Android 错误：找不到符号“this.setSupportActionBar（工具栏）；”。我怎样才能解决它？

我使用Android studio 3.1.2。我收到了这个错误消息。我如何解决这个问题

错误：找不到符号this.setSupportActionBartoolbar

我的应用程序build.gradle

apply plugin: 'com.android.application'

    compileSdkVersion 27
    buildToolsVersion '28.0.0 rc1'
    useLibrary 'org.apache.http.legacy'
    defaultConfig {
        applicationId "com.XXXX.XXXX"

        manifestPlaceholders = [onesignal_app_id               : "9dfhdfg-art455-3455-8dfgh45-fghe345340fh45",
                                // Project number pulled from dashboard, local value is ignored.
                                onesignal_google_project_number: "REMOTE"]

        minSdkVersion 16
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
        multiDexEnabled true

        flavorDimensions "default"

        productFlavors {
            dev {
                // Enable pre-dexing to produce an APK that can be tested on
                // Android 5.0+ without the time-consuming DEX build processes.

                dimension "default"

            }
            prod {
                // The actual minSdkVersion for the production version.
                minSdkVersion 16
                dimension "default"
            }
        }
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}
dependencies {
    implementation fileTree(include: ['*.jar'], dir: 'libs')
    testImplementation 'junit:junit:4.12'
    implementation 'com.android.support:appcompat-v7:27.1.1'
    implementation 'com.android.support:support-media-compat:27.1.1'
    implementation 'com.android.support:support-core-utils:27.1.1'
    implementation 'com.android.support:customtabs:27.1.1'
    implementation 'com.android.support:animated-vector-drawable:27.1.1'
    implementation 'com.android.support:design:27.1.1'
    implementation 'com.google.android.gms:play-services-ads:15.0.0'
    implementation 'com.android.support:cardview-v7:27.1.1'
    implementation 'it.neokree:MaterialTabs:0.11'
    implementation files('libs/YouTubeAndroidPlayerApi.jar')
    implementation files('libs/picasso-2.4.0.jar')
    implementation 'de.hdodenhof:circleimageview:1.3.0'
    implementation 'com.onesignal:OneSignal:3.+@aar'
    implementation 'com.android.support:multidex:1.0.3'
    implementation 'com.google.firebase:firebase-core:15.0.0'
    implementation 'com.google.android.gms:play-services-analytics:15.0.0'
    implementation 'com.android.support:gridlayout-v7:27.1.1'
    implementation 'com.android.support:recyclerview-v7:27.1.1'
}

apply plugin: 'com.google.gms.google-services'

我的错误Java页面：

import android.content.Intent;
import android.os.AsyncTask;
import android.os.Build;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.SearchView;
import android.support.v7.widget.Toolbar;

public class CategoryItem extends ActionBarActivity {


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.category_item_grid);
        toolbar = (Toolbar) this.findViewById(R.id.toolbar);
        toolbar.setTitle(Constant.CATEGORY_TITLE);
        this.setSupportActionBar(toolbar);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
        getSupportActionBar().setDisplayShowHomeEnabled(true);
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            getWindow().addFlags(WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS);
            getWindow().setStatusBarColor(getResources().getColor(R.color.colorPrimaryDark));
        }

它还显示以下错误消息：

无法解决方法“setSupportAcationBar”导入 android.support.v7.widget.Toolbar

---

我怎样才能解决它？。解决方案是什么？。任何人

使用AppCompatActivity而不是ActionBarActivity

ActionBarActivity已死亡。谢谢。它起作用了