Android 相机 QR 扫描仪的权限

Question

我正在创建一个 android 应用程序并想集成 ZXing QR Scanner。当我从一个 Intent 启动 QRScanner activity 时，我得到了祝酒词 "Permission Denied, You cannot access and camera" 并且应用程序冻结而不是请求相机许可。

对于如何正确实施权限请求或识别我查看过的任何错误的任何帮助，我们将不胜感激。

      public class Qrscanner extends AppCompatActivity implements 
      ZXingScannerView.ResultHandler {

    private static final int REQUEST_CAMERA = 1;
    private ZXingScannerView scannerView;
    private static int camId = Camera.CameraInfo.CAMERA_FACING_BACK;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        scannerView = new ZXingScannerView(this);
        setContentView(scannerView);
        int currentApiVersion = Build.VERSION.SDK_INT;

        if(currentApiVersion >=  Build.VERSION_CODES.M)
        {
            if(checkPermission())
            {
                Toast.makeText(getApplicationContext(), "Permission already granted!", Toast.LENGTH_LONG).show();
            }
            else
            {
                requestPermission();
            }
        }
    }

    private boolean checkPermission()
    {
        return (ContextCompat.checkSelfPermission(getApplicationContext(), CAMERA) == PackageManager.PERMISSION_GRANTED);
    }

    private void requestPermission()
    {
        ActivityCompat.requestPermissions(this, new String[]{CAMERA}, REQUEST_CAMERA);
    }

    @Override
    public void onResume() {
        super.onResume();

        int currentapiVersion = android.os.Build.VERSION.SDK_INT;
        if (currentapiVersion >= android.os.Build.VERSION_CODES.M) {
            if (checkPermission()) {
                if(scannerView == null) {
                    scannerView = new ZXingScannerView(this);
                    setContentView(scannerView);
                }
                scannerView.setResultHandler(this);
                scannerView.startCamera();
            } else {
                requestPermission();
            }
        }
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        scannerView.stopCamera();
    }

    public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
        final int req = requestCode;
        switch (requestCode) {

            case REQUEST_CAMERA:
                if (grantResults.length > 0) {

                    boolean cameraAccepted = grantResults[0] == PackageManager.PERMISSION_GRANTED;
                    if (cameraAccepted){
                        Toast.makeText(getApplicationContext(), "Permission Granted, Now you can access camera", Toast.LENGTH_LONG).show();
                    }else {
                        Toast.makeText(getApplicationContext(), "Permission Denied, You cannot access and camera", Toast.LENGTH_LONG).show();
                        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                            if (shouldShowRequestPermissionRationale(CAMERA)) {
                                showMessageOKCancel("You need to allow access to both the permissions",
                                        new DialogInterface.OnClickListener() {
                                            @Override
                                            public void onClick(DialogInterface dialog, int which) {
                                                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
  //                                                    
   requestPermissions(new String[]{CAMERA},
   //                                                            
   REQUEST_CAMERA);

    ActivityCompat.requestPermissions(getParent(), new String[] 
    {Manifest.permission.CAMERA}, req);

                                                }
                                            }
                                        });
                                return;
                            }
                        }
                    }
                }
                break;
        }
    }

    private void showMessageOKCancel(String message, DialogInterface.OnClickListener okListener) {
        new android.support.v7.app.AlertDialog.Builder(Qrscanner.this)
                .setMessage(message)
                .setPositiveButton("OK", okListener)
                .setNegativeButton("Cancel", null)
                .create()
                .show();
    }

    @Override
    public void handleResult(final Result result) {
        final String myResult = result.getText();
        Log.d("QRCodeScanner", result.getText());
        Log.d("QRCodeScanner", result.getBarcodeFormat().toString());

        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle("Scan Result");
        builder.setPositiveButton("Try Again", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                scannerView.resumeCameraPreview(Qrscanner.this);
            }
        });
        builder.setNeutralButton("Confirm", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
               Intent intent = new Intent(getApplicationContext(),AddKeys.class);
               intent.putExtra("publicKey",result.getText());
               startActivity(intent);
            }
        });
        builder.setMessage(result.getText());
        AlertDialog alert1 = builder.create();
        alert1.show();
    }
}

Answer 1

您的问题有一个非常简单的解决方案。在 onCreate 里面提供运行时权限。我建议您使用 dexter 库，因为它是实现运行时权限的最简单方法。这是图书馆的 link： https://github.com/Karumi/Dexter

Answer 2

首先你需要给你的AndroidManifest.xml添加相机权限:

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

然后您需要在运行时要求用户使用以下方式启用此权限：

activity.requestPermissions(new String[]{Manifest.permission.CAMERA}, 1011);

然后重写权限对话框结果后调用的方法：

    @Override
    public void onRequestPermissionsResult(int requestCode,
                                   String permissions[], int[] grantResults) {
    switch (requestCode) {
        case 1011: {

      // If request is cancelled, the result arrays are empty.
            if (grantResults.length > 0
                && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

            // Here user granted the permission     
            } else {

            // permission denied, boo! Disable the
            // functionality that depends on this permission.
                Toast.makeText(MainActivity.this, "Permission denied to read your Camera", Toast.LENGTH_SHORT).show();
            }
            return;
         }
       }
    }

Answer 3

构建您的 cameSource 后，我遇到了同样的问题。将此行添加到您的代码中，它适用于我

final String[] permissions = new String[] Manifest.permission.CAMERA};

if (!ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this, Manifest.permission.CAMERA)) {
    ActivityCompat.requestPermissions(MainActivity.this, permissions, RC_HANDLE_CAMERA_PERM);
}

Android 相机 QR 扫描仪的权限

Permissions for Android Camera QR Scanner

java

android

qr-code

zxing

android-studio