如何在 android 中获得相机许可。（特别是 Marshmallow）

Question

嘿，我正在 android 工作室设计一个应用程序。其中我需要相机的许可。我已将 <uses-permission android:name="android.permission.CAMERA" /> 包含在 AndroidManifest.xml 文件中。它在除 Marshmallow 之外的所有 android 版本中都可以正常工作。默认情况下如何获得相机权限？如果不可能，我该如何向用户询问？

Answer 1

首先检查用户是否授权：

if (ContextCompat.checkSelfPermission(context, Manifest.permission.CAMERA)
    == PackageManager.PERMISSION_DENIED)

然后，您可以使用它向用户请求：

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

而在 Marshmallow 中，它将出现在对话框中

Answer 2

check using this
if (ContextCompat.checkSelfPermission(this, android.Manifest.permission.CAMERA)
            == PackageManager.PERMISSION_DENIED)

和

Answer 3

您可以尝试使用以下代码在棉花糖中请求相机权限。首先检查用户是否授予权限。如果用户没有授权，则请求摄像头权限：

private static final int MY_CAMERA_REQUEST_CODE = 100;

if (checkSelfPermission(Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
    requestPermissions(new String[]{Manifest.permission.CAMERA}, MY_CAMERA_REQUEST_CODE);
}

请求权限后，将显示包含 allow 和 deny 选项的请求权限对话框。单击操作后，我们可以使用以下方法获取请求结果：

@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    if (requestCode == MY_CAMERA_REQUEST_CODE) {
        if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
            Toast.makeText(this, "camera permission granted", Toast.LENGTH_LONG).show();
        } else {
            Toast.makeText(this, "camera permission denied", Toast.LENGTH_LONG).show();
        }
    }
}

Answer 4

这对我有用，来源是 here

int MY_PERMISSIONS_REQUEST_CAMERA=0;
// Here, this is the current activity
if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED)
{
     if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.CAMERA))
     {

     }
     else
     {
          ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.CAMERA}, MY_PERMISSIONS_REQUEST_CAMERA );
          // MY_PERMISSIONS_REQUEST_READ_CONTACTS is an
          // app-defined int constant. The callback method gets the
          // result of the request.
      }
}

Answer 5

请求权限在下面的代码中，我们将请求相机权限：

在java

EasyPermissions 是一个包装库，用于在目标 Android M 或更高时简化基本系统权限逻辑。

安装通过将以下依赖项添加到 build.gradle 文件来安装 EasyPermissions：

dependencies {

    // For developers using AndroidX in their applications
    implementation 'pub.devrel:easypermissions:3.0.0'

    // For developers using the Android Support Library
    implementation 'pub.devrel:easypermissions:2.0.1'

}


private void askAboutCamera(){

        EasyPermissions.requestPermissions(
                this,
                "A partir deste ponto a permissão de câmera é necessária.",
                CAMERA_REQUEST_CODE,
                Manifest.permission.CAMERA );
}

Answer 6

click here 获取完整源代码并了解更多信息。

在获得权限之前你可以检查api版本，

  if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M)
  {
      if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED) {

      } 
      else
      {
         ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, 401);
      }
  }
  else
  {
    // if version is below m then write code here,          
  }

获取权限对话框的结果，

@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    if (requestCode == 401) {
        if (grantResults.length == 0 || grantResults == null) {

        } else if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
            openGallery();
        } else if (grantResults[0] == PackageManager.PERMISSION_DENIED) {
        }
    } else if (requestCode == 402) {
        if (grantResults.length == 0 || grantResults == null) {

        } else if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {

        } else if (grantResults[0] == PackageManager.PERMISSION_DENIED) {
        }
    }
}

Answer 7

我尝试添加以下代码：

private static final int MY_CAMERA_REQUEST_CODE = 100;

@RequiresApi(api = Build.VERSION_CODES.M)

if (checkSelfPermission(Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
        requestPermissions(new String[]{Manifest.permission.CAMERA}, MY_CAMERA_REQUEST_CODE);
    }

onCreate 函数和以下代码：

@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    if (requestCode == MY_CAMERA_REQUEST_CODE) {
        if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
            Toast.makeText(this, "camera permission granted", Toast.LENGTH_LONG).show();
        } else {
            Toast.makeText(this, "camera permission denied", Toast.LENGTH_LONG).show();
        }
    }
}

这对我有用:)

Answer 8

         private const val CAMERA_PERMISSION_REQUEST_CODE = 2323

         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) 
           {
             if (checkSelfPermission(Manifest.permission.CAMERA) != 
             PackageManager.PERMISSION_GRANTED) 
               {
            requestPermissions(arrayOf(Manifest.permission.CAMERA), 
            CAMERA_PERMISSION_REQUEST_CODE)
               }
           }

Answer 9

获得许可的最简单方法之一是使用 deterex 库。像下面在 gradle.

中实现以下库

    implementation 'com.karumi:dexter:6.2.2'

添加库后使用此权限如下

        Dexter.withContext(this)
            .withPermissions(
                    Manifest.permission.CAMERA
            ).withListener(new MultiplePermissionsListener() {
        @Override public void onPermissionsChecked(MultiplePermissionsReport report) {/* ... */}
        @Override public void onPermissionRationaleShouldBeShown(List<PermissionRequest> permissions, PermissionToken token) {/*
        ... */}
    }).check();

不要忘记在清单中添加用户权限

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

如何在 android 中获得相机许可。（特别是 Marshmallow）

How get permission for camera in android.(Specifically Marshmallow)

camera

android