Replace the below line code:

import android.view.View.OnClickListener; public class MainActivity extends Activity implements OnClickListener{ 

Place the below method in your MainActivity.java

 public void onClick(View v) { if(v.getId==R.id.button1){ Intent i = new Intent(FromActivity.this, ToActivity.class); startActivity(i); } } 

Add the below lines in your manifest file:

 <activity android:name="com.packagename.FromActivity"></activity> <activity android:name="com.packagename.ToActivity"></activity> 

Replace the below line code:

import android.view.View.OnClickListener; public class MainActivity extends Activity implements OnClickListener{  Button button; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main);  button=(Button)findViewById(R.id.button1); button.setOnClickListener(this); } public void onClick(View v) {   if(v.getId==R.id.button1){   Intent i = new Intent(FromActivity.this, ToActivity.class);   startActivity(i);   }  } } 

Add the below lines in your manifest file:

 <activity android:name="com.packagename.FromActivity"></activity> <activity android:name="com.packagename.ToActivity"></activity> 

Replace the below line code:

import android.view.View.OnClickListener; public class MainActivity extends Activity implements OnClickListener{ 

Place the below method in your MainActivity.java

 public void onClick(View v) { if(v.getId==R.id.button1){ Intent i = new Intent(FromActivity.this, ToActivity.class); startActivity(i); } } 

Add the blow lines in your manifest file:

 <activity android:name="com.packagename.FromActivity"></activity> <activity android:name="com.packagename.ToActivity"></activity> 

Replace the below line code:

import android.view.View.OnClickListener; public class MainActivity extends Activity implements OnClickListener{ 

Place the below method in your MainActivity.java

 public void onClick(View v) { if(v.getId==R.id.button1){ Intent i = new Intent(FromActivity.this, ToActivity.class); startActivity(i); } } 

Add the below lines in your manifest file:

 <activity android:name="com.packagename.FromActivity"></activity> <activity android:name="com.packagename.ToActivity"></activity>