android.com/training/basics/intents/result)
--> Allow sub-activity like Wifi to report back the status (connected,
failed, etc)

---

### AI Usage

While CrossPoint doesn't have restrictions on AI tools in contributing,
please be transparent about their usage as it
helps set the right context for reviewers.

Did you use AI tools to help write this code? **PARTIALLY**, some
repetitive migrations are done by Claude, but I'm the one how ultimately
approve it

---------

Co-authored-by: Zach Nelson <zach@zdnelson.com>
2026-02-27 00:32:40 -06:00

141 lines
5.4 KiB
C++

#include "XtcReaderChapterSelectionActivity.h"
#include <GfxRenderer.h>
#include <I18n.h>
#include <algorithm>
#include "MappedInputManager.h"
#include "components/UITheme.h"
#include "fontIds.h"
int XtcReaderChapterSelectionActivity::getPageItems() const {
constexpr int lineHeight = 30;
const int screenHeight = renderer.getScreenHeight();
const auto orientation = renderer.getOrientation();
// In inverted portrait, the hint row is drawn near the logical top.
// Reserve vertical space so the list starts below the hints.
const bool isPortraitInverted = orientation == GfxRenderer::Orientation::PortraitInverted;
const int hintGutterHeight = isPortraitInverted ? 50 : 0;
const int startY = 60 + hintGutterHeight;
const int availableHeight = screenHeight - startY - lineHeight;
// Clamp to at least one item to prevent empty page math.
return std::max(1, availableHeight / lineHeight);
}
int XtcReaderChapterSelectionActivity::findChapterIndexForPage(uint32_t page) const {
if (!xtc) {
return 0;
}
const auto& chapters = xtc->getChapters();
for (size_t i = 0; i < chapters.size(); i++) {
if (page >= chapters[i].startPage && page <= chapters[i].endPage) {
return static_cast<int>(i);
}
}
return 0;
}
void XtcReaderChapterSelectionActivity::onEnter() {
Activity::onEnter();
if (!xtc) {
return;
}
selectorIndex = findChapterIndexForPage(currentPage);
requestUpdate();
}
void XtcReaderChapterSelectionActivity::onExit() { Activity::onExit(); }
void XtcReaderChapterSelectionActivity::loop() {
const int pageItems = getPageItems();
const int totalItems = static_cast<int>(xtc->getChapters().size());
if (mappedInput.wasReleased(MappedInputManager::Button::Confirm)) {
const auto& chapters = xtc->getChapters();
if (!chapters.empty() && selectorIndex >= 0 && selectorIndex < static_cast<int>(chapters.size())) {
setResult(PageResult{chapters[selectorIndex].startPage});
finish();
}
} else if (mappedInput.wasReleased(MappedInputManager::Button::Back)) {
ActivityResult result;
result.isCancelled = true;
setResult(std::move(result));
finish();
}
buttonNavigator.onNextRelease([this, totalItems] {
selectorIndex = ButtonNavigator::nextIndex(selectorIndex, totalItems);
requestUpdate();
});
buttonNavigator.onPreviousRelease([this, totalItems] {
selectorIndex = ButtonNavigator::previousIndex(selectorIndex, totalItems);
requestUpdate();
});
buttonNavigator.onNextContinuous([this, totalItems, pageItems] {
selectorIndex = ButtonNavigator::nextPageIndex(selectorIndex, totalItems, pageItems);
requestUpdate();
});
buttonNavigator.onPreviousContinuous([this, totalItems, pageItems] {
selectorIndex = ButtonNavigator::previousPageIndex(selectorIndex, totalItems, pageItems);
requestUpdate();
});
}
void XtcReaderChapterSelectionActivity::render(RenderLock&&) {
renderer.clearScreen();
const auto pageWidth = renderer.getScreenWidth();
const auto orientation = renderer.getOrientation();
// Landscape orientation: reserve a horizontal gutter for button hints.
const bool isLandscapeCw = orientation == GfxRenderer::Orientation::LandscapeClockwise;
const bool isLandscapeCcw = orientation == GfxRenderer::Orientation::LandscapeCounterClockwise;
// Inverted portrait: reserve vertical space for hints at the top.
const bool isPortraitInverted = orientation == GfxRenderer::Orientation::PortraitInverted;
const int hintGutterWidth = (isLandscapeCw || isLandscapeCcw) ? 30 : 0;
// Landscape CW places hints on the left edge; CCW keeps them on the right.
const int contentX = isLandscapeCw ? hintGutterWidth : 0;
const int contentWidth = pageWidth - hintGutterWidth;
const int hintGutterHeight = isPortraitInverted ? 50 : 0;
const int contentY = hintGutterHeight;
const int pageItems = getPageItems();
// Manual centering to honor content gutters.
const int titleX =
contentX + (contentWidth - renderer.getTextWidth(UI_12_FONT_ID, tr(STR_SELECT_CHAPTER), EpdFontFamily::BOLD)) / 2;
renderer.drawText(UI_12_FONT_ID, titleX, 15 + contentY, tr(STR_SELECT_CHAPTER), true, EpdFontFamily::BOLD);
const auto& chapters = xtc->getChapters();
if (chapters.empty()) {
// Center the empty state within the gutter-safe content region.
const int emptyX = contentX + (contentWidth - renderer.getTextWidth(UI_10_FONT_ID, tr(STR_NO_CHAPTERS))) / 2;
renderer.drawText(UI_10_FONT_ID, emptyX, 120 + contentY, tr(STR_NO_CHAPTERS));
renderer.displayBuffer();
return;
}
const auto pageStartIndex = selectorIndex / pageItems * pageItems;
// Highlight only the content area, not the hint gutters.
renderer.fillRect(contentX, 60 + contentY + (selectorIndex % pageItems) * 30 - 2, contentWidth - 1, 30);
for (int i = pageStartIndex; i < static_cast<int>(chapters.size()) && i < pageStartIndex + pageItems; i++) {
const auto& chapter = chapters[i];
const char* title = chapter.name.empty() ? tr(STR_UNNAMED) : chapter.name.c_str();
renderer.drawText(UI_10_FONT_ID, contentX + 20, 60 + contentY + (i % pageItems) * 30, title, i != selectorIndex);
}
// Skip button hints in landscape CW mode (they overlap content)
if (renderer.getOrientation() != GfxRenderer::LandscapeClockwise) {
const auto labels = mappedInput.mapLabels(tr(STR_BACK), tr(STR_SELECT), tr(STR_DIR_UP), tr(STR_DIR_DOWN));
GUI.drawButtonHints(renderer, labels.btn1, labels.btn2, labels.btn3, labels.btn4);
}
renderer.displayBuffer();
}