Android怎样实现扫描和生成二维码

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:tools="http://schemas.android.com/tools"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:orientation="vertical"
 tools:context=".MainActivity" >
 
 <Button
 android:id="@+id/btScan"
 android:layout_width="fill_parent"
 android:layout_height="wrap_content"
 android:text="开始扫描二维码" />
 
 <TextView
 android:id="@+id/tvShow"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:layout_marginTop="20dp"
 android:text="二维码结果：" />
 
 <EditText
 android:id="@+id/etInput"
 android:layout_width="fill_parent"
 android:layout_height="wrap_content"
 android:layout_marginTop="50dp"
 android:hint="请输入要编码的内容">
 
 
 </EditText>
 
 <Button
 android:id="@+id/btGet"
 android:layout_width="fill_parent"
 android:layout_height="wrap_content"
 android:text="生成二维码" />
 
 <ImageView 
 android:id="@+id/ivCode"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:layout_gravity="center_horizontal"/>
 
</LinearLayout>

package com.example.testqrcode;
 
import com.google.zxing.WriterException;
import com.zxing.activity.CaptureActivity;
import com.zxing.encoding.EncodingHandler;
 
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
 
public class MainActivity extends Activity {
 private Button btScan, btGet;
 private TextView tvShow;
 private ImageView ivCode;
 private EditText etInput;
 
 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_main);
 
 btScan = (Button) findViewById(R.id.btScan);
 tvShow = (TextView) findViewById(R.id.tvShow);
 btGet = (Button) findViewById(R.id.btGet);
 ivCode = (ImageView) findViewById(R.id.ivCode);
 etInput = (EditText) findViewById(R.id.etInput);
 
 // 扫描二维码
 btScan.setOnClickListener(new OnClickListener() {
 
 @Override
 public void onClick(View arg0) {
 Toast.makeText(MainActivity.this, "你可以扫描条形码或者二维码",
 Toast.LENGTH_SHORT).show();
 Intent intent = new Intent(MainActivity.this,
 CaptureActivity.class);
 // startActivity(intent); //不能回传数据的跳转方式
 startActivityForResult(intent, 0); // 能获取回传数据的跳转方式
 }
 });
 
 // 生成二维码
 btGet.setOnClickListener(new OnClickListener() {
 
 @Override
 public void onClick(View arg0) {
 String in = etInput.getText().toString();
 if (in.equals("")) {
 Toast.makeText(MainActivity.this, "请输入文本",
 Toast.LENGTH_SHORT).show();
 } else {
 try {
 
 Bitmap qrcode = EncodingHandler.createQRCode(in, 400);
 ivCode.setImageBitmap(qrcode);
 } catch (WriterException e) {
 // TODO Auto-generated catch block
 e.printStackTrace();
 }// 第一个参数是想要生成的文本，第二个参数是生成二维码横向和纵向的宽度
 }
 }
 });
 }
 
 // 接收扫描的activity传回来的值
 @Override
 protected void onActivityResult(int requestCode, int resultCode, Intent data) {
 super.onActivityResult(requestCode, resultCode, data);
 if (resultCode == RESULT_OK) {
 String result = data.getExtras().getString("result");
 tvShow.setText(result);
 }
 }
 
}

<uses-permission android:name="android.permission.CAMERA"/>
 <uses-permission android:name="android.permission.VIBRATE"/>

<activity
 android:name="com.zxing.activity.CaptureActivity"
 android:configChanges="orientation|keyboardHidden"
 android:screenOrientation="portrait"
 android:theme="@android:style/Theme.NoTitleBar.Fullscreen"
 android:windowSoftInputMode="stateAlwaysHidden" >
</activity>