优化

app/src/main/java/io/legado/app/ui/book/read/page/ContentTextView.kt

@@ -6,7 +6,6 @@ import android.graphics.Paint
 import android.util.AttributeSet
 import android.view.MotionEvent
 import android.view.View
-import androidx.core.graphics.withTranslation
 import io.legado.app.R
 import io.legado.app.data.entities.Bookmark
 import io.legado.app.help.config.AppConfig
@@ -23,6 +22,7 @@ import io.legado.app.ui.book.read.page.entities.column.TextColumn
 import io.legado.app.ui.book.read.page.provider.ChapterProvider
 import io.legado.app.ui.book.read.page.provider.TextPageFactory
 import io.legado.app.ui.widget.dialog.PhotoDialog
+import io.legado.app.utils.PictureMirror
 import io.legado.app.utils.activity
 import io.legado.app.utils.getCompatColor
 import io.legado.app.utils.showDialogFragment
@@ -102,25 +102,18 @@ class ContentTextView(context: Context, attrs: AttributeSet?) : View(context, at
      */
     private fun drawPage(canvas: Canvas) {
         var relativeOffset = relativeOffset(0)
-        val view = this
+        textPage.draw(this, canvas, relativeOffset)
-        canvas.withTranslation(0f, relativeOffset) {
-            textPage.draw(view, this)
-        }
         if (!callBack.isScroll) return
         //滚动翻页
         if (!pageFactory.hasNext()) return
         val textPage1 = relativePage(1)
         relativeOffset = relativeOffset(1)
-        canvas.withTranslation(0f, relativeOffset) {
+        textPage1.draw(this, canvas, relativeOffset)
-            textPage1.draw(view, this)
-        }
         if (!pageFactory.hasNextPlus()) return
         relativeOffset = relativeOffset(2)
         if (relativeOffset < ChapterProvider.visibleHeight) {
             val textPage2 = relativePage(2)
-            canvas.withTranslation(0f, relativeOffset) {
+            textPage2.draw(this, canvas, relativeOffset)
-                textPage2.draw(view, this)
-            }
         }
     }
 
@@ -167,7 +160,9 @@ class ContentTextView(context: Context, attrs: AttributeSet?) : View(context, at
     }
 
     fun submitPreRenderTask() {
-        renderThread.submit(renderRunnable)
+        if (PictureMirror.atLeastApi23) {
+            renderThread.submit(renderRunnable)
+        }
     }
 
     private fun preRenderPage() {

app/src/main/java/io/legado/app/ui/book/read/page/entities/TextLine.kt

@@ -121,7 +121,7 @@ data class TextLine(
         return visible
     }
 
-    fun draw(view: ContentTextView, canvas: Canvas?) {
+    fun draw(view: ContentTextView, canvas: Canvas) {
         pictureMirror.draw(canvas, view.width, height.toInt()) {
             drawTextLine(view, this)
         }

app/src/main/java/io/legado/app/ui/book/read/page/entities/TextPage.kt

@@ -45,6 +45,7 @@ data class TextPage(
     var isMsgPage: Boolean = false
     var pictureMirror: PictureMirror = PictureMirror()
     var doublePage = false
+    var paddingTop = 0
 
     val paragraphs by lazy {
         paragraphsInternal
@@ -159,6 +160,7 @@ data class TextPage(
                 addLine(textLine)
             }
             height = ChapterProvider.visibleHeight.toFloat()
+            invalidate()
         }
         return this
     }
@@ -180,7 +182,8 @@ data class TextPage(
     fun upPageAloudSpan(aloudSpanStart: Int) {
         removePageAloudSpan()
         var lineStart = 0
-        for ((index, textLine) in textLines.withIndex()) {
+        for (index in textLines.indices) {
+            val textLine = textLines[index]
             val lineLength = textLine.text.length + if (textLine.isParagraphEnd) 1 else 0
             if (aloudSpanStart > lineStart && aloudSpanStart < lineStart + lineLength) {
                 for (i in index - 1 downTo 0) {
@@ -263,16 +266,19 @@ data class TextPage(
         return null
     }
 
-    fun draw(view: ContentTextView, canvas: Canvas?) {
+    fun draw(view: ContentTextView, canvas: Canvas, relativeOffset: Float) {
-        pictureMirror.drawLocked(canvas, view.width, height.toInt()) {
+        val height = height.toInt()
-            drawPage(view, this)
+        canvas.withTranslation(0f, relativeOffset + paddingTop) {
+            pictureMirror.drawLocked(canvas, view.width, height) {
+                drawPage(view, this)
+            }
         }
     }
 
     private fun drawPage(view: ContentTextView, canvas: Canvas) {
         for (i in lines.indices) {
             val line = lines[i]
-            canvas.withTranslation(0f, line.lineTop) {
+            canvas.withTranslation(0f, line.lineTop - paddingTop) {
                 line.draw(view, this)
             }
         }
@@ -280,7 +286,9 @@ data class TextPage(
 
     fun preRender(view: ContentTextView): Boolean {
         if (!pictureMirror.isDirty) return false
-        draw(view, null)
+        pictureMirror.drawLocked(null, view.width, height.toInt()) {
+            drawPage(view, this)
+        }
         return true
     }
 

app/src/main/java/io/legado/app/ui/book/read/page/provider/ChapterProvider.kt

@@ -290,6 +290,7 @@ object ChapterProvider {
             item.chapterSize = chapterSize
             item.title = displayTitle
             item.doublePage = doublePage
+            item.paddingTop = paddingTop
             item.upLinesPosition()
         }
 

app/src/main/java/io/legado/app/ui/book/read/page/provider/TextPageFactory.kt

@@ -12,7 +12,7 @@ class TextPageFactory(dataSource: DataSource) : PageFactory<TextPage>(dataSource
     }
 
     override fun hasNext(): Boolean = with(dataSource) {
-        return hasNextChapter() || currentChapter?.isLastIndex(pageIndex) != true
+        return hasNextChapter() || (currentChapter != null && currentChapter?.isLastIndex(pageIndex) != true)
     }
 
     override fun hasNextPlus(): Boolean = with(dataSource) {
@@ -85,14 +85,12 @@ class TextPageFactory(dataSource: DataSource) : PageFactory<TextPage>(dataSource
                 return@with TextPage(text = it).format()
             }
             currentChapter?.let {
+                val pageIndex = pageIndex
                 if (pageIndex < it.pageSize - 1) {
                     return@with it.getPage(pageIndex + 1)?.removePageAloudSpan()
                         ?: TextPage(title = it.title).format()
                 }
             }
-            if (!hasNextChapter()) {
-                return@with TextPage(text = "")
-            }
             nextChapter?.let {
                 return@with it.getPage(0)?.removePageAloudSpan()
                     ?: TextPage(title = it.title).format()
@@ -105,8 +103,9 @@ class TextPageFactory(dataSource: DataSource) : PageFactory<TextPage>(dataSource
             ReadBook.msg?.let {
                 return@with TextPage(text = it).format()
             }
-            if (pageIndex > 0) {
+            currentChapter?.let {
-                currentChapter?.let {
+                val pageIndex = pageIndex
+                if (pageIndex > 0) {
                     return@with it.getPage(pageIndex - 1)?.removePageAloudSpan()
                         ?: TextPage(title = it.title).format()
                 }
@@ -121,6 +120,7 @@ class TextPageFactory(dataSource: DataSource) : PageFactory<TextPage>(dataSource
     override val nextPlusPage: TextPage
         get() = with(dataSource) {
             currentChapter?.let {
+                val pageIndex = pageIndex
                 if (pageIndex < it.pageSize - 2) {
                     return@with it.getPage(pageIndex + 2)?.removePageAloudSpan()
                         ?: TextPage(title = it.title).format()
@@ -133,7 +133,6 @@ class TextPageFactory(dataSource: DataSource) : PageFactory<TextPage>(dataSource
                     return@with nc.getPage(1)?.removePageAloudSpan()
                         ?: TextPage(text = "继续滑动以加载下一章…").format()
                 }
-
             }
             return TextPage().format()
         }

app/src/main/java/io/legado/app/utils/PictureMirror.kt

@@ -23,15 +23,11 @@ class PictureMirror {
         block: Canvas.() -> Unit
     ) {
         if (atLeastApi23) {
-            if (picture == null) {
+            if (picture == null || lock == null) {
                 synchronized(this) {
                     if (picture == null) {
                         picture = Picture()
                     }
-                }
-            }
-            if (lock == null) {
-                synchronized(this) {
                     if (lock == null) {
                         lock = ReentrantLock()
                     }