易采站长站为您分析Android基于google Zxing实现二维码的生成的相关资料,需要的朋友可以参考下
最近项目用到了二维码的生成与识别,之前没有接触这块,然后就上网搜了搜,发现有好多这方面的资源,特别是google Zxing对二维码的封装,实现的已经不错了,可以直接拿过来引用,下载了他们的源码后,只做了少少的改动,就是在Demo中增加了长按识别的功能,网上虽然也有长按识别的Demo,但好多下载下来却无法运行,然后总结了一下,加在了下面的Demo中。
下面来介绍这个Demo的主类
public class BarCodeTestActivity extends Activity {
private TextView resultTextView;
private EditText qrStrEditText;
private ImageView qrImgImageView;
private String time;
private File file = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
resultTextView = (TextView) this.findViewById(R.id.tv_scan_result);
qrStrEditText = (EditText) this.findViewById(R.id.et_qr_string);
qrImgImageView = (ImageView) this.findViewById(R.id.iv_qr_image);
Button scanBarCodeButton = (Button) this.findViewById(R.id.btn_scan_barcode);
scanBarCodeButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
//打开扫描界面扫描条形码或二维码
Intent openCameraIntent = new Intent(BarCodeTestActivity.this,CaptureActivity.class);
startActivityForResult(openCameraIntent, 0);
}
});
qrImgImageView.setOnLongClickListener(new OnLongClickListener() {
@Override
public boolean onLongClick(View v) {
// 长按识别二维码
saveCurrentImage();
return true;
}
});
Button generateQRCodeButton = (Button) this.findViewById(R.id.btn_add_qrcode);
generateQRCodeButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
try {
String contentString = qrStrEditText.getText().toString();
if (!contentString.equals("")) {
//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);
qrImgImageView.setImageBitmap(qrCodeBitmap);
}else {
//提示文本不能是空的
Toast.makeText(BarCodeTestActivity.this, "Text can not be empty", Toast.LENGTH_SHORT).show();
}
} catch (WriterException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
}
//这种方法状态栏是空白,显示不了状态栏的信息
private void saveCurrentImage()
{
//获取当前屏幕的大小
int width = getWindow().getDecorView().getRootView().getWidth();
int height = getWindow().getDecorView().getRootView().getHeight();
//生成相同大小的图片
Bitmap temBitmap = Bitmap.createBitmap( width, height, Bitmap.Config.ARGB_8888 );
//找到当前页面的根布局
View view = getWindow().getDecorView().getRootView();
//设置缓存
view.setDrawingCacheEnabled(true);
view.buildDrawingCache();
//从缓存中获取当前屏幕的图片,创建一个DrawingCache的拷贝,因为DrawingCache得到的位图在禁用后会被回收
temBitmap = view.getDrawingCache();
SimpleDateFormat df = new SimpleDateFormat("yyyymmddhhmmss");
time = df.format(new Date());
if(Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState())){
file = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + "/screen",time + ".png");
if(!file.exists()){
file.getParentFile().mkdirs();
try {
file.createNewFile();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
FileOutputStream fos = null;
try {
fos = new FileOutputStream(file);
temBitmap.compress(Bitmap.CompressFormat.PNG, 100, fos);
fos.flush();
fos.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
new Thread(new Runnable() {
@Override
public void run() {
String path = Environment.getExternalStorageDirectory().getAbsolutePath() + "/screen/" + time + ".png";
final Result result = parseQRcodeBitmap(path);
runOnUiThread(new Runnable() {
public void run() {
if(null!=result){
resultTextView.setText(result.toString());
}else{
Toast.makeText(BarCodeTestActivity.this, "无法识别", Toast.LENGTH_LONG).show();
}
}
});
}
}).start();
//禁用DrawingCahce否则会影响性能 ,而且不禁止会导致每次截图到保存的是缓存的位图
view.setDrawingCacheEnabled(false);
}
}
//解析二维码图片,返回结果封装在Result对象中
private com.google.zxing.Result parseQRcodeBitmap(String bitmapPath){
//解析转换类型UTF-8
Hashtable<DecodeHintType, String> hints = new Hashtable<DecodeHintType, String>();
hints.put(DecodeHintType.CHARACTER_SET, "utf-8");
//获取到待解析的图片
BitmapFactory.Options options = new BitmapFactory.Options();
//如果我们把inJustDecodeBounds设为true,那么BitmapFactory.decodeFile(String path, Options opt)
//并不会真的返回一个Bitmap给你,它仅仅会把它的宽,高取回来给你
options.inJustDecodeBounds = true;
//此时的bitmap是null,这段代码之后,options.outWidth 和 options.outHeight就是我们想要的宽和高了
Bitmap bitmap = BitmapFactory.decodeFile(bitmapPath,options);
//我们现在想取出来的图片的边长(二维码图片是正方形的)设置为400像素
/**
options.outHeight = 400;
options.outWidth = 400;
options.inJustDecodeBounds = false;
bitmap = BitmapFactory.decodeFile(bitmapPath, options);
*/
//以上这种做法,虽然把bitmap限定到了我们要的大小,但是并没有节约内存,如果要节约内存,我们还需要使用inSimpleSize这个属性
options.inSampleSize = options.outHeight / 400;
if(options.inSampleSize <= 0){
options.inSampleSize = 1; //防止其值小于或等于0
}
/**
* 辅助节约内存设置
*
* options.inPreferredConfig = Bitmap.Config.ARGB_4444; // 默认是Bitmap.Config.ARGB_8888
* options.inPurgeable = true;
* options.inInputShareable = true;
*/
options.inJustDecodeBounds = false;
bitmap = BitmapFactory.decodeFile(bitmapPath, options);
//新建一个RGBLuminanceSource对象,将bitmap图片传给此对象
RGBLuminanceSource rgbLuminanceSource = new RGBLuminanceSource(bitmap);
//将图片转换成二进制图片
BinaryBitmap binaryBitmap = new BinaryBitmap(new HybridBinarizer(rgbLuminanceSource));
//初始化解析对象
QRCodeReader reader = new QRCodeReader();
//开始解析
Result result = null;
try {
result = reader.decode(binaryBitmap, hints);
} catch (Exception e) {
// TODO: handle exception
}
return result;
}
@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);
}
}
}










