android error:cannot find symbol variable

Question

I am making my first testing program with Android Studio.

The program has two activities, you insert one text in the first activity, push one button, and then the text is showed on another activity.

I am following one tutorial on YT but I find two errors:

cannot find symbol variable and I can´t find the solution.

I have searched here in SO but no answer works. I have tried:

• Clean Project and rebuild Project.

• I have no "import android.R".

• I have used import mypackagename.R but it tells me "unused import statement".

• I have changed the ID names and removed every capital letters, since I have read it causes troubles.

• I have performed a Gradle sync (via Tools > Android > Sync Project with Gradle Files).

Codes are:

MainActivity.java:

    package pack1.p1;

    import android.support.v7.app.AppCompatActivity;
    import android.os.Bundle;
    import android.widget.Button;
    import android.widget.EditText;

    public class MainActivity extends AppCompatActivity 
    {

      @Override
      protected void onCreate(Bundle savedInstanceState)
      {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button boton1;
        EditText texto1;

        boton1=(Button)findViewById(R.layout.idboton1);

        texto1=(EditText)findViewById(R.layout.edittext1);






      }
    }

activity_main.xml:

    <?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
      android:id="@+id/activity_main"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:paddingBottom="@dimen/activity_vertical_margin"
      android:paddingLeft="@dimen/activity_horizontal_margin"
      android:paddingRight="@dimen/activity_horizontal_margin"
      android:paddingTop="@dimen/activity_vertical_margin"
      tools:context="pack1.p1.MainActivity">

    <TextView
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:text="PRIMERA VENTANA"
      android:id="@+id/textview1" />

    <EditText
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:inputType="textPersonName"
      android:text="Name"
      android:ems="10"
      android:layout_below="@+id/textview1"
      android:layout_alignParentLeft="true"
      android:layout_alignParentStart="true"
      android:layout_marginLeft="11dp"
      android:layout_marginStart="11dp"
      android:layout_marginTop="39dp"
      android:id="@+id/edittext1" />

    <Button
      android:text="Abrir ventana nueva"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_below="@+id/edittext1"
      android:layout_centerHorizontal="true"
      android:layout_marginTop="52dp"
      android:id="@+id/idboton1" />

    </RelativeLayout>

activity_main2.xml:

<?xml version="1.0" encoding="utf-8"?>

  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:fitsSystemWindows="true"
  tools:context="pack1.p1.Main2Activity">

<android.support.design.widget.AppBarLayout
   android:layout_width="match_parent"
   android:layout_height="wrap_content"
   android:theme="@style/AppTheme.AppBarOverlay">

   <android.support.v7.widget.Toolbar
     android:id="@+id/toolbar"
     android:layout_width="match_parent"
     android:layout_height="?attr/actionBarSize"
     android:background="?attr/colorPrimary"
     app:popupTheme="@style/AppTheme.PopupOverlay" />

</android.support.design.widget.AppBarLayout>

<include layout="@layout/content_main2" />

<android.support.design.widget.FloatingActionButton
  android:id="@+id/fab"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_gravity="bottom|end"
  android:layout_margin="@dimen/fab_margin"
  app:srcCompat="@android:drawable/ic_dialog_email" />

content_main2.xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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/content_main2"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:paddingBottom="@dimen/activity_vertical_margin"
   android:paddingLeft="@dimen/activity_horizontal_margin"
   android:paddingRight="@dimen/activity_horizontal_margin"
   android:paddingTop="@dimen/activity_vertical_margin"
   app:layout_behavior="@string/appbar_scrolling_view_behavior"
   tools:context="pack1.p1.Main2Activity"
   tools:showIn="@layout/activity_main2">

</RelativeLayout>

And finally, the AndroidManifest.xml:

<?xml version="1.0" encoding="utf-8"?>

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <activity android:name=".MainActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity
        android:name=".Main2Activity"
        android:label="@string/title_activity_main2"
        android:theme="@style/AppTheme.NoActionBar"></activity>
</application>

This is where I have looked for:

Android Studio: Gradle: error: cannot find symbol variable

Android Studio cannot find symbol variable

Android Gradle: can't find symbol variable

Answer 1

In MainActivity.java, R.id.idboton1 instead of R.layout.idboton1. Same with edittext1