Google Android - это несложно

Код: Выделить всё

public class MainActivity extends Activity implements OnClickListener {

	TextView txt; 

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

public void onClick(View v) {
		 switch (v.getId()) {
	        case R.id.imageButton1:                
	        	txt.setText("5");
	          break;
	        case R.id.imageButton2:
	          
	        break;
	        }
	};    
}
}

Код: Выделить всё

public class MainActivity extends Activity implements OnClickListener {

 	EditText txtname;

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);               
                   
        txtname =(EditText) findViewById(R.id.editText2);

public void onClick(View v) {
		 switch (v.getId()) {
	        case R.id.imageButton1:                
	        	 txtname.setText("привет");	        	  	    		
	          break;
	        case R.id.imageButton2:
	                 ....
	        break;
	        }
		
	};    
	
	}