优化导航栏

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

@@ -237,8 +237,7 @@ class ReadMenu @JvmOverloads constructor(
             override fun onAnimationEnd(animation: Animation) {
                 vw_menu_bg.onClick { runMenuOut() }
                 vwNavigationBar.layoutParams = vwNavigationBar.layoutParams.apply {
-                    height =
-                        if (SystemUtils.isNavigationBarExist(activity)) context.navigationBarHeight else 0
+                    height = activity!!.navigationBarHeight
                 }
                 if (LocalConfig.isFirstReadMenuShow) {
                     callBack.showReadMenuHelp()

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

@@ -85,7 +85,7 @@ class ContentView(context: Context) : FrameLayout(context) {
             vw_top_divider.visible(showHeaderLine)
             vw_bottom_divider.visible(showFooterLine)
             page_nv_bar.layoutParams = page_nv_bar.layoutParams.apply {
-                height = if (hideStatusBar) 0 else context.navigationBarHeight
+                height = if (hideNavigationBar) 0 else activity!!.navigationBarHeight
             }
             content_text_view.upVisibleRect()
         }

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

@@ -21,3 +21,12 @@ fun Activity.getSize(): DisplayMetrics {
     }
     return displayMetrics
 }
+
+val Activity.navigationBarHeight: Int
+    get() {
+        if (SystemUtils.isNavigationBarExist(this)) {
+            val resourceId = resources.getIdentifier("navigation_bar_height", "dimen", "android")
+            return resources.getDimensionPixelSize(resourceId)
+        }
+        return 0
+    }