從片段中打開活動的抽屜

Question

我想將片段中的 MaterialToolbar 設置為 Activity 的 supportActionBar 以打開抽屜（與 Hamburger 圖標一樣）。

這是我的HomeActivity xml：

<androidx.drawerlayout.widget.DrawerLayout 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"
    android:id="@+id/drawer"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".ui.home.HomeActivity">

    <androidx.constraintlayout.widget.ConstraintLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <androidx.fragment.app.FragmentContainerView
            android:id="@+id/search_fragment"
            android:name=".ui.home.search.SearchFragment"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:layout_constraintBottom_toTopOf="@+id/fragmentHomeContainerView"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent"
            tools:layout="@layout/fragment_search" />

        <androidx.fragment.app.FragmentContainerView
            android:id="@+id/fragmentHomeContainerView"
            android:name="androidx.navigation.fragment.NavHostFragment"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            app:defaultNavHost="true"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintHorizontal_bias="0.0"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/search_fragment"
            app:navGraph="@navigation/nav_home" />

    </androidx.constraintlayout.widget.ConstraintLayout>

    <com.google.android.material.navigation.NavigationView
        android:id="@+id/navigation_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:clipToPadding="false"
        android:visibility="visible"
        app:headerLayout="@layout/nav_header"
        app:menu="@menu/main_menu" />


</androidx.drawerlayout.widget.DrawerLayout>

SearchFragment xml 包含 MaterialToolbar，如下所示：

<FrameLayout 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"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    tools:context=".ui.home.search.SearchFragment">

    <com.google.android.material.appbar.AppBarLayout
        android:id="@+id/appBarLayout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginHorizontal="24dp"
        android:layout_marginStart="16dp"
        android:layout_marginTop="8dp"
        android:layout_marginEnd="16dp"
        android:background="@android:color/transparent"
        android:elevation="0dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_scrollFlags="scroll|enterAlways|snap"
        app:liftOnScroll="true">

        <com.google.android.material.appbar.MaterialToolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="60dp"
            android:layout_gravity="center"
            android:layout_margin="6dp"
            android:background="@drawable/rounded_toolbar"
            android:elevation="6dp"
            android:minHeight="?attr/actionBarSize"
            app:contentInsetStart="0dp"
            app:contentInsetStartWithNavigation="0dp"
            app:navigationIcon="@drawable/ic_baseline_menu_24"
            app:titleTextColor="@android:color/white">

            <EditText
                android:id="@+id/entities_search"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:autofillHints="Search for client"
                android:background="@android:color/transparent"
                android:hint="@string/search_toolbar"
                android:inputType="textPersonName"
                android:minHeight="48dp"
                android:textColorHint="@color/search_toolbar" />
        </com.google.android.material.appbar.MaterialToolbar>
    </com.google.android.material.appbar.AppBarLayout>
</FrameLayout>

這是 HomeActivity.kt 中抽屜和setSupportActionBar的HomeActivity.kt ：

class HomeActivity : AppCompatActivity() {

    private val homeModel: HomeViewModel by viewModels()
    private lateinit var drawerToggle: ActionBarDrawerToggle
    val binding: ActivityHomeBinding by lazy {
        ActivityHomeBinding.inflate(layoutInflater)
    }
    val entityModel: EntityViewModel by viewModels()

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        println("Home Activity onCreate")
        setContentView(binding.root)
        initDrawer()
    }

    private fun initDrawer() {
        val toolbar = binding.searchFragment.findViewById<MaterialToolbar>(R.id.toolbar)
        setSupportActionBar(toolbar)
        drawerToggle = ActionBarDrawerToggle(
            this,
            binding.drawer,
            toolbar,
            R.string.open_drawer,
            R.string.close_drawer
        )
        binding.drawer.addDrawerListener(drawerToggle)
        drawerToggle.syncState()
        supportActionBar?.setDisplayHomeAsUpEnabled(true)

        binding.navigationView.setNavigationItemSelectedListener {
            handleNavigationItemSelected(it)
            true
        }
    }

    private fun handleNavigationItemSelected(item: MenuItem) {
        println("selecting menu item")
        when (item.itemId) {
            R.id.nav_account -> {
                selectAccount()
                if (binding.drawer.isDrawerOpen(GravityCompat.START)) {
                    binding.drawer.closeDrawer(GravityCompat.START)
                }
            }
        }
    }

    override fun onOptionsItemSelected(item: MenuItem): Boolean {
        return if (drawerToggle.onOptionsItemSelected(item)) {
            true
        } else {
            super.onOptionsItemSelected(item)
        }
    }

    override fun onBackPressed() {
        super.onBackPressed()
        println("Home Activity onBackPressed")
        if (binding.drawer.isDrawerOpen(GravityCompat.START)) {
            binding.drawer.closeDrawer(GravityCompat.START)
        } else {
            super.onBackPressed()
        }
    }

    override fun onDestroy() {}
}

因此，如果我確實有來自ActivityHome xml 內的SearchFragment的 xml 代碼（不是片段），當工具欄位於 xml 抽屜內時，上述代碼有效。 但是，當工具欄被帶到片段上時，它不起作用，即使片段在抽屜內，也不會出現漢堡包圖標。

SearchFragment.kt沒什么大不了的：

class SearchFragment : Fragment() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
    }

    private val binding: FragmentSearchBinding by lazy {
        FragmentSearchBinding.bind(requireView())
    }
    private val model: EntityViewModel by lazy {
        (requireActivity() as HomeActivity).entityModel
    }

    override fun onCreateView(
        inflater: LayoutInflater,
        container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        return inflater.inflate(R.layout.fragment_search, container, false)
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        initSearch()
    }

    private fun initSearch() {
        binding.entitiesSearch.addTextChangedListener {
            model.search(it.toString())
        }
    }
}

如何實現在 fragment 中打開帶有 Hamburguer 圖標的抽屜？

Answer 1

制作一個名為openDrawer()的 function 並初始化此 function 以在調用時打開抽屜，