feat: 优化代码

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

@@ -26,6 +26,7 @@ abstract class HorizontalPageDelegate(pageView: PageView) : PageDelegate(pageVie
                         noNext = true
                         return true
                     }
+                    setDirection(Direction.PREV)
                     //上一页截图
                     bitmap = prevPage.screenshot()
                 } else {
@@ -34,6 +35,7 @@ abstract class HorizontalPageDelegate(pageView: PageView) : PageDelegate(pageVie
                         noNext = true
                         return true
                     }
+                    setDirection(Direction.NEXT)
                     //下一页截图
                     bitmap = nextPage.screenshot()
                 }

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

@@ -47,7 +47,9 @@ abstract class PageDelegate(protected val pageView: PageView) {
     protected var atTop: Boolean = false
     protected var atBottom: Boolean = false
 
-    private var snackBar: Snackbar? = null
+    private val snackBar: Snackbar by lazy {
+        pageView.snackbar("")
+    }
 
     private val scroller: Scroller by lazy {
         Scroller(
@@ -269,12 +271,14 @@ abstract class PageDelegate(protected val pageView: PageView) {
                     if (!hasNext()) {
                         return true
                     }
+                    setDirection(Direction.PREV)
                     //下一页截图
                     nextPage.screenshot()
                 } else {
                     if (!hasPrev()) {
                         return true
                     }
+                    setDirection(Direction.NEXT)
                     //上一页截图
                     prevPage.screenshot()
                 }
@@ -296,17 +300,11 @@ abstract class PageDelegate(protected val pageView: PageView) {
 
     fun hasPrev(): Boolean {
         //上一页的参数配置
-        setDirection(Direction.PREV)
         val hasPrev = pageView.pageFactory?.hasPrev() == true
         if (!hasPrev) {
-            snackBar ?: let {
-                snackBar = pageView.snackbar("没有上一页")
-            }
-            snackBar?.let {
-                if (!it.isShown) {
-                    it.setText("没有上一页")
-                    it.show()
-                }
+            if (!snackBar.isShown) {
+                snackBar.setText("没有上一页")
+                snackBar.show()
             }
         }
         return hasPrev
@@ -314,17 +312,11 @@ abstract class PageDelegate(protected val pageView: PageView) {
 
     fun hasNext(): Boolean {
         //进行下一页的配置
-        setDirection(Direction.NEXT)
         val hasNext = pageView.pageFactory?.hasNext() == true
         if (!hasNext) {
-            snackBar ?: let {
-                snackBar = pageView.snackbar("没有下一页")
-            }
-            snackBar?.let {
-                if (!it.isShown) {
-                    it.setText("没有下一页")
-                    it.show()
-                }
+            if (!snackBar.isShown) {
+                snackBar.setText("没有下一页")
+                snackBar.show()
             }
         }
         return hasNext

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

@@ -88,6 +88,7 @@ class ScrollPageDelegate(pageView: PageView) : PageDelegate(pageView) {
                         noNext = true
                         return true
                     }
+                    setDirection(Direction.PREV)
                     //上一页截图
                     bitmap = prevPage.screenshot()
                 }
@@ -101,6 +102,7 @@ class ScrollPageDelegate(pageView: PageView) : PageDelegate(pageView) {
                         noNext = true
                         return true
                     }
+                    setDirection(Direction.NEXT)
                     //下一页截图
                     bitmap = nextPage.screenshot()
                 }

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

@@ -3,9 +3,7 @@ package io.legado.app.ui.book.read.page.delegate
 import android.graphics.*
 import android.graphics.drawable.GradientDrawable
 import android.os.Build
-import android.view.MotionEvent
 import io.legado.app.ui.book.read.page.PageView
-import io.legado.app.utils.screenshot
 import kotlin.math.*
 
 @Suppress("DEPRECATION")
@@ -105,48 +103,6 @@ class SimulationPageDelegate(pageView: PageView) : HorizontalPageDelegate(pageVi
         }
     }
 
-    override fun onScroll(
-        e1: MotionEvent,
-        e2: MotionEvent,
-        distanceX: Float,
-        distanceY: Float
-    ): Boolean {
-        if (!isMoved) {
-            val event = e1.toAction(MotionEvent.ACTION_UP)
-            curPage.dispatchTouchEvent(event)
-            event.recycle()
-            if (abs(distanceX) > abs(distanceY)) {
-                if (distanceX < 0) {
-                    //如果上一页不存在
-                    if (!hasPrev()) {
-                        noNext = true
-                        return true
-                    }
-                    //上一页截图
-                    prevBitmap = prevPage.screenshot()
-                    curBitmap = curPage.screenshot()
-                } else {
-                    //如果不存在表示没有下一页了
-                    if (!hasNext()) {
-                        noNext = true
-                        return true
-                    }
-                    //下一页截图
-                    nextBitmap = nextPage.screenshot()
-                    curBitmap = curPage.screenshot()
-                }
-                isMoved = true
-            }
-        }
-        if (isMoved) {
-            isCancel = if (mDirection == Direction.NEXT) distanceX < 0 else distanceX > 0
-            isRunning = true
-            //设置触摸点
-            setTouchPoint(e2.x, e2.y)
-        }
-        return isMoved
-    }
-
     override fun setDirection(direction: Direction) {
         super.setDirection(direction)
         when (direction) {