Question

我想在导航抽屉中添加一个旋转的顶部，我希望它看起来像这样：

我找不到添加方式和位置。尝试查找ID时总是会收到此错误

我的微调器布局

<Spinner
    xmlns:android="http://schemas.android.com/apk/res/android"

            android:id="@+id/qualitySpinner"
            android:layout_marginLeft="50dp"
            android:entries="@array/mQuality"
            android:layout_width="match_parent"
            android:layout_height="match_parent"/>

和我的物品

<item
        android:id="@+id/right_menu_spinner"
        android:icon="@drawable/icon_default"
        android:title="Quality"
        app:actionLayout="@layout/spinner_layout"/>

和我的片段代码

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

        val array = arrayOf("deneme","deneme")
        val denemeSp : Spinner = view.findViewById(R.id.qualitySpinner)
        denemeSp.adapter = ArrayAdapter(view.context,android.R.layout.simple_spinner_item,array)
        denemeSp.setOnItemSelectedListener(this)
}

但是在工作时会出现以下错误：

2020-06-07 23:12:41.292 6872-6872/com.enesseval.moviedeneme E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.enesseval.moviedeneme, PID: 6872
    java.lang.IllegalStateException: view.findViewById(R.id.qualitySpinner) must not be null
        at com.enesseval.moviedeneme.view.MoviesFragment.onViewCreated(MoviesFragment.kt:57)
        at androidx.fragment.app.FragmentStateManager.createView(FragmentStateManager.java:332)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1187)
        at androidx.fragment.app.FragmentManager.addAddedFragments(FragmentManager.java:2224)
        at androidx.fragment.app.FragmentManager.executeOpsTogether(FragmentManager.java:1997)
        at androidx.fragment.app.FragmentManager.removeRedundantOperationsAndExecute(FragmentManager.java:1953)
        at androidx.fragment.app.FragmentManager.execPendingActions(FragmentManager.java:1849)
        at androidx.fragment.app.FragmentManager.dispatchStateChange(FragmentManager.java:2629)
        at androidx.fragment.app.FragmentManager.dispatchActivityCreated(FragmentManager.java:2577)
        at androidx.fragment.app.Fragment.performActivityCreated(Fragment.java:2722)
        at androidx.fragment.app.FragmentStateManager.activityCreated(FragmentStateManager.java:346)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1188)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1356)
        at androidx.fragment.app.FragmentManager.moveFragmentToExpectedState(FragmentManager.java:1434)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1497)
        at androidx.fragment.app.FragmentManager.dispatchStateChange(FragmentManager.java:2625)
        at androidx.fragment.app.FragmentManager.dispatchActivityCreated(FragmentManager.java:2577)
        at androidx.fragment.app.FragmentController.dispatchActivityCreated(FragmentController.java:247)
        at androidx.fragment.app.FragmentActivity.onStart(FragmentActivity.java:541)
        at androidx.appcompat.app.AppCompatActivity.onStart(AppCompatActivity.java:201)
        at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1425)
        at android.app.Activity.performStart(Activity.java:7825)
        at android.app.ActivityThread.handleStartActivity(ActivityThread.java:3294)
        at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:221)
        at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:201)
        at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:173)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:97)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016)
        at android.os.Handler.dispatchMessage(Handler.java:107)
        at android.os.Looper.loop(Looper.java:214)
        at android.app.ActivityThread.main(ActivityThread.java:7356)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
2020-06-07 23:12:41.308 6872-6872/com.enesseval.moviedeneme I/Process: Sending signal. PID: 6872 SIG: 9

Answer 1

您的菜单项应类似于（出于说明目的，我编辑了股票android studio导航项目模板）：

<item
    android:id="@+id/right_menu_spinner"
    android:icon="@drawable/icon_default"
    android:title="Quality"
    app:actionViewClass="androidx.appcompat.widget.AppCompatSpinner"/>

然后在您的活动中访问，而不是片段：

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        // Setup code ...


        // Access Navigation header and menu
        val navView: NavigationView = findViewById(R.id.nav_view)
        (navView.menu.findItem(R.id.right_menu_spinner).actionView as Spinner).run {
            adapter = ArrayAdapter(this@MainActivity, android.R.layout.simple_list_item_1, arrayOf("High", "Medium", "Low"))
        }
    }

}

结果：

Answer 2

使用XML向您添加微调框：

    <RelativeLayout
        android:id="@+id/tilLanguage"
        android:layout_width="match_parent"
        android:layout_height="40dp"
        android:layout_marginStart="35dp"
        android:layout_marginTop="20dp"
        android:layout_marginEnd="35dp"
        android:layout_weight=".28"
        app:layout_constraintTop_toBottomOf="@+id/tvAlmostThere"
        android:background="@drawable/spinner_background"
        android:orientation="horizontal">

        <Spinner
            android:id="@+id/etLanguage"
            android:layout_width="match_parent"
            android:layout_height="40dp"
            android:layout_centerVertical="true"
            android:layout_gravity="center"
            android:layout_marginStart="5dp"
            android:background="@android:color/transparent"
            android:gravity="center"
            android:spinnerMode="dropdown"
            android:focusable="true"
            android:textColorHint="@color/textColorPrimary"/>

        <ImageView
            android:layout_width="40dp"
            android:layout_height="40dp"
            android:layout_alignParentRight="true"
            android:layout_centerVertical="true"
            android:layout_gravity="center"
            android:src="@drawable/dropdown" />

    </RelativeLayout>

添加值字符串：

        <item>Select Language:</item>
        <item>English</item>
        <item>French</item>
    </string-array>

然后将其添加到导航抽屉中：

    Language = (Spinner) root.findViewById(R.id.etLanguage);
        ArrayAdapter<CharSequence> status_adapter = ArrayAdapter.createFromResource(getActivity(), R.array.language_arrays, R.layout._spinner_item);
        language_adapter.setDropDownViewResource(R.layout.simple_spinner_dropdown);
        Language .setAdapter(status_adapter);```

如何在片段中添加微调器的导航抽屉

2 个答案: