Android 6撤销了已批准的权限

Question

有问题的帽子我不确定是不是一个bug.

如果用户授予权限然后撤消它,则checkSelfPermission似乎会对撤销的权限返回GRANTED.

例如,撤销许可后似乎.CAMERA:

true == ActivityCompat.checkSelfPermission(context, permission.CAMERA)
                            == PackageManager.PERMISSION_GRANTED

我似乎发现相机被撤销的唯一方法是例外:

10-20 14:25:54.330: E/AndroidRuntime(13954): java.lang.SecurityException: Permission Denial: starting Intent { act=android.media.action.IMAGE_CAPTURE flg=0x3 cmp=com.google.android.GoogleCamera/com.android.camera.CaptureActivity clip={text/uri-list U:file:///storage/emulated/0/Pictures/JPEG_20151020_142554_399504353.jpg} (has extras) } from ProcessRecord{adc5d77 13954:com.conx2share.conx2share.staging/u0a144} (pid=13954, uid=10144) with revoked permission android.permission.CAMERA
10-20 14:25:54.330: E/AndroidRuntime(13954):    at android.os.Parcel.readException(Parcel.java:1599)
10-20 14:25:54.330: E/AndroidRuntime(13954):    at android.os.Parcel.readException(Parcel.java:1552)
10-20 14:25:54.330: E/AndroidRuntime(13954):    at android.app.ActivityManagerProxy.startActivity(ActivityManagerNative.java:2658)
10-20 14:25:54.330: E/AndroidRuntime(13954):    at android.app.Instrumentation.execStartActivity(Instrumentation.java:1507)
10-20 14:25:54.330: E/AndroidRuntime(13954):    at android.app.Activity.startActivityForResult(Activity.java:3917)
10-20 14:25:54.330: E/AndroidRuntime(13954):    at android.app.Activity.startActivityForResult(Activity.java:3877)
10-20 14:25:54.330: E/AndroidRuntime(13954):    at android.support.v4.app.FragmentActivity.startActivityFromFragment(FragmentActivity.java:855)
10-20 14:25:54.330: E/AndroidRuntime(13954):    at android.support.v4.app.FragmentActivity$HostCallbacks.onStartActivityFromFragment(FragmentActivity.java:907)
10-20 14:25:54.330: E/AndroidRuntime(13954):    at android.support.v4.app.Fragment.startActivityForResult(Fragment.java:930)

有谁知道这是用户错误还是新权限系统中的错误？

Answer 1

我参加派对有点晚了,但我刚遇到这个问题并认为将来对其他人有用.

根据Google链接https://developers.google.com/android/guides/permissions#prerequisites

除了新的平台功能,Android 6.0 Marshmallow还有一个新的权限模型,可以简化应用安装和自动更新过程.现在,在运行时请求权限,而不是应用程序安装之前.

因此,如果您将应用程序定位到SDK级别23或更高级别,则AndroidManifest.xml中声明的权限是不够的(尽管必要).确保您使用的是V4支持库并进行检查,如下所示:

@Override
    public void onClick(View view) {

        // Check permission for CAMERA
        if (ActivityCompat.checkSelfPermission(context, Manifest.permission.CAMERA)
                != PackageManager.PERMISSION_GRANTED) {
            // Check Permissions Now
            // Callback onRequestPermissionsResult interceptado na Activity MainActivity
            ActivityCompat.requestPermissions(getActivity(),
                                              new String[]{Manifest.permission.CAMERA},
                                              MainActivity.REQUEST_CAMERA);
        } else {
            // permission has been granted, continue as usual

            Intent captureIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
            startActivityForResult(captureIntent, 0);
        }

在我的情况下,我做了检查Fragment,但可以在一个Activity,这取决于你的需要.

用户可以通过转到设置>应用> yourapp授予应用权限,然后授予权限.在这种情况下,逻辑顺序通过else并调用intent.另一方面,生活并不那么容易,用户也不会这样做.因此我们必须调用ActivityCompat.requestPermissions:

ActivityCompat.requestPermissions(getActivity(),
                                              new String[]{Manifest.permission.CAMERA},
                                              MainActivity.REQUEST_CAMERA);

在我传递的第一个参数中getActivity()因为我使用的是Fragment.如果您正在使用Activity,请通过this.第二个参数是要检查的权限,第三个参数是应用程序定义的int常量,用作回调方法的标识符,我将在下面解释.

public static final int REQUEST_CAMERA = 1;

ActivityCompat.requestPermissions将打开一个对话框,要求用户授予或拒绝该权限.这就是为什么我们必须使用这个方法onRequestPermissionsResult:

@Override
    public void onRequestPermissionsResult(int requestCode,
                                           String permissions[], int[] grantResults) {
        switch (requestCode) {
            case REQUEST_CAMERA: {
                // If request is cancelled, the result arrays are empty.
                if (grantResults.length > 0
                        && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

                    // permission was granted, yay! Do the
                    // contacts-related task you need to do.
                    Toast.makeText(getApplicationContext(), "Permission granted", Toast.LENGTH_SHORT).show();
                } else {

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

            // other 'case' lines to check for other
            // permissions this app might request
        }
    }

如果您正在使用Fragment,像我一样,这个回调方法必须在Activity包含Fragment.