二维码的扫描

=======================activity_main布局===================

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/container"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.jikexueyuan.testqrcode.MainActivity"
    tools:ignore="MergeRootFrame" >


    <Button
        android:id="@+id/scan"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="开始扫描二维码" />
    <TextView 
        android:id="@+id/text"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="show"
        />
   <EditText 
       android:id="@+id/input"
       android:layout_width="fill_parent"
       android:layout_height="wrap_content"
       android:hint="请输入要编码的内容"
       />
   <Button 
       android:id="@+id/gen"
       android:layout_width="fill_parent"
       android:layout_height="wrap_content"
       android:text="生成二维码"
       />
   <ImageView 
       android:id="@+id/img"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:layout_gravity="center_horizontal"
       />


</LinearLayout>

=================MainActivity======================

package com.hf.barcode;


import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;


import com.google.zxing.WriterException;
import com.zxing.activity.CaptureActivity;
import com.zxing.encoding.EncodingHandler;


public class MainActivity extends Activity {

private Button scanButton;
private TextView text;
private EditText input;
private Button genButton;
private ImageView img;


@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
scanButton = (Button) findViewById(R.id.scan);
text = (TextView) findViewById(R.id.text);
scanButton.setOnClickListener(new View.OnClickListener() {

@Override
public void onClick(View arg0) {
Toast.makeText(MainActivity.this, "你写可以扫描条形码或者二维码", Toast.LENGTH_SHORT).show();
Intent  startScan = new Intent(MainActivity.this, CaptureActivity.class);
// startActivity(startScan);
startActivityForResult(startScan, 0);
}
});

input = (EditText) findViewById(R.id.input);
genButton = (Button) findViewById(R.id.gen);
img = (ImageView) findViewById(R.id.img);
genButton.setOnClickListener(new View.OnClickListener() {

@Override
public void onClick(View arg0) {
String in = input.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);
img.setImageBitmap(qrcode);
} catch (WriterException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}


}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// TODO Auto-generated method stub
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK) {
String result = data.getExtras().getString("result");
text.setText(result);
}
}
}

=======================关联一个类库，叫BarCodeTest，从极客学院下载的==