Why point BUTTON Button program suddenly shut down?

Activity Android Intent

This is the first Main.java

 package com.example.task2; 

import android.content.Intent; 
import android.app.Activity; 
import android.os.Bundle; 
import android.util.Log; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.widget.Button; 
import android.widget.TextView; 

public class Main extends Activity {

private static final String TAG = "Main"; 
protected TextView editText1; 
@ Override 
protected void onCreate (Bundle savedInstanceState) {
super.onCreate (savedInstanceState); 
setContentView (R.layout.main); 
Log.v (TAG, "onCreate"); 

Button button1 = (Button) findViewById (R.id.button1); 

button1.setOnClickListener (new OnClickListener () {
public void onClick (View v) 
{
String a = editText1.getText () toString ();. 
Bundle bundle = new Bundle (); 
Intent intent = new Intent (); 
bundle.putString ("a", a); 
intent.putExtras (bundle); 
intent.setClass (Main.this, OtherActivity.class); 

startActivity (intent); 
} 

}); 

} 

} 

This is the second OtherActivity.java

 package com.example.task2; 

import android.os.Bundle; 
import android.app.Activity; 
import android.content.Intent; 
import android.view.View; 
import android.widget.Button; 
import android.widget.TextView; 
import android.util.Log; 

public class OtherActivity extends Activity {

private static final String TAG = "OtherActivity"; 
private TextView textView; 
public void onCreate (Bundle savedInstanceState) 
{
super.onCreate (savedInstanceState); 
setContentView (R.layout.other); 
Log.v (TAG, "onCreate"); 

Intent intent = getIntent (); 
Bundle bundle = intent.getExtras (); 
String str = bundle.getString ("a"); 
textView = (TextView) findViewById (R.id.three); 
textView.setText (str); 

Button button = (Button) findViewById (R.id.button2); 
button.setOnClickListener (new Button.OnClickListener () 
{

@ Override 
public void onClick (View v) {
/ / TODO Auto-generated method stub 
Intent intent = new Intent (); 
intent.setClass (OtherActivity.this, Main.class); 
startActivity (intent); 

} 

}); 

} 

} 

xml file is correct<-! Main posts under Banner (D4) -><-! Posts under the main text (D5) ->
Reply:
The first class editText1 the landlord has no value, and see what you mean type should be EditText, rather than TextView

 private EditText editText1; 

final EditText editText1 = (EditText) findViewById (R.id.editText1); 

Reply:
To correct:

 private EditText editText1; 
editText1 = (EditText) findViewById (R.id.editText1); 

Reply:

reference to the second floor ncepu307 reply:

to correct:

 private EditText editText1; 
editText1 = (EditText) findViewById (R.id.editText1); 

Thank you very much, did not tune out tune for a long time, and now finally the way, thank you