[android] setSupportActionBar toolbar cannot be applied to (android.widget.Toolbar) error

I've been looking for an answer and I've tried many possible solutions, but nothing seems to work..

I'm trying to setup a Material Action Bar following this tutorial.

Here's my code:

tool_bar.xml:

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/ColorPrimary"
    android:elevation="4dp">

</android.support.v7.widget.Toolbar>

activity.xml:

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#FFFFFF">
    <!-- The main content view -->
    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <include
            android:id="@+id/app_bar"
            layout="@layout/tool_bar" />
    </RelativeLayout>
    <!-- Navigation Drawer -->
    <ListView
        android:id="@+id/left_drawer"
        android:layout_width="220dp"
        android:layout_height="match_parent"
        android:layout_gravity="left"
        android:background="#1C1C1C"
        android:divider="@android:color/darker_gray"
        android:dividerHeight="1dp" />

</android.support.v4.widget.DrawerLayout>

And finally my activity.java:

import android.app.ActionBar;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toolbar;


public class rutaActivity extends ActionBarActivity {

private Toolbar toolbar;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_ruta);

        getSupportActionBar().hide();//Ocultar ActivityBar anterior

        toolbar = (Toolbar) findViewById(R.id.app_bar);
        setSupportActionBar(toolbar); //HERE'S THE PROBLEM !!!!

Error:

setSupporActionBar (android.support.v7.widget.Toolbar) in ActionBarActivity cannot be applied to (android.widget.Toolbar)

How can I fix this?

Certify that your Manifest declaration includes android:theme="@style/AppTheme.NoActionBar" tag, like the following:

<activity
    android:name=".PointsScreen"
    android:theme="@style/AppTheme.NoActionBar">
</activity>

In You MainActivity.java import android .support.v7.widget.Toolbar insert of java program

For Android version above 3:

import androidx.appcompat.widget.Toolbar;

For Android version below 3:

import android.widget.Toolbar;

I was using previously this code:

Toolbar toolbar =  findViewById(R.id.toolbar);
setSupportActionBar(toolbar);

and extended AppCompatActivity also but I was getting the same error. So in place of using Toolbar class, I have imported the below class and it worked for me:

android.support.v7.widget.Toolbar

With the addition of androidx in Studio 3.0+ the Toolbar compatibility is now in a new library, accessible like this

import androidx.appcompat.widget.Toolbar

class must be extend of AppCompatActivity to resolve the problem of setSuppertActionBar that is not recognizable

import android.support.v7.widget.Toolbar;

import it into your java class

ToolBar's name can easily be changed using

android:label="My Activity"

in your Manifest File. I just going through Manifest & found

android:label 

Helps to change according to the specific activity, Hope you'll give it a try

For adding a ToolBar that supports Material Design, the official documentation directions are probably the best to follow.

1. Add the v7 appcompat support library.

2. Make your activity extend AppCompatActivity.

   public class MyActivity extends AppCompatActivity {
     // ...
   }
   

3. Declare NoActionBar in the Manifest.

   <application
       android:theme="@style/Theme.AppCompat.Light.NoActionBar"
       />
   

4. Add a toolbar to your activity's xml layout.

   <android.support.v7.widget.Toolbar
      android:id="@+id/my_toolbar"
      android:theme="@style/ThemeOverlay.AppCompat.ActionBar"
      ...
      />
   

5. Call setSupportActionBar in the activity's onCreate.

   @Override
   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_my);
       Toolbar myToolbar = (Toolbar) findViewById(R.id.my_toolbar);
       setSupportActionBar(myToolbar);
   }
   

Note: You will have to import the following in the activity.

import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;

In using toolbar you should extends AppCompatActivity and

import android.support.v7.widget.Toolbar 

Adding import android.support.v7.widget.Toolbar to the import list resolve this issue.

Then add the toolbar widget layout file:

<android.support.v7.widget.Toolbar
    android:id="@+id/list_toolbar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="?attr/colorPrimary"
    android:minHeight="?attr/actionBarSize"
    android:theme="?attr/actionBarTheme"
    />

In onCreate method of java code

//call to

Tootbar toolbar = findViewById(R.id.toolbar); setSupportActionBar(toolbar);

Source: https://developer.android.com/training/appbar/up-action

Just change

import android.widget.Toolbar;

To

import android.support.v7.widget.Toolbar;