Android,如何在我的应用程序中阅读QR码？

Question

在我的应用程序中,我需要阅读Qr代码.我在网上搜索并找到了Zing代码但是很多开发人员使用它时遇到了问题,而且它似乎有问题!

如果我假设我的客户在他们的设备上安装了qr阅读器,我如何使用这些应用程序并通过隐式意图调用它们？

如果用户没有任何qr阅读器,应用程序会发生什么？如果它崩溃,我可以要求用户下载例如QrDroid,然后使用它吗？

Answer 1

try {

    Intent intent = new Intent("com.google.zxing.client.android.SCAN");
    intent.putExtra("SCAN_MODE", "QR_CODE_MODE"); // "PRODUCT_MODE for bar codes

    startActivityForResult(intent, 0);

} catch (Exception e) {

    Uri marketUri = Uri.parse("market://details?id=com.google.zxing.client.android");
    Intent marketIntent = new Intent(Intent.ACTION_VIEW,marketUri);
    startActivity(marketIntent);

}

并在 onActivityResult():

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {           
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == 0) {

        if (resultCode == RESULT_OK) {
            String contents = data.getStringExtra("SCAN_RESULT");
        }
        if(resultCode == RESULT_CANCELED){
            //handle cancel
        }
    }
}

Answer 2

Zxing是执行Qr代码扫描和生成的优秀库.以下实现使用Zxing库扫描QR代码图像不要忘记在build.gradle中添加以下依赖项

compile 'me.dm7.barcodescanner:zxing:1.9'

代码扫描器活动:

public class QrCodeScanner extends AppCompatActivity implements ZXingScannerView.ResultHandler {
    private ZXingScannerView mScannerView;

    @Override
    public void onCreate(Bundle state) {
        super.onCreate(state);
        // Programmatically initialize the scanner view
        mScannerView = new ZXingScannerView(this);
        // Set the scanner view as the content view
        setContentView(mScannerView);
    }

    @Override
    public void onResume() {
        super.onResume();
        // Register ourselves as a handler for scan results.
        mScannerView.setResultHandler(this);
        // Start camera on resume
        mScannerView.startCamera();
    }

    @Override
    public void onPause() {
        super.onPause();
        // Stop camera on pause
        mScannerView.stopCamera();
    }

    @Override
    public void handleResult(Result rawResult) {
        // Do something with the result here
        // Prints scan results
        Logger.verbose("result", rawResult.getText());
        // Prints the scan format (qrcode, pdf417 etc.)
        Logger.verbose("result", rawResult.getBarcodeFormat().toString());
        //If you would like to resume scanning, call this method below:
        //mScannerView.resumeCameraPreview(this);
        Intent intent = new Intent();
        intent.putExtra(AppConstants.KEY_QR_CODE, rawResult.getText());
        setResult(RESULT_OK, intent);
        finish();
    }
}

Answer 3

如果用户没有任何qr阅读器,应用程序会发生什么？如果它崩溃,我可以要求用户下载例如QrDroid,然后使用它吗？

有趣的是,Google现在推出了Mobile Vision API,它们本身也集成在游戏服务中.

在Gradle文件中,只需添加:

compile 'com.google.android.gms:play-services-vision:11.4.0'

摘自此QR码教程.

Answer 4

在android studio中,你可以使用下面的流程创建和读取QR码 和图像看起来像bellw

1. 创建一个android studio空项目

2. 在app.gradle中添加库

   compile 'com.google.zxing:core:3.2.1'
   compile 'com.journeyapps:zxing-android-embedded:3.2.0@aar'
   

3. 在activity.main xml中使用以下..

    <?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.enamul.qrcode.MainActivity">
   
   <LinearLayout
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:layout_margin="20dp"
     android:orientation="vertical">
   
   
   <EditText
       android:id="@+id/editText"
       android:layout_width="fill_parent"
       android:layout_height="wrap_content"
       android:gravity="center"
       android:hint="Enter Text Here" />
   
   <Button
       android:id="@+id/button"
       android:layout_width="fill_parent"
       android:layout_height="50dp"
       android:layout_below="@+id/editText"
       android:text="Click Here TO generate qr code"
       android:textAllCaps="false"
       android:textSize="16sp" />
   
   
   <Button
       android:id="@+id/btnScan"
       android:layout_width="fill_parent"
       android:layout_height="50dp"
       android:layout_below="@+id/editText"
       android:text="Scan Your QR Code"
       android:textAllCaps="false"
       android:textSize="16sp" />
   
   <TextView
       android:id="@+id/tv_qr_readTxt"
       android:layout_width="match_parent"
       android:layout_height="wrap_content" />
   
   
   <ImageView
       android:id="@+id/imageView"
       android:layout_width="match_parent"
       android:layout_height="200dp"
       android:layout_below="@+id/button"
       android:src="@android:drawable/ic_dialog_email" />
   
   
   </LinearLayout>
   
   </LinearLayout>
   

4. 在MainActivity中,您可以使用以下代码

   public class MainActivity extends AppCompatActivity {
     ImageView imageView;
     Button button;
     Button btnScan;
     EditText editText;
     String EditTextValue ;
     Thread thread ;
     public final static int QRcodeWidth = 350 ;
     Bitmap bitmap ;
   
     TextView tv_qr_readTxt;
   
    @Override
    protected void onCreate(Bundle savedInstanceState) {
     super.onCreate(savedInstanceState);
     setContentView(R.layout.activity_main);
   
       imageView = (ImageView)findViewById(R.id.imageView);
       editText = (EditText)findViewById(R.id.editText);
       button = (Button)findViewById(R.id.button);
       btnScan = (Button)findViewById(R.id.btnScan);
        tv_qr_readTxt = (TextView) findViewById(R.id.tv_qr_readTxt);
   
   button.setOnClickListener(new View.OnClickListener() {
       @Override
       public void onClick(View view) {
   
   
   
           if(!editText.getText().toString().isEmpty()){
               EditTextValue = editText.getText().toString();
   
               try {
                   bitmap = TextToImageEncode(EditTextValue);
   
                   imageView.setImageBitmap(bitmap);
   
               } catch (WriterException e) {
                   e.printStackTrace();
               }
           }
           else{
               editText.requestFocus();
               Toast.makeText(MainActivity.this, "Please Enter Your Scanned Test" , Toast.LENGTH_LONG).show();
           }
   
         }
     });
   
   
   btnScan.setOnClickListener(new View.OnClickListener() {
       @Override
       public void onClick(View view) {
   
           IntentIntegrator integrator = new IntentIntegrator(MainActivity.this);
           integrator.setDesiredBarcodeFormats(IntentIntegrator.ALL_CODE_TYPES);
           integrator.setPrompt("Scan");
           integrator.setCameraId(0);
           integrator.setBeepEnabled(false);
           integrator.setBarcodeImageEnabled(false);
           integrator.initiateScan();
   
        }
      });
       }
   
   
    Bitmap TextToImageEncode(String Value) throws WriterException {
      BitMatrix bitMatrix;
       try {
       bitMatrix = new MultiFormatWriter().encode(
               Value,
               BarcodeFormat.DATA_MATRIX.QR_CODE,
               QRcodeWidth, QRcodeWidth, null
       );
   
       } catch (IllegalArgumentException Illegalargumentexception) {
   
        return null;
      }
     int bitMatrixWidth = bitMatrix.getWidth();
   
     int bitMatrixHeight = bitMatrix.getHeight();
   
     int[] pixels = new int[bitMatrixWidth * bitMatrixHeight];
   
     for (int y = 0; y < bitMatrixHeight; y++) {
         int offset = y * bitMatrixWidth;
   
        for (int x = 0; x < bitMatrixWidth; x++) {
   
            pixels[offset + x] = bitMatrix.get(x, y) ?
                   getResources().getColor(R.color.QRCodeBlackColor):getResources().getColor(R.color.QRCodeWhiteColor);
         }
       }
       Bitmap bitmap = Bitmap.createBitmap(bitMatrixWidth, bitMatrixHeight, Bitmap.Config.ARGB_4444);
   
      bitmap.setPixels(pixels, 0, 350, 0, 0, bitMatrixWidth, bitMatrixHeight);
      return bitmap;
   }
   
   
   
   
     @Override
     protected void onActivityResult(int requestCode, int resultCode, Intent data) {
       IntentResult result = IntentIntegrator.parseActivityResult(requestCode, resultCode, data);
     if(result != null) {
       if(result.getContents() == null) {
           Log.e("Scan*******", "Cancelled scan");
   
        } else {
           Log.e("Scan", "Scanned");
   
           tv_qr_readTxt.setText(result.getContents());
           Toast.makeText(this, "Scanned: " + result.getContents(), Toast.LENGTH_LONG).show();
        }
     } else {
         // This is important, otherwise the result will not be passed to the fragment
       super.onActivityResult(requestCode, resultCode, data);
        }
      }
    }
   

5. 您可以从GitHub下载完整的源代码.GitHub链接是:https: //github.com/enamul95/QRCode

Answer 5

我已经创建了一个简单的示例教程.您可以阅读此内容并在您的应用程序中使用.

http://ribinsandroidhelper.blogspot.in/2013/03/qr-code-reading-on-your-application.html

通过此链接,您可以下载qrcode库项目并导入到工作区并将库添加到项目中

并将此代码复制到您的活动中

 Intent intent = new Intent("com.google.zxing.client.android.SCAN");
 startActivityForResult(intent, 0);

 public void onActivityResult(int requestCode, int resultCode, Intent intent) {
     if (requestCode == 0) {
         if (resultCode == RESULT_OK) {
             String contents = intent.getStringExtra("SCAN_RESULT");
             String format = intent.getStringExtra("SCAN_RESULT_FORMAT");
             Toast.makeText(this, contents,Toast.LENGTH_LONG).show();
             // Handle successful scan
         } else if (resultCode == RESULT_CANCELED) {
             //Handle cancel
         }
     }
}