优化

app/src/main/java/io/legado/app/App.kt

@@ -86,4 +86,8 @@ class App : MultiDexApplication() {
         }
     }
 
+    companion object {
+        var navigationBarHeight = 0
+    }
+
 }

app/src/main/java/io/legado/app/base/BaseActivity.kt

@@ -12,6 +12,7 @@ import android.view.View
 import android.widget.FrameLayout
 import androidx.appcompat.app.AppCompatActivity
 import androidx.viewbinding.ViewBinding
+import io.legado.app.App
 import io.legado.app.R
 import io.legado.app.constant.AppConst
 import io.legado.app.constant.PreferKey
@@ -99,6 +100,13 @@ abstract class BaseActivity<VB : ViewBinding>(
         observeLiveBus()
     }
 
+    override fun onWindowFocusChanged(hasFocus: Boolean) {
+        super.onWindowFocusChanged(hasFocus)
+        if (hasFocus) {
+            App.navigationBarHeight = navigationBarHeight
+        }
+    }
+
     override fun onMultiWindowModeChanged(isInMultiWindowMode: Boolean, newConfig: Configuration?) {
         super.onMultiWindowModeChanged(isInMultiWindowMode, newConfig)
         findViewById<TitleBar>(R.id.title_bar)

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

@@ -7,7 +7,6 @@ import android.content.res.Configuration
 import android.os.Bundle
 import android.os.Handler
 import android.os.Looper
-import android.util.Log
 import android.view.*
 import android.view.ViewGroup.LayoutParams.WRAP_CONTENT
 import androidx.activity.result.contract.ActivityResultContracts
@@ -151,7 +150,6 @@ class ReadBookActivity : ReadBookBaseActivity(),
 
     override fun onWindowFocusChanged(hasFocus: Boolean) {
         super.onWindowFocusChanged(hasFocus)
-        Log.d("navigationBarHeight", navigationBarHeight.toString())
         upSystemUiVisibility()
     }
 

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

@@ -7,6 +7,7 @@ import android.view.LayoutInflater
 import android.widget.FrameLayout
 import androidx.core.view.isGone
 import androidx.core.view.isInvisible
+import io.legado.app.App
 import io.legado.app.R
 import io.legado.app.base.BaseActivity
 import io.legado.app.constant.AppConst.timeFormat
@@ -86,7 +87,7 @@ class PageView(context: Context) : FrameLayout(context) {
             pageNvBar.layoutParams = pageNvBar.layoutParams.apply {
                 height =
                     if (it.hideNavigationBar) 0
-                    else activity?.navigationBarHeight ?: 0
+                    else App.navigationBarHeight
             }
         }
         contentTextView.upVisibleRect()