Getting a Null object reference on SearchView

Question

I am making an android app in which i added a menu file where i added an item to perform search. Then on the MainActivity i added a searchView variable which i am trying to inflate in the onCreatOptionsmenu() method. When i try to run the app i get this error, "java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.SearchView.setSearchableInfo(android.app.SearchableInfo)' on a null object reference"

Here is the code to my menu main.xml

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">
        <item
            android:title="@string/search"
            android:orderInCategory="1"
            app:showAsAction ="ifRoom"
            android:id="@+id/action_search"
            />

</menu>

MainActivity code for searchview

public class MainActivity extends AppCompatActivity {
private SearchView searchView;
 @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.main, menu);
        SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
        searchView = (SearchView) menu.findItem(R.id.action_search)
                .getActionView();
        searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
        searchView.setMaxWidth(Integer.MAX_VALUE);

        searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
            @Override
            public boolean onQueryTextSubmit(String query) {
                mCorona_Stats_Adapter.getFilter().filter(query);
                return false;
            }

            @Override
            public boolean onQueryTextChange(String newText) {
                mCorona_Stats_Adapter.getFilter().filter(newText);
                return false;
            }
        });
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(@NonNull MenuItem item) {
        int menuItemThatWasSelected = item.getItemId();
        if(menuItemThatWasSelected == R.id.action_search){
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    @Override
    public void onBackPressed() {
        if (!searchView.isIconified()) {
            searchView.setIconified(true);
            return;
        }
        super.onBackPressed();
    }
}

build.gradle

apply plugin: 'com.android.application'

android {
    compileSdkVersion 29
    buildToolsVersion "29.0.2"
    defaultConfig {
        applicationId "com.passengerearth.coronago"
        minSdkVersion 15
        targetSdkVersion 29
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'androidx.appcompat:appcompat:1.0.2'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    implementation 'com.google.android.material:material:1.0.0'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test.ext:junit:1.1.0'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
}

Answer 1

AndroidX replaces the original support library APIs with packages in the androidx namespace.

You are using androidx. So add androidx support.

 <item
    android:id="@+id/action_search"
    .....................
    app:actionViewClass="androidx.appcompat.widget.SearchView" />

And import below in MainActivity section.

import androidx.appcompat.widget.SearchView;