Track C1 ReaderRenderModel Implementation Plan

For agentic workers: REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (- [ ]) syntax for tracking.

Goal: 在不改变旧 ReadView 渲染行为的前提下，暴露可供后续 Compose 阅读表面消费的只读结构渲染流与高频 viewport 流。

Architecture: ReaderRenderStateStore 维护两个彼此独立的 StateFlow：低频 ReaderRenderModel 聚合 LegacyReaderSnapshot、三页绘制数据、页索引、选择、朗读高亮与 loading；高频 ReaderRenderViewport 只承载尺寸、触点、方向和归一化动画进度。ReadBookController 负责从现有 ReadBook/ReadView 真源取样，旧 View 只在已有状态变化点通知控制器，不转移状态所有权，也不改变任何绘制调用顺序。

Tech Stack: Kotlin、StateFlow、kotlinx.collections.immutable、Android View、Robolectric/JUnit 4。

Task 1: 定义并测试只读渲染状态容器

Files:

Create: app/src/main/java/io/legado/app/ui/book/read/ReaderRenderModel.kt
Create: app/src/test/java/io/legado/app/ui/book/read/ReaderRenderStateStoreTest.kt

[ ] Step 1: 写低频结构态与高频 viewport 相互独立的失败测试

@RunWith(RobolectricTestRunner::class)
class ReaderRenderStateStoreTest {
@Test
fun `viewport updates do not replace structural model`() {
    val store = ReaderRenderStateStore(LegacyReaderSnapshot(bookUrl = "book"))
    val structural = store.model.value

    store.publishViewport(
        width = 100,
        height = 200,
        startX = 0f,
        startY = 0f,
        touchX = 50f,
        touchY = 0f,
        direction = PageDirection.NEXT,
        isAnimationRunning = true,
    )

    assertSame(structural, store.model.value)
    assertEquals(0.5f, store.viewport.value.animationProgress, 0f)
}
}

[ ] Step 2: 运行测试并确认因 ReaderRenderStateStore 尚不存在而失败

Run: ./gradlew --no-daemon :app:testAppDebugUnitTest --tests 'io.legado.app.ui.book.read.ReaderRenderStateStoreTest'

Expected: Kotlin 编译失败，提示 Unresolved reference 'ReaderRenderStateStore'。

[ ] Step 3: 写三页、选择、朗读高亮、loading 与会话更新的失败测试

@Test
fun `structure publish snapshots render inputs`() {
val current = TextPage(index = 4, text = "current", chapterIndex = 2)
val line = TextLine().apply { isReadAloud = true }
current.addLine(line)
val mutableStart = TextPos(0, 1, 2)
val mutableEnd = TextPos(0, 1, 5)
val store = ReaderRenderStateStore()

store.publishStructure(
    previousPage = TextPage(index = 3),
    currentPage = current,
    nextPage = TextPage(index = 5),
    durPageIndex = 4,
    selectionStart = mutableStart,
    selectionEnd = mutableEnd,
    message = "Loading…",
    isLoading = true,
)
mutableStart.lineIndex = 9

val model = store.model.value
assertEquals(4, model.durPageIndex)
assertEquals(1, model.selection?.start?.lineIndex)
assertEquals(0, model.readAloudHighlights.single().firstLineIndex)
assertTrue(model.isLoading)
}

@Test
fun `session updates preserve render pages`() {
val store = ReaderRenderStateStore()
val current = TextPage(index = 1)
store.publishStructure(currentPage = current, durPageIndex = 1)

store.publishSession(LegacyReaderSnapshot(bookUrl = "updated", chapterIndex = 3))

assertEquals("updated", store.model.value.session.bookUrl)
assertSame(current, store.model.value.currentPage?.page)
}

[ ] Step 4: 实现最小只读模型与双 StateFlow 容器

@Stable
class ReaderRenderPage internal constructor(
val page: TextPage,
val revision: Long,
) {
override fun equals(other: Any?): Boolean =
    other is ReaderRenderPage && page === other.page && revision == other.revision

override fun hashCode(): Int = 31 * System.identityHashCode(page) + revision.hashCode()
}

@Stable
data class ReaderTextPosition(
val relativePage: Int,
val lineIndex: Int,
val columnIndex: Int,
)

@Stable
data class ReaderSelection(
val start: ReaderTextPosition,
val end: ReaderTextPosition,
)

@Stable
data class ReaderReadAloudHighlight(
val relativePage: Int,
val firstLineIndex: Int,
val lastLineIndex: Int,
)

@Stable
data class ReaderRenderModel(
val session: LegacyReaderSnapshot = LegacyReaderSnapshot(),
val previousPage: ReaderRenderPage? = null,
val currentPage: ReaderRenderPage? = null,
val nextPage: ReaderRenderPage? = null,
val durPageIndex: Int = 0,
val selection: ReaderSelection? = null,
val readAloudHighlights: ImmutableList<ReaderReadAloudHighlight> = persistentListOf(),
val message: String? = null,
val isLoading: Boolean = false,
)

@Stable
data class ReaderRenderViewport(
val width: Int = 0,
val height: Int = 0,
val startX: Float = 0f,
val startY: Float = 0f,
val touchX: Float = 0f,
val touchY: Float = 0f,
val direction: PageDirection = PageDirection.NONE,
val isAnimationRunning: Boolean = false,
val animationProgress: Float = 0f,
)

internal class ReaderRenderStateStore(
initialSession: LegacyReaderSnapshot = LegacyReaderSnapshot(),
) {
private val _model = MutableStateFlow(ReaderRenderModel(session = initialSession))
val model = _model.asStateFlow()
private val _viewport = MutableStateFlow(ReaderRenderViewport())
val viewport = _viewport.asStateFlow()

fun publishSession(session: LegacyReaderSnapshot) {
    _model.update { it.copy(session = session) }
}

private var revision = 0L

fun publishStructure(
    previousPage: TextPage? = null,
    currentPage: TextPage? = null,
    nextPage: TextPage? = null,
    durPageIndex: Int = 0,
    selectionStart: TextPos? = null,
    selectionEnd: TextPos? = null,
    message: String? = null,
    isLoading: Boolean = false,
) {
    revision++
    val pages = listOf(-1 to previousPage, 0 to currentPage, 1 to nextPage)
    _model.update { current ->
        current.copy(
            previousPage = previousPage?.let { ReaderRenderPage(it, revision) },
            currentPage = currentPage?.let { ReaderRenderPage(it, revision) },
            nextPage = nextPage?.let { ReaderRenderPage(it, revision) },
            durPageIndex = durPageIndex,
            selection = if (
                selectionStart?.isSelected() == true && selectionEnd?.isSelected() == true
            ) {
                ReaderSelection(
                    start = selectionStart.toReaderTextPosition(),
                    end = selectionEnd.toReaderTextPosition(),
                )
            } else {
                null
            },
            readAloudHighlights = pages.mapNotNull { (relativePage, page) ->
                val indices = page?.lines?.indices?.filter { page.lines[it].isReadAloud }
                    .orEmpty()
                if (indices.isEmpty()) null else ReaderReadAloudHighlight(
                    relativePage = relativePage,
                    firstLineIndex = indices.first(),
                    lastLineIndex = indices.last(),
                )
            }.toImmutableList(),
            message = message,
            isLoading = isLoading,
        )
    }
}

fun publishViewport(
    width: Int,
    height: Int,
    startX: Float,
    startY: Float,
    touchX: Float,
    touchY: Float,
    direction: PageDirection,
    isAnimationRunning: Boolean,
) {
    val xProgress = if (width > 0) abs(touchX - startX) / width else 0f
    val yProgress = if (height > 0) abs(touchY - startY) / height else 0f
    _viewport.value = ReaderRenderViewport(
        width = width,
        height = height,
        startX = startX,
        startY = startY,
        touchX = touchX,
        touchY = touchY,
        direction = direction,
        isAnimationRunning = isAnimationRunning,
        animationProgress = max(xProgress, yProgress).coerceIn(0f, 1f),
    )
}
}

[ ] Step 5: 运行聚焦测试，确认全部通过

Run: ./gradlew --no-daemon :app:testAppDebugUnitTest --tests 'io.legado.app.ui.book.read.ReaderRenderStateStoreTest'

Expected: BUILD SUCCESSFUL，所有 ReaderRenderStateStoreTest 用例通过。

[ ] Step 6: 提交状态模型任务

git add app/src/main/java/io/legado/app/ui/book/read/ReaderRenderModel.kt app/src/test/java/io/legado/app/ui/book/read/ReaderRenderStateStoreTest.kt
git commit -m "feat(Track C): 抽取阅读器只读渲染状态"

Task 2: 从旧 ReadView 真源并行发布渲染状态

Files:

Modify: app/src/main/java/io/legado/app/ui/book/read/ReadBookController.kt
Modify: app/src/main/java/io/legado/app/ui/book/read/page/ReadView.kt
Modify: app/src/main/java/io/legado/app/ui/book/read/page/PageView.kt
Modify: app/src/main/java/io/legado/app/ui/book/read/page/ContentTextView.kt
Modify: app/src/main/java/io/legado/app/ui/book/read/page/delegate/PageDelegate.kt
Modify: docs/dev/track-c-compose-reader-plan.md
Test: app/src/test/java/io/legado/app/ui/book/read/ReaderRenderStateStoreTest.kt

[ ] Step 1: 补充相同 TextPage 重发时 revision 递增的回归测试

@Test
fun `republishing same mutable page advances render revision`() {
val store = ReaderRenderStateStore()
val page = TextPage(index = 1)
store.publishStructure(currentPage = page, durPageIndex = 1)
val first = store.model.value.currentPage!!

page.hasReadAloudSpan = true
store.publishStructure(currentPage = page, durPageIndex = 1)

val second = store.model.value.currentPage!!
assertSame(page, second.page)
assertTrue(second.revision > first.revision)
assertNotEquals(first, second)
}

[ ] Step 2: 运行测试确认 identity + revision 契约继续成立

Run: ./gradlew --no-daemon :app:testAppDebugUnitTest --tests 'io.legado.app.ui.book.read.ReaderRenderStateStoreTest.republishing same mutable page advances render revision'

Expected: BUILD SUCCESSFUL；相同可变页的后续发布具有更大的 revision，且不触发 TextPage 深层 equality。

[ ] Step 3: 保持页面包装的 identity + revision 相等语义，不在接线层复制 TextPage

@Stable
class ReaderRenderPage internal constructor(
val page: TextPage,
val revision: Long,
) {
override fun equals(other: Any?): Boolean =
    other is ReaderRenderPage && page === other.page && revision == other.revision

override fun hashCode(): Int = 31 * System.identityHashCode(page) + revision.hashCode()
}

[ ] Step 4: 在旧 View 的既有变更点仅增加取样通知

// ReadView.CallBack
fun onRenderStructureChanged()
fun onRenderViewportChanged()

// ReadView
internal fun notifyRenderViewportChanged() = callBack.onRenderViewportChanged()

// Existing methods keep their original behavior/order, then notify:
// onSizeChanged / setStartPoint / setTouchPoint / upPageAnim -> viewport
// upContent / onLayoutPageCompleted -> structure

ContentTextView/PageView 只增加返回 TextPos.copy() 的选择快照 getter；不得把内部可变 TextPos 直接放进状态。PageDelegate.isRunning、isStarted 和 setDirection 的 setter 在原赋值后通知 viewport，使动画停止也能发出最终状态。

[ ] Step 5: 在 ReadBookController 暴露双只读 Flow 并从现有真源取样

private val renderStateStore = ReaderRenderStateStore(ReadBook.snapshot.value)
val readerRenderModel = renderStateStore.model
val readerRenderViewport = renderStateStore.viewport

init {
activity.lifecycleScope.launch {
    ReadBook.snapshot.collect(renderStateStore::publishSession)
}
}

override fun onRenderStructureChanged() = publishRenderStructure()
override fun onRenderViewportChanged() = publishRenderViewport()

publishRenderStructure() 读取 readView.prevPage/curPage/nextPage.textPage、ReadBook.durPageIndex、选择副本、ReadBook.msg 与当前 loading 判定；publishRenderViewport() 读取 View 尺寸、触点、delegate 方向/运行状态。onRefsReady 首次发布两条流，upSelectedStart、upSelectedEnd、onCancelSelect 在原 UI 更新后重发结构态。

Step 6: 更新 C1 文档状态并运行测试与编译

Run: ./gradlew --no-daemon :app:testAppDebugUnitTest --tests 'io.legado.app.ui.book.read.ReaderRenderStateStoreTest'

Run: ./gradlew --no-daemon :app:compileAppDebugKotlin

Expected: 两条命令均 BUILD SUCCESSFUL；旧 ReadView 仍是唯一绘制者，代码中没有新增 Compose Canvas、pointerInput 或 feature flag。

[ ] Step 7: 停止编译进程并提交接线任务

./gradlew --stop
git add app/src/main/java/io/legado/app/ui/book/read/ReadBookController.kt app/src/main/java/io/legado/app/ui/book/read/page/ReadView.kt app/src/main/java/io/legado/app/ui/book/read/page/PageView.kt app/src/main/java/io/legado/app/ui/book/read/page/ContentTextView.kt app/src/main/java/io/legado/app/ui/book/read/page/delegate/PageDelegate.kt docs/dev/track-c-compose-reader-plan.md app/src/test/java/io/legado/app/ui/book/read/ReaderRenderStateStoreTest.kt
git commit -m "refactor(Track C): 并行发布旧阅读器渲染状态"

2026-07-21-track-c1-reader-render-model.md 13 KB Постоянная ссылка История Исходник

Track C1 ReaderRenderModel Implementation Plan

Task 1: 定义并测试只读渲染状态容器

Task 2: 从旧 ReadView 真源并行发布渲染状态

2026-07-21-track-c1-reader-render-model.md 13 KB

Постоянная ссылка История Исходник