android - 地方自动完成返回空点异常

问题描述

我正在尝试在我的代码中放置位置自动完成功能，这是在 MainActivity 中：

@Override
  public boolean onOptionsItemSelected(MenuItem item) {

    switch (item.getItemId()) {
         case R.id.action_searchplace:
        // Initialize the AutocompleteSupportFragment.
        Places.initialize(getApplicationContext(), getString(R.string.google_maps_key));
        PlacesClient placesClient = Places.createClient(this);

        AutocompleteSupportFragment autocompleteFragment = (AutocompleteSupportFragment)
            getSupportFragmentManager().findFragmentById(R.id.autocomplete_fragment);

        // Specify the types of place data to return.
        autocompleteFragment.setPlaceFields(Arrays.asList(Place.Field.ID, Place.Field.NAME));

        // Set up a PlaceSelectionListener to handle the response.
        autocompleteFragment.setOnPlaceSelectedListener(new PlaceSelectionListener() {
          @Override
          public void onPlaceSelected(Place place) {
            // TODO: Get info about the selected place.
            Log.i("Place", "Place: " + place.getName() + ", " + place.getId());
          }

          @Override
          public void onError(Status status) {
            // TODO: Handle the error.
            Log.i("Place", "An error occurred: " + status);
          }
        });
        Toast.makeText(getApplicationContext(), "Working", Toast.LENGTH_LONG).show();
        return true;

这是我的 xml (fragment_searchplace.xml) 文件：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical">
  <com.google.android.material.card.MaterialCardView
      android:layout_width="match_parent"
      android:layout_height="wrap_content">
    <androidx.fragment.app.FragmentContainerView android:id="@+id/autocomplete_fragment"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:name="com.google.android.libraries.places.widget.AutocompleteSupportFragment"
        />
  </com.google.android.material.card.MaterialCardView>
</LinearLayout>

单击菜单项时，出现错误：

 E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.phocast, PID: 8062
    java.lang.NullPointerException: Attempt to invoke virtual method 'com.google.android.libraries.places.widget.AutocompleteSupportFragment com.google.android.libraries.places.widget.AutocompleteSupportFragment.setPlaceFields(java.util.List)' on a null object reference
        at com.example.phocast.MainActivity.onOptionsItemSelected(MainActivity.java:539)
        at android.app.Activity.onMenuItemSelected(Activity.java:4137)
        at androidx.fragment.app.FragmentActivity.onMenuItemSelected(FragmentActivity.java:383)
        at androidx.appcompat.app.AppCompatActivity.onMenuItemSelected(AppCompatActivity.java:219)
        at androidx.appcompat.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:109)
        at androidx.appcompat.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:109)
        at androidx.appcompat.app.ToolbarActionBar$2.onMenuItemClick(ToolbarActionBar.java:64)
        at androidx.appcompat.widget.Toolbar$1.onMenuItemClick(Toolbar.java:207)
        at androidx.appcompat.widget.ActionMenuView$MenuBuilderCallback.onMenuItemSelected(ActionMenuView.java:781)
        at androidx.appcompat.view.menu.MenuBuilder.dispatchMenuItemSelected(MenuBuilder.java:840)
        at androidx.appcompat.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:158)
        at androidx.appcompat.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:991)
        at androidx.appcompat.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:981)
        at androidx.appcompat.widget.ActionMenuView.invokeItem(ActionMenuView.java:625)
        at androidx.appcompat.view.menu.ActionMenuItemView.onClick(ActionMenuItemView.java:151)
        at android.view.View.performClick(View.java:7125)
        at android.view.View.performClickInternal(View.java:7102)
        at android.view.View.access$3500(View.java:801)
        at android.view.View$PerformClick.run(View.java:27336)
        at android.os.Handler.handleCallback(Handler.java:883)
        at android.os.Handler.dispatchMessage(Handler.java:100)
        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)

我在这里做错了什么？

xml 在@santalu 的回答后更新

我已将 xml 文件更新为：

# The activity_main.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_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:openDrawer="start">

    <include
        layout="@layout/app_bar_main"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <com.google.android.material.navigation.NavigationView
        android:id="@+id/nav_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:fitsSystemWindows="true"
        android:theme="@style/ThemeOverlay.AppCompat.navTheme"
        app:headerLayout="@layout/nav_header_main"
        app:menu="@menu/activity_main_drawer" >
    </com.google.android.material.navigation.NavigationView>

</androidx.drawerlayout.widget.DrawerLayout>


#the app_bar_main.xml
<androidx.coordinatorlayout.widget.CoordinatorLayout 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=".MainActivity">
  ....
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical">
    <com.google.android.material.card.MaterialCardView
      android:layout_width="match_parent"
      android:layout_height="wrap_content">
      <androidx.fragment.app.FragmentContainerView android:id="@+id/autocomplete_fragment"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:name="com.google.android.libraries.places.widget.AutocompleteSupportFragment"
        />
    </com.google.android.material.card.MaterialCardView>

没有更多的崩溃，但搜索也没有出现。它只显示吐司。

标签： android

android - 地方自动完成返回空点异常

问题描述

解决方案

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