diff --git a/app/src/main/java/io/legado/app/base/BaseActivity.kt b/app/src/main/java/io/legado/app/base/BaseActivity.kt
index c3be3ac14..87ec5121e 100644
--- a/app/src/main/java/io/legado/app/base/BaseActivity.kt
+++ b/app/src/main/java/io/legado/app/base/BaseActivity.kt
@@ -1,12 +1,14 @@
 package io.legado.app.base
 
+import android.graphics.Color
 import android.os.Bundle
 import android.view.Menu
 import android.view.MenuItem
+import android.view.View
+import android.view.WindowManager
 import androidx.appcompat.app.AppCompatActivity
 import androidx.appcompat.view.menu.MenuBuilder
 import androidx.appcompat.view.menu.MenuItemImpl
-import androidx.core.content.ContextCompat
 import androidx.core.view.forEach
 import androidx.lifecycle.ViewModel
 import io.legado.app.R
@@ -14,6 +16,8 @@ import io.legado.app.lib.theme.ColorUtils
 import io.legado.app.lib.theme.DrawableUtils
 import io.legado.app.lib.theme.ThemeStore
 import io.legado.app.lib.theme.getPrimaryTextColor
+import io.legado.app.utils.getCompatColor
+
 
 abstract class BaseActivity<VM : ViewModel> : AppCompatActivity() {
 
@@ -23,6 +27,7 @@ abstract class BaseActivity<VM : ViewModel> : AppCompatActivity() {
 
     override fun onCreate(savedInstanceState: Bundle?) {
         initTheme()
+        setupSystemBar()
         super.onCreate(savedInstanceState)
         setContentView(layoutID)
         onViewModelCreated(viewModel, savedInstanceState)
@@ -37,8 +42,8 @@ abstract class BaseActivity<VM : ViewModel> : AppCompatActivity() {
             }
             val bool = onCompatCreateOptionsMenu(it)
             val primaryTextColor = getPrimaryTextColor(ColorUtils.isColorLight(ThemeStore.primaryColor(this)))
-            val defaultTextColor = ContextCompat.getColor(this, R.color.tv_text_default)
-            menu.forEach {item ->
+            val defaultTextColor = getCompatColor(R.color.tv_text_default)
+            menu.forEach { item ->
                 (item as MenuItemImpl).let { impl ->
                     //overflow：展开的item
                     DrawableUtils.setTint(
@@ -77,4 +82,11 @@ abstract class BaseActivity<VM : ViewModel> : AppCompatActivity() {
             setTheme(R.style.AppTheme_Dark)
         }
     }
+
+    protected fun setupSystemBar() {
+        window.clearFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS or WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION)
+        window.decorView.systemUiVisibility = View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN or View.SYSTEM_UI_FLAG_LAYOUT_STABLE
+        window.addFlags(WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS)
+        window.statusBarColor = Color.TRANSPARENT
+    }
 }
\ No newline at end of file
diff --git a/app/src/main/java/io/legado/app/ui/main/MainActivity.kt b/app/src/main/java/io/legado/app/ui/main/MainActivity.kt
index 4b1a01ef4..c63b53d05 100644
--- a/app/src/main/java/io/legado/app/ui/main/MainActivity.kt
+++ b/app/src/main/java/io/legado/app/ui/main/MainActivity.kt
@@ -22,7 +22,6 @@ import kotlinx.android.synthetic.main.activity_main.*
 
 class MainActivity : BaseActivity<MainViewModel>(), BottomNavigationView.OnNavigationItemSelectedListener,
     ViewPager.OnPageChangeListener {
-    private val mFragmentList: ArrayList<Fragment> = ArrayList()
 
     override val viewModel: MainViewModel
         get() = getViewModel(MainViewModel::class.java)
@@ -31,12 +30,8 @@ class MainActivity : BaseActivity<MainViewModel>(), BottomNavigationView.OnNavig
         get() = R.layout.activity_main
 
     override fun onViewModelCreated(viewModel: MainViewModel, savedInstanceState: Bundle?) {
-        mFragmentList.add(BookshelfFragment(R.layout.fragment_bookshelf))
-        mFragmentList.add(FindBookFragment(R.layout.fragment_find_book))
-        mFragmentList.add(BookSourceFragment(R.layout.fragment_book_source))
-        mFragmentList.add(MyConfigFragment(R.layout.fragment_my_config))
-        view_pager_main.adapter =
-            TabFragmentPageAdapter(supportFragmentManager, FragmentPagerAdapter.BEHAVIOR_RESUME_ONLY_CURRENT_FRAGMENT)
+        view_pager_main.offscreenPageLimit = 3
+        view_pager_main.adapter = TabFragmentPageAdapter(supportFragmentManager)
         view_pager_main.addOnPageChangeListener(this)
         bottom_navigation_view.setOnNavigationItemSelectedListener(this)
     }
@@ -81,17 +76,21 @@ class MainActivity : BaseActivity<MainViewModel>(), BottomNavigationView.OnNavig
         bottom_navigation_view.menu.getItem(position).isChecked = true
     }
 
-    inner class TabFragmentPageAdapter internal constructor(fm: FragmentManager, behavior: Int) :
-        FragmentPagerAdapter(fm, behavior) {
+    private inner class TabFragmentPageAdapter internal constructor(fm: FragmentManager) :
+        FragmentPagerAdapter(fm, BEHAVIOR_RESUME_ONLY_CURRENT_FRAGMENT) {
 
         override fun getItem(position: Int): Fragment {
-            return mFragmentList[position]
+            return when (position) {
+                0 -> BookshelfFragment()
+                1 -> FindBookFragment()
+                2 -> BookSourceFragment()
+                else -> MyConfigFragment()
+            }
         }
 
         override fun getCount(): Int {
-            return mFragmentList.size
+            return 4
         }
-
     }
 
 }
diff --git a/app/src/main/java/io/legado/app/ui/main/bookshelf/BookshelfFragment.kt b/app/src/main/java/io/legado/app/ui/main/bookshelf/BookshelfFragment.kt
index f47c26989..88c59221b 100644
--- a/app/src/main/java/io/legado/app/ui/main/bookshelf/BookshelfFragment.kt
+++ b/app/src/main/java/io/legado/app/ui/main/bookshelf/BookshelfFragment.kt
@@ -1,13 +1,17 @@
 package io.legado.app.ui.main.bookshelf
 
 import android.os.Bundle
+import android.util.Log
 import android.view.View
 import androidx.fragment.app.Fragment
+import io.legado.app.R
 
-class BookshelfFragment(contentLayoutId: Int) : Fragment(contentLayoutId) {
+class BookshelfFragment : Fragment(R.layout.fragment_bookshelf) {
 
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
         super.onViewCreated(view, savedInstanceState)
+        Log.e("TAG", "BookshelfFragment")
+
     }
 
 
diff --git a/app/src/main/java/io/legado/app/ui/main/booksource/BookSourceFragment.kt b/app/src/main/java/io/legado/app/ui/main/booksource/BookSourceFragment.kt
index c7700907b..7f0195ab9 100644
--- a/app/src/main/java/io/legado/app/ui/main/booksource/BookSourceFragment.kt
+++ b/app/src/main/java/io/legado/app/ui/main/booksource/BookSourceFragment.kt
@@ -1,13 +1,16 @@
 package io.legado.app.ui.main.booksource
 
 import android.os.Bundle
+import android.util.Log
 import android.view.View
 import androidx.fragment.app.Fragment
+import io.legado.app.R
 
-class BookSourceFragment(contentLayoutId: Int) : Fragment(contentLayoutId) {
+class BookSourceFragment : Fragment(R.layout.fragment_book_source) {
 
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
         super.onViewCreated(view, savedInstanceState)
+         Log.e("TAG", "BookSourceFragment")
     }
 
 }
\ No newline at end of file
diff --git a/app/src/main/java/io/legado/app/ui/main/findbook/FindBookFragment.kt b/app/src/main/java/io/legado/app/ui/main/findbook/FindBookFragment.kt
index 1f82bde48..ce2140978 100644
--- a/app/src/main/java/io/legado/app/ui/main/findbook/FindBookFragment.kt
+++ b/app/src/main/java/io/legado/app/ui/main/findbook/FindBookFragment.kt
@@ -1,13 +1,16 @@
 package io.legado.app.ui.main.findbook
 
 import android.os.Bundle
+import android.util.Log
 import android.view.View
 import androidx.fragment.app.Fragment
+import io.legado.app.R
 
-class FindBookFragment(contentLayoutId: Int) : Fragment(contentLayoutId) {
+class FindBookFragment : Fragment(R.layout.fragment_find_book) {
 
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
         super.onViewCreated(view, savedInstanceState)
+        Log.e("TAG", "FindBookFragment")
     }
 
 }
\ No newline at end of file
diff --git a/app/src/main/java/io/legado/app/ui/main/myconfig/MyConfigFragment.kt b/app/src/main/java/io/legado/app/ui/main/myconfig/MyConfigFragment.kt
index af07504b3..052f1324a 100644
--- a/app/src/main/java/io/legado/app/ui/main/myconfig/MyConfigFragment.kt
+++ b/app/src/main/java/io/legado/app/ui/main/myconfig/MyConfigFragment.kt
@@ -1,13 +1,16 @@
 package io.legado.app.ui.main.myconfig
 
 import android.os.Bundle
+import android.util.Log
 import android.view.View
 import androidx.fragment.app.Fragment
+import io.legado.app.R
 
-class MyConfigFragment(contentLayoutId: Int) : Fragment(contentLayoutId) {
+class MyConfigFragment : Fragment(R.layout.fragment_my_config) {
 
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
         super.onViewCreated(view, savedInstanceState)
+        Log.e("TAG", "MyConfigFragment")
     }
 
 }
\ No newline at end of file
diff --git a/app/src/main/java/io/legado/app/ui/widget/TitleBar.kt b/app/src/main/java/io/legado/app/ui/widget/TitleBar.kt
index 428500b6e..01597a940 100644
--- a/app/src/main/java/io/legado/app/ui/widget/TitleBar.kt
+++ b/app/src/main/java/io/legado/app/ui/widget/TitleBar.kt
@@ -14,6 +14,9 @@ import androidx.appcompat.widget.Toolbar
 import androidx.core.graphics.drawable.DrawableCompat
 import com.google.android.material.appbar.AppBarLayout
 import io.legado.app.R
+import io.legado.app.utils.getStatusBarHeight
+import org.jetbrains.anko.bottomPadding
+import org.jetbrains.anko.topPadding
 
 class TitleBar(context: Context, attrs: AttributeSet?) : AppBarLayout(context, attrs) {
 
@@ -84,6 +87,14 @@ class TitleBar(context: Context, attrs: AttributeSet?) : AppBarLayout(context, a
             }
         }
 
+        if (a.getBoolean(R.styleable.TitleBar_fitStatusBar, true)) {
+            topPadding = context.getStatusBarHeight()
+        }
+
+        if (a.getBoolean(R.styleable.TitleBar_fitNavigationBar, false)) {
+            bottomPadding = context.getStatusBarHeight()
+        }
+
         a.recycle()
 
         if (attachToActivity) {
@@ -122,8 +133,8 @@ class TitleBar(context: Context, attrs: AttributeSet?) : AppBarLayout(context, a
     private fun attachToActivity(context: Context) {
         val activity = getCompatActivity(context)
         activity?.let {
-            activity.setSupportActionBar(toolbar)
-            activity.supportActionBar?.setDisplayHomeAsUpEnabled(mDisplayHomeAsUp)
+            it.setSupportActionBar(toolbar)
+            it.supportActionBar?.setDisplayHomeAsUpEnabled(mDisplayHomeAsUp)
         }
     }
 
diff --git a/app/src/main/java/io/legado/app/utils/AnkoExtensions.kt b/app/src/main/java/io/legado/app/utils/AnkoExtensions.kt
index 4fdace873..591bd4ade 100644
--- a/app/src/main/java/io/legado/app/utils/AnkoExtensions.kt
+++ b/app/src/main/java/io/legado/app/utils/AnkoExtensions.kt
@@ -1,6 +1,12 @@
 package io.legado.app.utils
 
+import android.app.Activity
+import android.content.res.ColorStateList
+import android.graphics.drawable.Drawable
 import android.view.View
+import android.view.WindowManager
+import androidx.annotation.ColorRes
+import androidx.annotation.DrawableRes
 import androidx.annotation.StringRes
 import androidx.fragment.app.Fragment
 import com.google.android.material.snackbar.Snackbar
@@ -51,3 +57,9 @@ fun Fragment.longToast(text: CharSequence) = requireActivity().longToast(text)
 fun Fragment.dip(value: Int): Int = requireActivity().dip(value)
 
 fun Fragment.dip(value: Float): Int = requireActivity().dip(value)
+
+fun Fragment.getCompatColor(@ColorRes id: Int): Int = requireContext().getCompatColor(id)
+
+fun Fragment.getCompatDrawable(@DrawableRes id: Int): Drawable? = requireContext().getCompatDrawable(id)
+
+fun Fragment.getCompatColorStateList(@ColorRes id: Int): ColorStateList? = requireContext().getCompatColorStateList(id)
\ No newline at end of file
diff --git a/app/src/main/java/io/legado/app/utils/ContextExtensions.kt b/app/src/main/java/io/legado/app/utils/ContextExtensions.kt
index a94267fda..6a80cd841 100644
--- a/app/src/main/java/io/legado/app/utils/ContextExtensions.kt
+++ b/app/src/main/java/io/legado/app/utils/ContextExtensions.kt
@@ -1,6 +1,11 @@
 package io.legado.app.utils
 
 import android.content.Context
+import android.content.res.ColorStateList
+import android.graphics.drawable.Drawable
+import androidx.annotation.ColorRes
+import androidx.annotation.DrawableRes
+import androidx.core.content.ContextCompat
 import androidx.core.content.edit
 import org.jetbrains.anko.connectivityManager
 import org.jetbrains.anko.defaultSharedPreferences
@@ -40,3 +45,15 @@ fun Context.putPrefStringSet(key: String, value: MutableSet<String>) =
 
 fun Context.removePref(key: String) =
     defaultSharedPreferences.edit { remove(key) }
+
+
+fun Context.getCompatColor(@ColorRes id: Int): Int = ContextCompat.getColor(this, id)
+
+fun Context.getCompatDrawable(@DrawableRes id: Int): Drawable? = ContextCompat.getDrawable(this, id)
+
+fun Context.getCompatColorStateList(@ColorRes id: Int): ColorStateList? = ContextCompat.getColorStateList(this, id)
+
+fun Context.getStatusBarHeight(): Int {
+    val resourceId = resources.getIdentifier("status_bar_height", "dimen", "android")
+    return resources.getDimensionPixelSize(resourceId)
+}
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
index a0730b697..411c77428 100644
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -3,13 +3,13 @@
         xmlns:android="http://schemas.android.com/apk/res/android"
         xmlns:app="http://schemas.android.com/apk/res-auto"
         android:layout_width="match_parent"
-        android:layout_height="match_parent"
-        android:fitsSystemWindows="true">
+        android:layout_height="match_parent">
 
     <com.google.android.material.bottomnavigation.BottomNavigationView
             android:id="@+id/bottom_navigation_view"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
+            android:elevation="6dp"
             android:background="@color/background"
             app:labelVisibilityMode="labeled"
             app:menu="@menu/activity_main_bnv"
diff --git a/app/src/main/res/layout/fragment_book_source.xml b/app/src/main/res/layout/fragment_book_source.xml
index a845edf1a..ae3d1f23c 100644
--- a/app/src/main/res/layout/fragment_book_source.xml
+++ b/app/src/main/res/layout/fragment_book_source.xml
@@ -9,6 +9,7 @@
             android:id="@+id/title_bar"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
+            app:attachToActivity="false"
             app:layout_constraintTop_toTopOf="parent"
             app:title="@string/book_source"/>
 
diff --git a/app/src/main/res/layout/fragment_bookshelf.xml b/app/src/main/res/layout/fragment_bookshelf.xml
index 2360d6d70..4469491be 100644
--- a/app/src/main/res/layout/fragment_bookshelf.xml
+++ b/app/src/main/res/layout/fragment_bookshelf.xml
@@ -1,15 +1,17 @@
 <?xml version="1.0" encoding="utf-8"?>
-<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
-              xmlns:app="http://schemas.android.com/apk/res-auto"
-              android:orientation="vertical"
-              android:layout_width="match_parent"
-              android:layout_height="match_parent">
+<androidx.constraintlayout.widget.ConstraintLayout
+        xmlns:android="http://schemas.android.com/apk/res/android"
+        xmlns:app="http://schemas.android.com/apk/res-auto"
+        android:orientation="vertical"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent">
 
     <io.legado.app.ui.widget.TitleBar
             android:id="@+id/title_bar"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
+            app:attachToActivity="false"
             app:layout_constraintTop_toTopOf="parent"
             app:title="@string/bookshelf"/>
 
-</LinearLayout>
\ No newline at end of file
+</androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/fragment_find_book.xml b/app/src/main/res/layout/fragment_find_book.xml
index 4c8e1609e..c7eeea4da 100644
--- a/app/src/main/res/layout/fragment_find_book.xml
+++ b/app/src/main/res/layout/fragment_find_book.xml
@@ -9,6 +9,7 @@
             android:id="@+id/title_bar"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
+            app:attachToActivity="false"
             app:layout_constraintTop_toTopOf="parent"
             app:title="@string/find"/>
 
diff --git a/app/src/main/res/layout/fragment_my_config.xml b/app/src/main/res/layout/fragment_my_config.xml
index a4b260fa9..9fe7b70f7 100644
--- a/app/src/main/res/layout/fragment_my_config.xml
+++ b/app/src/main/res/layout/fragment_my_config.xml
@@ -1,7 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
-<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
               xmlns:app="http://schemas.android.com/apk/res-auto"
-              android:orientation="vertical"
               android:layout_width="match_parent"
               android:layout_height="match_parent">
 
@@ -9,7 +8,9 @@
             android:id="@+id/title_bar"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
+            app:attachToActivity="false"
             app:layout_constraintTop_toTopOf="parent"
             app:title="我的"/>
 
-</LinearLayout>
\ No newline at end of file
+
+</androidx.constraintlayout.widget.ConstraintLayout>
\ No newline at end of file
diff --git a/app/src/main/res/values/attrs.xml b/app/src/main/res/values/attrs.xml
index b60fcb652..75b4d171f 100644
--- a/app/src/main/res/values/attrs.xml
+++ b/app/src/main/res/values/attrs.xml
@@ -11,6 +11,8 @@
         <attr name="attachToActivity" format="boolean"/>
         <attr name="displayHomeAsUp" format="boolean"/>
         <attr name="navigationIcon" format="reference"/>
+        <attr name="fitStatusBar" format="boolean"/>
+        <attr name="fitNavigationBar" format="boolean"/>
         <attr name="navigationContentDescription" format="reference|string"/>
         <attr name="navigationIconTint" format="color|reference"/>
         <attr name="navigationIconTintMode" format="enum">
diff --git a/app/src/main/res/values/styles.xml b/app/src/main/res/values/styles.xml
index 15c10c068..8dbf324cb 100644
--- a/app/src/main/res/values/styles.xml
+++ b/app/src/main/res/values/styles.xml
@@ -31,7 +31,8 @@
         <item name="actionOverflowMenuStyle">@style/Style.PopupMenu</item>
         <item name="android:itemTextAppearance">@style/Style.MenuItemText</item>
         <item name="android:popupMenuStyle">@style/Style.PopupMenu</item>
-        <item name="android:windowTranslucentStatus">true</item>
+        <item name="android:statusBarColor">@color/transparent</item>
+        <item name="android:windowDrawsSystemBarBackgrounds">true</item>
     </style>
 
     <style name="AppTheme.AppBarOverlay.Light" parent="ThemeOverlay.AppCompat.Light">
diff --git a/gradle.properties b/gradle.properties
index 23339e0df..376270d77 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -18,4 +18,4 @@ android.useAndroidX=true
 # Automatically convert third-party libraries to use AndroidX
 android.enableJetifier=true
 # Kotlin code style for this project: "official" or "obsolete":
-kotlin.code.style=official
+kotlin.code.style=official
\ No newline at end of file