getting fatal exception in android app

Question

I'm making an application where i'm trying to get object of edittext but it is returning null and fatal exception is raised because of this.

translateActivity.java

package diverse.technologies.transcriber;

public class translateActivity extends AppCompatActivity {

Button go;
TextView tv;
EditText et;
TableLayout tl,tml;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    Display display = getWindowManager().getDefaultDisplay();
    Point size = new Point();
    display.getSize(size);
    int width = size.x;
    int height = size.y;

    tl = (TableLayout) findViewById(R.id.tablelayouttexthistory);
    tml = (TableLayout) findViewById(R.id.tablemainlayout);
    et = (EditText) findViewById(R.id.entertext);
    tv = (TextView) findViewById(R.id.textView2);
    go = (Button) findViewById(R.id.button);
    et.clearFocus();
    if(tml.requestFocus())
        Log.d("focus","got on table");
    else
        Log.d("focus","couldn't get");
    showhistory();   //showing history

    //other code
}

activity_translate.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: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="diverse.technologies.transcriber.translateActivity">

    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:fillViewport="true">

        <TableLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/tablemainlayout">

            <TableRow
                android:id="@+id/tableRow1"
                android:layout_width="match_parent"
                android:layout_height="match_parent" >

                <EditText
                    android:layout_height="89dp"
                    android:id="@+id/entertext"
                    android:text="Enter Text(English)"
                    android:layout_marginTop="20dp"
                    android:layout_width="206dp" />

                <Button
                    style="?android:attr/buttonStyleSmall"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:text="Go"
                    android:id="@+id/button"
                    android:gravity="left|center_vertical"
                    android:layout_marginTop="22dp" />
            </TableRow>

            <TableRow
                android:id="@+id/tableRow2"
                android:layout_width="match_parent"
                android:layout_height="match_parent" >

                <TextView
                    android:layout_width="280dp"
                    android:layout_height="wrap_content"
                    android:text="Translated Text(Gujarati)"
                    android:id="@+id/textView2"
                    android:layout_row="1"
                    android:layout_columnSpan="2"
                    android:layout_marginTop="7dp"
                    android:textSize="25dp"
                    android:layout_span="2" />

            </TableRow>

            <TableRow
                android:id="@+id/tableRow3"
                android:layout_width="match_parent"
                android:layout_height="match_parent" >

                <TableLayout
                    android:id="@+id/tablelayouttexthistory"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_span="2">
                </TableLayout>
            </TableRow>

        </TableLayout>

    </ScrollView>

</RelativeLayout>

Exception that I'm getting:

E/AndroidRuntime: FATAL EXCEPTION: main Process: diverse.technologies.transcriber, PID: 4447 java.lang.RuntimeException: Unable to start activity ComponentInfo{diverse.technologies.transcriber/diverse.technologies.transcriber.translateActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.EditText.clearFocus()' on a null object reference at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2509) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2569) at android.app.ActivityThread.access$900(ActivityThread.java:150) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1399) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:168) at android.app.ActivityThread.main(ActivityThread.java:5885) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:797) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:687) Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.EditText.clearFocus()' on a null object reference at diverse.technologies.transcriber.translateActivity.onCreate(translateActivity.java:59) at android.app.Activity.performCreate(Activity.java:6262) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1125) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2462) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2569) at android.app.ActivityThread.access$900(ActivityThread.java:150) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1399) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:168) at android.app.ActivityThread.main(ActivityThread.java:5885) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:797) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:687)

Please help. I'm so stuck here..

java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.EditText.clearFocus()' on a null object reference — Charuක
but why it is returning a null pointer when i'm getting it correctly with the corrrect id ?This method works fine in other activities. @Charuක — Abhishek Panjabi

Passiondroid Passiondroid · Accepted Answer · 2017-02-26T07:24:19

You are not setting the content view of the activity and directly finding the view.

Set it using

setContentView(R.layout.activity_translate);

getting fatal exception in android app

2 Answers