我正在将活动解析为片段，因此我想使用 JetPack 中的导航组件，因此我创建了图形、片段并将我的布局复制并粘贴到片段布局并创建导航，但现在我尝试对已在工作的相同布局进行膨胀时出错。
我测试了其他片段并且它起作用了，所以它不是活动，我只是让片段布局膨胀并得到相同的错误。是什么让我想到，通过消除，这可能是片段布局的问题。
import android.os.Bundle
import android.view.MenuItem
import androidx.appcompat.app.AppCompatActivity
import androidx.fragment.app.Fragment
import com.google.android.material.bottomnavigation.BottomNavigationView
import com.quicktendr.mgmt.androidApp.R
import com.quicktendr.mgmt.androidApp.databinding.ActivityManagementBinding
import com.quicktendr.mgmt.androidApp.ui.screen.OrdersFragment
class ManagementActivity : AppCompatActivity(),
BottomNavigationView.OnNavigationItemSelectedListener {
private lateinit var binding: ActivityManagementBinding
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = ActivityManagementBinding.inflate(layoutInflater)
setContentView(binding.root)
startFragment()
}
private fun startFragment() {
setFragmentOnHost(OrdersFragment())
}
private fun setFragmentOnHost(fragment: Fragment) {
supportFragmentManager.beginTransaction()
.add(R.id.nav_host_fragment, fragment)
.commit()
}
override fun onResume() {
super.onResume()
binding.bottomNav.setOnNavigationItemSelectedListener(this)
}
override fun onNavigationItemSelected(item: MenuItem): Boolean {
when(item.itemId) {
R.id.menu_order -> setFragmentOnHost(OrdersFragment())
}
return true
}
}
片段：
class OrdersFragment : Fragment() {
private val viewModel: RestaurantViewModel by lazy {
ViewModelProvider(this).get(
RestaurantViewModel::class.java
)
}
private lateinit var binding: FragmentOrdersBinding
private var paused: Boolean = true
private val activityContext = requireActivity()
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View {
binding = FragmentOrdersBinding.inflate(layoutInflater, container, false)
return binding.root
}
}
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.quicktendr.mgmt.androidApp, PID: 28706
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.quicktendr.mgmt.androidApp/com.quicktendr.mgmt.androidApp.ui.ManagementActivity}: android.view.InflateException: Binary XML file line #20: Binary XML file line #20: Error inflating class fragment
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2778)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6494)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:439)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
Caused by: android.view.InflateException: Binary XML file line #20: Binary XML file line #20: Error inflating class fragment
Caused by: android.view.InflateException: Binary XML file line #20: Error inflating class fragment
Caused by: androidx.fragment.app.Fragment$InstantiationException: Unable to instantiate fragment com.quicktendr.mgmt.androidApp.ui.screen.OrdersFragment: calling Fragment constructor caused an exception
at androidx.fragment.app.Fragment.instantiate(Fragment.java:628)
at androidx.fragment.app.FragmentContainer.instantiate(FragmentContainer.java:57)
at androidx.fragment.app.FragmentManager$3.instantiate(FragmentManager.java:483)
at androidx.navigation.fragment.FragmentNavigator.instantiateFragment(FragmentNavigator.java:132)
at androidx.navigation.fragment.FragmentNavigator.navigate(FragmentNavigator.java:162)
at androidx.navigation.fragment.FragmentNavigator.navigate(FragmentNavigator.java:58)
at androidx.navigation.NavGraphNavigator.navigate(NavGraphNavigator.java:71)
at androidx.navigation.NavGraphNavigator.navigate(NavGraphNavigator.java:28)
at androidx.navigation.NavController.navigate(NavController.java:1059)
at androidx.navigation.NavController.onGraphCreated(NavController.java:639)
at androidx.navigation.NavController.setGraph(NavController.java:592)
at androidx.navigation.NavController.setGraph(NavController.java:557)
at androidx.navigation.NavController.setGraph(NavController.java:539)
at androidx.navigation.fragment.NavHostFragment.onCreate(NavHostFragment.java:248)
at androidx.fragment.app.Fragment.performCreate(Fragment.java:2936)
at androidx.fragment.app.FragmentStateManager.create(FragmentStateManager.java:472)
at androidx.fragment.app.FragmentStateManager.moveToExpectedState(FragmentStateManager.java:278)
at androidx.fragment.app.FragmentLayoutInflaterFactory.onCreateView(FragmentLayoutInflaterFactory.java:141)
at androidx.fragment.app.FragmentController.onCreateView(FragmentController.java:135)
at androidx.fragment.app.FragmentActivity.dispatchFragmentsOnCreateView(FragmentActivity.java:313)
at androidx.fragment.app.FragmentActivity.onCreateView(FragmentActivity.java:292)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:780)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:730)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:863)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
at com.quicktendr.mgmt.androidApp.databinding.ActivityManagementBinding.inflate(ActivityManagementBinding.java:44)
at com.quicktendr.mgmt.androidApp.databinding.ActivityManagementBinding.inflate(ActivityManagementBinding.java:38)
at com.quicktendr.mgmt.androidApp.ui.ManagementActivity.onCreate(ManagementActivity.kt:20)
at android.app.Activity.performCreate(Activity.java:6999)
at android.app.Activity.performCreate(Activity.java:6990)
E/AndroidRuntime: at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1214)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2731)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6494)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:439)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Constructor.newInstance0(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:334)
at androidx.fragment.app.Fragment.instantiate(Fragment.java:610)
... 42 more
Caused by: java.lang.IllegalStateException: Fragment OrdersFragment{88e14c1} (b9e50338-6a7b-49ea-9d09-0cd62aec3759)} not attached to an activity.
at androidx.fragment.app.Fragment.requireActivity(Fragment.java:926)
at com.quicktendr.mgmt.androidApp.ui.screen.OrdersFragment.<init>(OrdersFragment.kt:49)
... 45 more
最后是可能的问题，片段布局
<?xml version="1.0" encoding="utf-8"?>
<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="match_parent"
tools:context=".ui.screen.OrdersFragment">
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent">
<androidx.constraintlayout.widget.ConstraintLayout
android:id="@+id/cl_restaurant_header"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#c20000"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<androidx.appcompat.widget.LinearLayoutCompat
android:layout_width="500dp"
android:layout_height="wrap_content"
android:layout_margin="12dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<com.google.android.material.textfield.TextInputLayout
android:id="@+id/til_restaurant_list"
style="@style/Widget.MaterialComponents.TextInputLayout.FilledBox.ExposedDropdownMenu"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="8dp"
android:backgroundTint="@android:color/transparent"
app:boxStrokeColor="@android:color/transparent"
app:endIconTint="@android:color/white">
<AutoCompleteTextView
android:id="@+id/actv_restaurant_list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:backgroundTint="@android:color/transparent"
android:inputType="none"
android:textColor="@android:color/white"
android:textSize="24sp" />
</com.google.android.material.textfield.TextInputLayout>
</androidx.appcompat.widget.LinearLayoutCompat>
</androidx.constraintlayout.widget.ConstraintLayout>
<androidx.constraintlayout.widget.ConstraintLayout
android:id="@+id/cl_order_restaurant_actions"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@id/cl_restaurant_header"
app:layout_constraintBottom_toTopOf="@id/view_list_label">
<com.google.android.material.textfield.TextInputLayout
android:id="@+id/til_search_order"
android:layout_width="300dp"
android:layout_height="wrap_content"
app:startIconDrawable="@drawable/ic_baseline_search_24"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
>
<com.google.android.material.textfield.TextInputEditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@android:color/transparent"/>
</com.google.android.material.textfield.TextInputLayout>
<androidx.constraintlayout.widget.ConstraintLayout
android:id="@+id/cl_add_subtract_time"
android:layout_width="wrap_content"
android:layout_height="42dp"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
>
<ImageButton
android:id="@+id/btn_subtract_time"
android:layout_width="42dp"
android:layout_height="42dp"
android:background="@drawable/round_button_shape"
android:src="@drawable/ic_subtract"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="@id/tv_minutes"
/>
<TextView
android:id="@+id/tv_minutes"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:textSize="22sp"
android:textStyle="bold"
android:textColor="@android:color/black"
android:gravity="center"
android:layout_marginHorizontal="8dp"
tools:text="45'"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintStart_toEndOf="@id/btn_subtract_time"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="@+id/btn_add_time"
/>
<ImageButton
android:id="@+id/btn_add_time"
android:layout_width="42dp"
android:layout_height="42dp"
android:background="@drawable/round_button_shape"
android:src="@drawable/ic_baseline_add_24"
app:layout_constraintStart_toEndOf="@+id/tv_minutes"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
/>
</androidx.constraintlayout.widget.ConstraintLayout>
<ImageButton
android:id="@+id/btn_play_pause"
android:layout_width="42dp"
android:layout_height="42dp"
android:layout_marginEnd="36dp"
android:src="@drawable/ic_baseline_play_arrow_24"
android:background="@drawable/round_button"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
/>
</androidx.constraintlayout.widget.ConstraintLayout>
<View
android:id="@+id/view_list_label"
android:layout_width="match_parent"
android:layout_height="50dp"
android:background="#F4D8D7"
app:layout_constraintBottom_toTopOf="@+id/cl_order_restaurant_actions"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@id/cl_order_restaurant_actions" />
<TextView
android:id="@+id/tv_label_order_num"
style="@style/OrderTextLabel"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="@id/view_list_label"
app:layout_constraintEnd_toStartOf="@+id/gl_order_num_to_type"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="@+id/view_list_label" />
<TextView
android:id="@+id/tv_label_type"
style="@style/OrderTextLabel"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="@id/view_list_label"
app:layout_constraintEnd_toStartOf="@+id/gl_type_to_user"
app:layout_constraintStart_toEndOf="@+id/gl_order_num_to_type"
app:layout_constraintTop_toTopOf="@+id/view_list_label" />
<TextView
android:id="@+id/tv_label_user"
style="@style/OrderTextLabel"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="@id/view_list_label"
app:layout_constraintEnd_toStartOf="@+id/gl_user_to_state"
app:layout_constraintStart_toEndOf="@+id/gl_type_to_user"
app:layout_constraintTop_toTopOf="@+id/view_list_label" />
<TextView
android:id="@+id/tv_label_state"
style="@style/OrderTextLabel"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="@id/view_list_label"
app:layout_constraintEnd_toStartOf="@+id/gl_state_to_value"
app:layout_constraintStart_toEndOf="@+id/gl_user_to_state"
app:layout_constraintTop_toTopOf="@+id/view_list_label" />
<TextView
android:id="@+id/tv_label_value"
style="@style/OrderTextLabel"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="@id/view_list_label"
app:layout_constraintEnd_toStartOf="@+id/gl_value_to_delivery_hour"
app:layout_constraintStart_toEndOf="@+id/gl_state_to_value"
app:layout_constraintTop_toTopOf="@+id/view_list_label" />
<TextView
android:id="@+id/tv_label_delivery_hour"
style="@style/OrderTextLabel"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="@id/view_list_label"
app:layout_constraintEnd_toStartOf="@+id/gl_delivery_hour_to_action"
app:layout_constraintStart_toEndOf="@+id/gl_value_to_delivery_hour"
app:layout_constraintTop_toTopOf="@+id/view_list_label" />
<TextView
android:id="@+id/tv_label_action"
style="@style/OrderTextLabel"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="@id/view_list_label"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="@+id/gl_delivery_hour_to_action"
app:layout_constraintTop_toTopOf="@+id/view_list_label" />
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/rv_order_list"
android:layout_width="match_parent"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="@id/view_list_label" />
<androidx.constraintlayout.widget.Guideline
android:id="@+id/gl_order_num_to_type"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_percent="0.125" />
<androidx.constraintlayout.widget.Guideline
android:id="@+id/gl_type_to_user"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_percent="0.22" />
<androidx.constraintlayout.widget.Guideline
android:id="@+id/gl_user_to_state"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_percent="0.45" />
<androidx.constraintlayout.widget.Guideline
android:id="@+id/gl_state_to_value"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_percent="0.59" />
<androidx.constraintlayout.widget.Guideline
android:id="@+id/gl_value_to_delivery_hour"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_percent="0.68" />
<androidx.constraintlayout.widget.Guideline
android:id="@+id/gl_delivery_hour_to_action"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_percent="0.8" />
</androidx.constraintlayout.widget.ConstraintLayout>
</FrameLayout>
同样的布局在之前的活动中使用过。
答案 0 :(得分：2)
删除
private val activityContext = requireActivity()
在您的 OrdersFragment 中。该片段在初始化阶段尚未附加到任何活动，从而导致异常，并且存储对字段的活动引用是多余的，无论如何都容易发生内存泄漏。