Error initializing Button. What could be the problem?

Question

Java

Here is the xml markup:

<?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: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=".Controller.GameActivity"
    android:background="@drawable/wood_boards_002">
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:id="@+id/textView"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:textSize="25sp"
        android:textColor="#000000"
        android:layout_marginTop="20dp"/>

    <TableLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true">

        <TableRow
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <Button
                android:layout_width="100dp"
                android:layout_height="100dp"
                android:id="@+id/point0_0"
                android:textSize="75sp"
                android:textStyle="bold"
                android:layout_margin="5dp"
                android:background="#ae969696"
                android:onClick="clickPoint0_0"/>

            <Button
                android:layout_width="100dp"
                android:layout_height="100dp"
                android:id="@+id/point0_1"
                android:textSize="75sp"
                android:textStyle="bold"
                android:layout_margin="5dp"
                android:background="#ae969696"
                android:onClick="clickPoint0_1"/>

            <Button
                android:layout_width="100dp"
                android:layout_height="100dp"
                android:id="@+id/point0_2"
                android:textSize="75sp"
                android:textStyle="bold"
                android:layout_margin="5dp"
                android:background="#ae969696"
                android:onClick="clickPoint0_2"/>

        </TableRow>
        Дальше аналогично
 </TableLayout>

</RelativeLayout>

In the GameActivity class:

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

        mIntent = getIntent();
        mStringDifficultyMode = mIntent.getStringExtra(Constants.KEY_INPUT_VALUE_WHEN_CALLED_GAME_ACTIVITY);

        initViews();

        if (mButtons[0][0].getText().equals("")) {
            mTextView.setText("Работает!");
        }
    }
       private void initViews() {
        mButtons[0][0] = (Button) findViewById(R.id.point0_0);
        mButtons[0][1] = (Button) findViewById(R.id.point0_1);
        mButtons[0][2] = (Button) findViewById(R.id.point0_2);
        mButtons[1][0] = (Button) findViewById(R.id.point1_0);
        mButtons[1][1] = (Button) findViewById(R.id.point1_1);
        mButtons[1][2] = (Button) findViewById(R.id.point1_2);
        mButtons[2][0] = (Button) findViewById(R.id.point2_0);
        mButtons[2][1] = (Button) findViewById(R.id.point2_1);
        mButtons[2][2] = (Button) findViewById(R.id.point2_2);
        mTextView = (TextView) findViewById(R.id.textView);
    }

Gives an NPE error:

07-22 04:54:48.679 5836-5836/com.example.root.tick_tack_toe E/AndroidRuntime: FATAL EXCEPTION: main
                                                                              Process: com.example.root.tick_tack_toe, PID: 5836
                                                                              java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.root.tick_tack_toe/com.example.root.tick_tack_toe.Controller.GameActivity}: java.lang.NullPointerException: Attempt to read from null array
                                                                                  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
                                                                                  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
                                                                                  at android.app.ActivityThread.-wrap11(ActivityThread.java)
                                                                                  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
                                                                                  at android.os.Handler.dispatchMessage(Handler.java:102)
                                                                                  at android.os.Looper.loop(Looper.java:148)
                                                                                  at android.app.ActivityThread.main(ActivityThread.java:5417)
                                                                                  at java.lang.reflect.Method.invoke(Native Method)
                                                                                  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
                                                                                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
                                                                               Caused by: java.lang.NullPointerException: Attempt to read from null array
                                                                                  at com.example.root.tick_tack_toe.Controller.GameActivity.initViews(GameActivity.java:48)
                                                                                  at com.example.root.tick_tack_toe.Controller.GameActivity.onCreate(GameActivity.java:38)
                                                                                  at android.app.Activity.performCreate(Activity.java:6237)
                                                                                  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107)
                                                                                  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2369)
                                                                                  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476) 
                                                                                  at android.app.ActivityThread.-wrap11(ActivityThread.java) 
                                                                                  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344) 
                                                                                  at android.os.Handler.dispatchMessage(Handler.java:102) 
                                                                                  at android.os.Looper.loop(Looper.java:148) 
                                                                                  at android.app.ActivityThread.main(ActivityThread.java:5417) 
                                                                                  at java.lang.reflect.Method.invoke(Native Method) 
                                                                                  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) 
                                                                                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 

The line GameActivity.java:48

mButtons[0][0] = (Button) findViewById(R.id.point0_0);

Line GameActivity.java:38
initViews();
Recently I started to study android and here it is. What could be wrong?

Answer 1

I'm an idiot. Array has no size specified)