Android 在何处添加工具栏和导航栏

我使用的是android导航控制器

我的主活动承载一个导航片段，但其他组件（如工具栏和导航底部栏）应该放在主活动还是子片段中

activity_main.xml

<?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:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

     <androidx.appcompat.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        app:layout_collapseMode="pin"
        app:popupTheme="@style/AppTheme.PopupOverlay" />

    <fragment
        android:id="@+id/nav_host_fragment"
        android:name="androidx.navigation.fragment.NavHostFragment"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        app:defaultNavHost="true"
        app:navGraph="@navigation/navigation" />

    <android.support.design.widget.BottomNavigationView
        android:id="@+id/bottom_nav_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:menu="@menu/menu_bottom_nav" />

</LinearLayout>

fragment_home.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

        <androidx.recyclerview.widget.RecyclerView
            android:id="@+id/recyclerList"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:scrollbars="vertical" />
</RelativeLayout>

或者ToolBar和BottomNavigationView应该像这样位于fragment_home.xml中吗

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

     <androidx.appcompat.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        app:layout_collapseMode="pin"
        app:popupTheme="@style/AppTheme.PopupOverlay" />

        <androidx.recyclerview.widget.RecyclerView
            android:id="@+id/recyclerList"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:scrollbars="vertical" />

    <android.support.design.widget.BottomNavigationView
        android:id="@+id/bottom_nav_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:menu="@menu/menu_bottom_nav" />
</RelativeLayout>

---

我给你举个例子。请记住，我正在使用最新的androidx for SDK 28+进行编译，因此如果您使用的是较旧的，那么您的名称空间将略有不同

我也在使用数据绑定和Kotlin，所以如果不使用数据绑定，就不要使用布局和数据标记

工具栏

<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools">

<data>
     PUT BINDING VARIABLES HERE
</data>

<androidx.coordinatorlayout.widget.CoordinatorLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.google.android.material.appbar.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/SSTheme.AppBarOverlay">

        <androidx.appcompat.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?android:attr/actionBarSize"
            android:theme="@style/ToolbarTextAppearance">

        </androidx.appcompat.widget.Toolbar>

    </com.google.android.material.appbar.AppBarLayout>

</androidx.coordinatorlayout.widget.CoordinatorLayout>

你没有问这个，但我也会提供。当您需要更改片段时，我通常有一个BaseActivity和一个helper方法，它就是这样做的

 protected fun swapFragment(fragment: BaseFragment, @Nullable bundle: Bundle?, hideCurrentFrag: Boolean = false) {
    if (fragment.isVisible) {
        A35Log.e(mClassTag, "swapFragment called on already visible fragment")
        return
    }

    A35Log.v(mClassTag, "swapFragment( ${fragment.javaClass.simpleName} )")
    val currentFragBundle = fragment.arguments
    if (currentFragBundle == null && bundle != null) {
        fragment.arguments = bundle
        A35Log.v(mClassTag, "current bundle is null, so setting new bundle passed in")
    } else if (bundle != null) {
        fragment.arguments?.putAll(bundle)
        A35Log.v(mClassTag, "current fragment bundle was not null, so add new bundle to it")
    }

    val fragmentManager = supportFragmentManager
    fragmentManager.executePendingTransactions()
    val fragmentTransaction = fragmentManager.beginTransaction()

    //Make sure the requested fragment isn't already on the screen before adding it
    if (fragment.isAdded) {
        A35Log.v(mClassTag, "Fragment is already added")
        if (fragment.isHidden) {
            A35Log.v(mClassTag, "Fragment is hidden, so show it")
            fragmentTransaction.show(fragment)
            if(hideCurrentFrag) {
                A35Log.v(mClassTag, "hideCurrentFlag = true, hiding current fragment $mSelectedFragment")
                fragmentTransaction.hide(mSelectedFragment!!)
            }else{
                A35Log.v(mClassTag, "hideCurrentFlag = false, removing current fragment $mSelectedFragment")
                fragmentTransaction.remove(mSelectedFragment!!)
            }
        }else{
            A35Log.v(mClassTag, "Fragment is already visible")
        }
    }else if(mSelectedFragment == null){
        A35Log.v(mClassTag,"mSelectedFragment = null, so replacing active fragment with new one ${fragment.javaClass.simpleName}")
        fragmentTransaction.replace(R.id.fragPlaceholder, fragment)
    }else{
        A35Log.v(mClassTag, "Fragment is not added, so adding to the screen ${fragment.javaClass.simpleName}")
        fragmentTransaction.add(R.id.fragPlaceholder, fragment)
        if(hideCurrentFrag) {
            A35Log.v(mClassTag, "hideCurrentFlag = true, hiding current fragment $mSelectedFragment")
            fragmentTransaction.hide(mSelectedFragment!!)
        }else{
            A35Log.v(mClassTag, "hideCurrentFlag = false, removing current fragment $mSelectedFragment")
            fragmentTransaction.remove(mSelectedFragment!!)
        }
    }

    A35Log.v(mClassTag, "committing swap fragment transaction")
    fragmentTransaction.commit()
    A35Log.v(mClassTag, "mSelectedFragment = ${fragment.javaClass.simpleName}")
    mSelectedFragment = fragment
}

注意*虽然交换片段是相当普遍的，但您需要确保正确处理您的需求。它应该隐藏，还是移除。它应该处理捆绑包还是忽略它们。我提供给您的方法基本上是显示if不存在并隐藏片段，而不是删除if来隐藏它

这里没有显示为导航抽屉构建适配器和列表以及连接侦听器单击这些项目的操作，因为这不是您的问题，超出了本问题的范围。我不想让我的答案过于浮夸，所以希望这就是你所需要的一切

快乐编码

   <!--Full Screen-->
<style name="A35.FullScreen">
    <item name="windowActionBar">false</item>
    <item name="windowNoTitle">true</item>
    <item name="android:windowFullscreen">true</item>
</style>

  <application
    android:name=".application.A35Application"
    android:allowBackup="true"
    android:icon="@mipmap/a35_logo"
    android:label="@string/app_name"
    android:supportsRtl="true"
    android:theme="@style/A35.FullScreen">

setSupportActionBar(toolbar)

 protected fun swapFragment(fragment: BaseFragment, @Nullable bundle: Bundle?, hideCurrentFrag: Boolean = false) {
    if (fragment.isVisible) {
        A35Log.e(mClassTag, "swapFragment called on already visible fragment")
        return
    }

    A35Log.v(mClassTag, "swapFragment( ${fragment.javaClass.simpleName} )")
    val currentFragBundle = fragment.arguments
    if (currentFragBundle == null && bundle != null) {
        fragment.arguments = bundle
        A35Log.v(mClassTag, "current bundle is null, so setting new bundle passed in")
    } else if (bundle != null) {
        fragment.arguments?.putAll(bundle)
        A35Log.v(mClassTag, "current fragment bundle was not null, so add new bundle to it")
    }

    val fragmentManager = supportFragmentManager
    fragmentManager.executePendingTransactions()
    val fragmentTransaction = fragmentManager.beginTransaction()

    //Make sure the requested fragment isn't already on the screen before adding it
    if (fragment.isAdded) {
        A35Log.v(mClassTag, "Fragment is already added")
        if (fragment.isHidden) {
            A35Log.v(mClassTag, "Fragment is hidden, so show it")
            fragmentTransaction.show(fragment)
            if(hideCurrentFrag) {
                A35Log.v(mClassTag, "hideCurrentFlag = true, hiding current fragment $mSelectedFragment")
                fragmentTransaction.hide(mSelectedFragment!!)
            }else{
                A35Log.v(mClassTag, "hideCurrentFlag = false, removing current fragment $mSelectedFragment")
                fragmentTransaction.remove(mSelectedFragment!!)
            }
        }else{
            A35Log.v(mClassTag, "Fragment is already visible")
        }
    }else if(mSelectedFragment == null){
        A35Log.v(mClassTag,"mSelectedFragment = null, so replacing active fragment with new one ${fragment.javaClass.simpleName}")
        fragmentTransaction.replace(R.id.fragPlaceholder, fragment)
    }else{
        A35Log.v(mClassTag, "Fragment is not added, so adding to the screen ${fragment.javaClass.simpleName}")
        fragmentTransaction.add(R.id.fragPlaceholder, fragment)
        if(hideCurrentFrag) {
            A35Log.v(mClassTag, "hideCurrentFlag = true, hiding current fragment $mSelectedFragment")
            fragmentTransaction.hide(mSelectedFragment!!)
        }else{
            A35Log.v(mClassTag, "hideCurrentFlag = false, removing current fragment $mSelectedFragment")
            fragmentTransaction.remove(mSelectedFragment!!)
        }
    }

    A35Log.v(mClassTag, "committing swap fragment transaction")
    fragmentTransaction.commit()
    A35Log.v(mClassTag, "mSelectedFragment = ${fragment.javaClass.simpleName}")
    mSelectedFragment = fragment
}