在Android项目中添加一个商品预订功能

package siso.calendarselector;import android.app.Activity;import android.content.Intent;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.view.View;import android.widget.EditText;import siso.calendarselector.lib.CalendarSelectorActivity;public class MainActivity extends Activity { private EditText orderEt; @Override protected void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.activity_main); } public void jump(View v) {  EditText et = (EditText) findViewById(R.id.et_input);  orderEt = (EditText) findViewById(R.id.et_order);  int days = Integer.valueOf(et.getText().toString());  String order = orderEt.getText().toString();  Intent i = new Intent(MainActivity.this, CalendarSelectorActivity.class);  i.putExtra(CalendarSelectorActivity.DAYS_OF_SELECT, days);  i.putExtra(CalendarSelectorActivity.ORDER_DAY, order);  startActivityForResult(i, 1); } @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) {  super.onActivityResult(requestCode, resultCode, data);  if (requestCode == 1 && resultCode == RESULT_OK) {   String orderInfo = data.getStringExtra(CalendarSelectorActivity.ORDER_DAY);   orderEt.setText(orderInfo);     } }}