简单 二维码 生成以及识别
1. 二维码
本质：生成过程是将字符串转换为图形
识别：扫描图形转换为字符串
首先需要依赖lib_QRCode库（在附件中可以下载）
1.在代码中设置
package com.example.ex_templete;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ImageView;
import android.widget.Toast;
import com.ericssonlabs.BarCodeTestActivity;
import com.google.zxing.WriterException;
import com.zxing.activity.CaptureActivity;
import com.zxing.encoding.EncodingHandler;
public class MainActivity extends Activity {
private ImageView mImageView;
public void scan(View v) {
//打开扫描界面扫描条形码或二维码
Intent openCameraIntent = new Intent(this, CaptureActivity.class);
startActivityForResult(openCameraIntent, 0);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
//处理扫描结果（在界面上显示）
if (resultCode == RESULT_OK) {
Bundle bundle = data.getExtras();
String scanResult = bundle.getString("result");
//resultTextView.setText(scanResult);
}
}
public void onClick(View v) {
try {
String contentString = "http://www.baidu.com";
if (contentString != null && contentString.trim().length() > 0) {
// 根据字符串生成二维码图片并显示在界面上，第二个参数为图片的大小（350*350）
Bitmap qrCodeBitmap = EncodingHandler.createQRCode(
contentString, 350);
mImageView.setImageBitmap(qrCodeBitmap);
} else {
Toast.makeText(this, "Text can not be empty",
Toast.LENGTH_SHORT).show();
}
} catch (WriterException e) {
e.printStackTrace();
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mImageView = (ImageView) findViewById(R.id.imageView1);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
2.xml中
<RelativeLayout 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:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.ex_templete.MainActivity" >
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:onClick="onClick"
android:text="生成二维码" />
<ImageView
android:id="@+id/imageView1"
android:layout_width="230dp"
android:layout_height="230dp"
android:scaleType="fitXY"
android:layout_alignLeft="@+id/button1"
android:layout_below="@+id/button1"
android:layout_marginTop="24dp"
android:src="@drawable/ic_launcher" />
<Button
android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBottom="@+id/button1"
android:layout_alignParentRight="true"
android:layout_marginRight="30dp"
android:onClick="scan"
android:text="扫一扫" />
</RelativeLayout>
3.在文档中配置权限以及注册activity
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.xinbo.demo"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="18" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />
<uses-permission android:name="android.permission.VIBRATE" />
<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" />
<uses-feature android:name="android.hardware.camera.autofocus" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.xinbo.demo.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<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>
</application>
</manifest>