小编Sob*_*obo的帖子

我正在尝试创建一个将读取QR码的应用程序,此代码间歇性地工作,但它会给出权限错误,并且不会加载.我相信我已经修好了,但现在我得到了黑屏.没有错误,所以我不知道在哪里看,但我觉得它与权限有关.

package com.sample.qrcodereadervision.Activity;

import com.google.android.gms.vision.CameraSource;
import com.google.android.gms.vision.Detector;
import com.google.android.gms.vision.barcode.Barcode;
import com.google.android.gms.vision.barcode.BarcodeDetector;

import com.sample.qrcodereadervision.R;

import android.Manifest;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.design.widget.Snackbar;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.util.SparseArray;
import android.view.SurfaceView;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;

import java.io.IOException;

import permissions.dispatcher.NeedsPermission;
import permissions.dispatcher.OnPermissionDenied;
import permissions.dispatcher.OnShowRationale;
import permissions.dispatcher.PermissionRequest;
import permissions.dispatcher.PermissionUtils;
import permissions.dispatcher.RuntimePermissions;

@RuntimePermissions
public class QRcodeReader extends AppCompatActivity {
    public final String TAG = getClass().getSimpleName();

    private CameraSource cameraSource;
    /** UI Parts : Preview screen */
    private SurfaceView …