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Unable to change TextView text with string passed using intent

I make a very simple login screen where the user enters his username and password, presses the login button, and then the inputs are displayed on the next screen.

I get NullPointerExceptionevery time I try to change the textview values. I searched the Internet for a long time and did not come up with anything, and it should be something simple that I’m just completely absent.

Below is my code:

public class LoggedIn extends Activity{
    String username = "";
    String password = "";

    TextView name;
    TextView pwd;

    Button infoDisp;

    protected void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.logged_in);

        Intent intent = getIntent();
        name = (TextView)findViewById(R.id.username);
        pwd = (TextView)findViewById(R.id.password);

        username = intent.getStringExtra("nameInfo");
        password = intent.getStringExtra("passInfo");

        name.setText(username);
        pwd.setText(password);

    }
}

Edit: I changed the node to the intention above, also here the rest of the code (first activity)

public class LoginActivity extends Activity {

    Button loginBtn;
    Button registerBtn;
    EditText username;
    EditText pword;
    static String name;
    static String pass;

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

        username = (EditText) this.findViewById(R.id.username);
        pword = (EditText) this.findViewById(R.id.password);
        loginBtn = (Button) this.findViewById(R.id.loginBtn);

        loginBtn.setOnClickListener(new OnClickListener() {

            public void onClick(View arg0){
                Intent intent = new Intent(LoginActivity.this, LoggedIn.class);
                name = username.getText().toString();
                pass = pword.getText().toString();
                intent.putExtra("nameInfo", name);
                intent.putExtra("passInfo", pass);
                startActivity(intent);
            }
        });

    }

}

, , . , , - EditText, , ... ?

StackTrace:

FATAL EXCEPTION: main
Process: com.example.loginscreen, PID: 1677
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.loginscreen/com.example.loginscreen.LoggedIn}: java.lang.NullPointerException
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2176)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2226)
    at android.app.ActivityThread.access$700(ActivityThread.java:135)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1397)
    at android.os.Handler.dispatchMessage(Handler.java:102)
    at android.os.Looper.loop(Looper.java:137)
    at android.app.ActivityThread.main(ActivityThread.java:4998)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:515)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:777)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:593)
    at dalvik.system.NativeStart.main(Native Method)
 Caused by: java.lang.NullPointerException
    at com.example.loginscreen.LoggedIn.onCreate(LoggedIn.java:30)
    at android.app.Activity.performCreate(Activity.java:5243)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2140)
    ... 11 more

Aaaand xml: activity_login:

<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=".LoginActivity" >

<TextView
    android:id="@+id/textView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentLeft="true"
    android:text="Login:"
    android:textAppearance="?android:attr/textAppearanceMedium" />

<TextView
    android:id="@+id/textView2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignLeft="@+id/textView1"
    android:layout_below="@+id/textView1"
    android:layout_marginTop="38dp"
    android:text="Password:"
    android:textAppearance="?android:attr/textAppearanceMedium" />

<EditText
    android:id="@+id/username"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_above="@+id/textView2"
    android:layout_alignParentTop="true"
    android:layout_marginLeft="20dp"
    android:layout_toRightOf="@+id/textView1"
    android:ems="10" />

<EditText
    android:id="@+id/password"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignBottom="@+id/textView2"
    android:layout_alignParentRight="true"
    android:layout_toRightOf="@+id/textView2"
    android:ems="10"
    android:inputType="textPassword" >

    <requestFocus />
</EditText>

<Button
    android:id="@+id/loginBtn"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignLeft="@+id/textView2"
    android:layout_below="@+id/textView2"
    android:layout_marginTop="26dp"
    android:text="Login" />

<Button
    android:id="@+id/registerBtn"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignBaseline="@+id/loginBtn"
    android:layout_alignBottom="@+id/loginBtn"
    android:layout_alignLeft="@+id/textView3"
    android:layout_marginLeft="46dp"
    android:text="Register" />

<CheckBox
    android:id="@+id/remPass"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignLeft="@+id/loginBtn"
    android:layout_below="@+id/loginBtn"
    android:layout_marginTop="19dp"
    android:text="Remember Password" />

<TextView
    android:id="@+id/textView3"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/remPass"
    android:layout_marginTop="28dp"
    android:layout_toRightOf="@+id/textView1"
    android:text="Forgot Password" />

logged_in:

<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=".LoginActivity" >

<TextView
    android:id="@+id/textView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true"
    android:text="Logged In!"
    android:textAppearance="?android:attr/textAppearanceLarge" />

<TextView
    android:id="@+id/textView2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/textView1"
    android:layout_marginTop="56dp"
    android:text="Username: "
    android:textAppearance="?android:attr/textAppearanceLarge" />

<TextView
    android:id="@+id/textView3"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignLeft="@+id/textView2"
    android:layout_below="@+id/textView2"
    android:layout_marginTop="56dp"
    android:text="Password: "
    android:textAppearance="?android:attr/textAppearanceLarge" />

<TextView
    android:id="@+id/recUsername"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignBottom="@+id/textView2"
    android:layout_marginLeft="33dp"
    android:layout_toRightOf="@+id/textView2"
    android:editable="true"
    android:text=" "
    android:textAppearance="?android:attr/textAppearanceLarge" />

<TextView
    android:id="@+id/recPassword"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignBottom="@+id/textView3"
    android:layout_alignRight="@+id/textView4"
    android:editable="true"
    android:text=" "
    android:textAppearance="?android:attr/textAppearanceLarge" />

<Button
    android:id="@+id/infoBtn"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignLeft="@+id/textView1"
    android:layout_alignRight="@+id/textView1"
    android:layout_below="@+id/textView3"
    android:layout_marginTop="62dp"
    android:text="Press to Display Info" />

+3
6

, id TextView s ..

    username = (TextView) this.findViewById(R.id.username);
    pword = (TextView) this.findViewById(R.id.password);


    username = (TextView) this.findViewById(R.id.recUsername);
    pword = (TextView) this.findViewById(R.id.recPassword);
+2

LoggedIn. logged_in.xml

    username = (EditText) this.findViewById(R.id.username);
    pword = (EditText) this.findViewById(R.id.password);
    loginBtn = (Button) this.findViewById(R.id.loginBtn);


    TextView username = (TextView)findViewById(R.id.recUsername);
    TextView pword = (TextView)findViewById(R.id.recPassword);
    loginBtn = (Button)findViewById(R.id.infoBtn);
+1

 name = (TextView)findViewById(R.id.username);
 pwd = (TextView)findViewById(R.id.password);


 name = (TextView)findViewById(R.id.recUsername);
 pwd = (TextView)findViewById(R.id.recPassword);

LoggedIn.java

NUllPointerExceptipon - ccoz, . findViewById . . NullPointerExcpetion.

+1

...

Bundle bundle = getIntent().getExtras();

...

Intent bundle = getIntent();

, ....

username = bundle.getStringExtra("nameInfo");
password = bundle.getStringExtra("passInfo");

Update:

You are trying to get TextViewusing those idthat do not exist in the current xml layout ... that is, you are using the wrong one idto extract TextViews. So, change those idin the following lines ...

username = (TextView) this.findViewById(R.id.username);
pword = (TextView) this.findViewById(R.id.password);

to

username = (TextView) this.findViewById(R.id.recUsername);
pword = (TextView) this.findViewById(R.id.recPassword);
0
source

I think there is a problem with the following line

     Intent intent = new Intent(LoginActivity.this, LoggedIn.class);

change it to

     Intent intent = new Intent(this, LoggedIn.class);

or

 Intent intent = new Intent(getApplicationContext(), LoggedIn.class);
0
source

In your LoggedIn class, identifiers are invalid

name = (TextView)findViewById(R.id.username);
pwd = (TextView)findViewById(R.id.password);

change the above identifiers to the specific identifiers in the logged_in.xml layout and try again

0
source

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