Open second Activity error in Android Studio

Question

I was trying to make small application of two activities but it gives me a code error...............................................................................................................................................................................................................................................

the error

Main activity Java code:

package com.example.amr.startnewactivity;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity
{
    private Button op_btn;


    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        onClickButtonListener();
    }
    public void onClickButtonListener()
    {
        op_btn= (Button)findViewById(R.id.button);
        op_btn.setOnClickListener(
                new View.OnClickListener()
                {
                    @Override
                    public void onClick(View v)
                    {
                        Intent intent = new Intent(".secondActivity");
                        startActivity(intent);

                    }
                }
        );
    }
}

Second Activity Java code:

package com.example.amr.startnewactivity;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

public class secondActivity extends AppCompatActivity {

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

Android manifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.amr.startnewactivity">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        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=".secondActivity"></activity>
        <intent-filter>
            <action android:name=".secondActivity" />

            <category android:name="android.intent.category.DEFAULT" />
        </intent-filter>
    </application>

</manifest>

Main activity.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <Button
        android:id="@+id/button"
        android:layout_width="152dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="116dp"
        android:layout_marginLeft="116dp"
        android:layout_marginTop="248dp"
        android:text="open"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>

Second activity .xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".secondActivity">

</android.support.constraint.ConstraintLayout>

Check out this documentation on the official Android Developer docs which covers this very topic of starting another activity: https://developer.android.com/training/basics/firstapp/starting-activity — Edric, Oct 02 '18 at 07:58

Sniffer · Answer 1 · 2018-10-02T07:53:43.377

1

add this code to your button click

Intent intent = new Intent(MainActivity.this,secondActivity.class);
startActivity(intent);

OR

startActivity(new Intent(MainActivity.this,secondActivity.class))

And try to follow the naming conventions in Java. Look at here

edited Oct 02 '18 at 07:53

answered Oct 02 '18 at 07:52

Sniffer

1,495
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Can you post your logcat – Sniffer Oct 02 '18 at 07:53

score 1 · Answer 2 · answered Oct 02 '18 at 07:52

1

did you try this?

Intent intent = new Intent(MainActivity.this,secondActivity.class);
startActivity(intent);

answered Oct 02 '18 at 07:52

Farrokh

1,167
1
7
18

Edric · Answer 3 · 2018-10-02T08:10:10.913

What you're looking for is Intent(Context context, Class<?> class):

startActivity(new Intent(MainActivity.this, SecondActivity.class);

Or:

Intent secondActivityIntent = new Intent(MainActivity.this, SecondActivity.class);
startActivity(secondActivityIntent);

For more information, check out the documentation ("Start another activity").

A second note: Consider removing the <intent-filter> from your AndroidManifest.xml file for secondActivity. This declares a filter for other apps to access programmatically.

In this case, you don't actually need it if you're using an Activity. This is typically used for Intents.

Open second Activity error in Android Studio

3 Answers3