获取错误“你需要使用Theme.AppCompat主题（或后代）”即使我使用Theme.AppCompat

Question

就像标题所说，即使我正在使用 You need to use a Theme.AppCompat theme (or descendant) with this，我仍然会收到错误Theme.AppCompat。

首先，这是得到错误的类（注意：我用注释标记了错误发生的行）：

public class CustomSimpleCursorAdapter extends SimpleCursorAdapter {

    private Context context;
    private Cursor cursor;
    private MainActivity mainActivity;

    public CustomSimpleCursorAdapter(Context context, int layout, Cursor cursor, String[] from, int[] to, int flags, MainActivity mainActivity) {
        super(context, layout, cursor, from, to, flags);
        this.context = context;
        this.cursor = cursor;
        this.mainActivity = mainActivity;
    }

    @Override
    public View getView(final int position, View convertView, ViewGroup parent){

        // Grab each row as it is pulled from the db.
        DatabaseHelper dbHelper = new DatabaseHelper(context);
        View row = super.getView(position, convertView, parent);

        cursor.moveToPosition(position);
        final Integer id = cursor.getInt(cursor.getColumnIndex("_id"));
        final String personID = cursor.getString(cursor.getColumnIndex("personid"));

        // Set alternating rows to different colors.
        if(position % 2 == 0){
            row.setBackgroundColor(Color.parseColor(Constants.WHITE));
        } else {
            row.setBackgroundColor(Color.parseColor(Constants.LIGHTGREY));
        }

        // Make the delete button clickable.
        Button deletePersonButton = (Button)row.findViewById(R.id.remove_person);
        deletePersonButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                AlertDialog.Builder deleteDialogBuilder = new AlertDialog.Builder(context);
                deleteDialogBuilder.setTitle("Delete Person " + personID + "?");
                deleteDialogBuilder.setMessage("This process is IRREVERSABLE!");
                deleteDialogBuilder.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        DatabaseHelper databaseHelper = new DatabaseHelper(context);
                        databaseHelper.deletePerson(personID);
                        mainActivity.dataChanged();
                        Toast.makeText(context, "Person " + personID + " (ID: " + Integer.toString(id) + ") Deleted", Toast.LENGTH_LONG).show();
                    }
                });
                deleteDialogBuilder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.dismiss();
                    }
                });
                AlertDialog deleteDialog = deleteDialogBuilder.create();
                deleteDialog.setIcon(R.drawable.warning);
                deleteDialog.show(); // This is where I get the error
            }
        });

        return row;
    }
}

这是我调用CustomSimpleCursorAdapter的地方：

public class Home extends Fragment{

    private MainActivity mainActivity;
    private View rootView;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
        rootView = inflater.inflate(R.layout.home, container, false);
        mainActivity = (MainActivity)getActivity();
        return rootView;
    }

    @Override
    public void onViewCreated(View rootView, Bundle savedInstanceState) {
        super.onViewCreated(rootView, savedInstanceState);
        drawThePersonView();
    }

    public void drawThePersonView(){
        Context context = mainActivity.getApplicationContext();
        DatabaseHelper myDBHelper = new DatabaseHelper(context);
        Cursor personCursor = myDBHelper.getUndeletedCasualtiesCursor();
        String[] fromColumns = {"_id","personID","location","status"};
        int[] toViews = {R.id.person_number_textview, R.id.person_personID_textview, R.id.person_location_textview, R.id.person_status_textview};
        CustomSimpleCursorAdapter mySimpleCursorAdapter = new CustomSimpleCursorAdapter(context, R.layout.person_layout, personCursor, fromColumns, toViews, 0, mainActivity);

        ListView myListView = (ListView) rootView.findViewById(R.id.person_row);

        // Draw the list
        myListView.setAdapter(mySimpleCursorAdapter);

        myDBHelper.close();
    }
}

这是我的 AndroidManifest.xml 文件：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.domain">

    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

    <application
        android:allowBackup="true"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme"
        android:name="com.domain.MyApplication">
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name"
            android:theme="@style/AppTheme.NoActionBar"
            android:windowSoftInputMode="adjustPan|stateHidden">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity
            android:name=".forms.Form01"
            android:label="@string/form_01_title"
            android:theme="@style/AppTheme.NoActionBar"
            android:windowSoftInputMode="adjustPan|stateHidden" />
        <activity
            android:name=".forms.Form02"
            android:label="@string/form_02_title"
            android:theme="@style/AppTheme.NoActionBar"
            android:windowSoftInputMode="adjustPan|stateHidden" />
        <activity
            android:name=".forms.Form03"
            android:label="@string/form_03_title"
            android:theme="@style/AppTheme.NoActionBar"
            android:windowSoftInputMode="adjustPan|stateHidden" />
        <activity
            android:name=".AddPerson"
            android:label="@string/title_activity_add_person"
            android:theme="@style/AppTheme.NoActionBar" />
        <activity
            android:name=".AddItem"
            android:label="@string/title_activity_add_item"
            android:theme="@style/AppTheme.NoActionBar" />

    </application>

</manifest>

在我发布的上述清单中，没有提及Theme.AppCompat，但我在发布此之前确实做了更改。我一次更改了一个，然后我将它们全部更改为Theme.AppCompat并且我仍然每次都收到错误，即使我正在使用 Theme.AppCompat。< / p>

这是错误的logcat：

09-01 13:07:09.457 26231-26231/com.domain E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.domain, PID: 26231
    java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
        at android.support.v7.app.AppCompatDelegateImplV7.createSubDecor(AppCompatDelegateImplV7.java:309)
        at android.support.v7.app.AppCompatDelegateImplV7.ensureSubDecor(AppCompatDelegateImplV7.java:278)
        at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:252)
        at android.support.v7.app.AppCompatDialog.setContentView(AppCompatDialog.java:76)
        at android.support.v7.app.AlertController.installContent(AlertController.java:216)
        at android.support.v7.app.AlertDialog.onCreate(AlertDialog.java:240)
        at android.app.Dialog.dispatchOnCreate(Dialog.java:373)
        at android.app.Dialog.show(Dialog.java:274)
        at com.domain.adapters.CustomSimpleCursorAdapter$1.onClick(CustomSimpleCursorAdapter.java:57)
        at android.view.View.performClick(View.java:4780)
        at android.view.View$PerformClick.run(View.java:19866)
        at android.os.Handler.handleCallback(Handler.java:739)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:135)
        at android.app.ActivityThread.main(ActivityThread.java:5258)
        at java.lang.reflect.Method.invoke(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:372)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)

有什么建议吗？

谢谢！

Answer 1

只需将getApplicationContext()更改为getContext()。

public void drawThePersonView(){ 
        Context context = getContext();
        ...
        // your stuff
        ...
} 

我还没有测试过这段代码。请测试并告诉我。

更多阅读Understanding Context In Android Application。

我希望它有所帮助。

Answer 2

这个问题已经发生在我身上 这是因为在样式不是(Theme.AppCompat)的活动中使用“警报”对话框构建器 我将样式更改为Theme.AppCompat但仍无法正常工作 我注意到当你改变活动的风格时android studio有问题所以我建议你复制与你的活动相关的java和xml的代码 然后删除活动，然后使用相同的java和xml再次重新创建它，但样式为Theme.AppCompat 可能有效的另一个解决方案是，您可以进行要构建的对话的活动，而不是进行警报对话 它更易于使用，在清单文件中，您可以将主题设置为对话活动，如android:theme="@style/Base.Theme.AppCompat.Dialog"，以便您创建的对话活动显示为对话