在android活动中不会回调onRequestPermissionsResult

Question

我正在尝试在启动照相机活动之前从用户处获得照相机权限。onRequestPermissionsResult在用户从权限对话框中按“允许”后不会被回调。这是我的活动课：

public class ImageCaptureActivity extends AppCompatActivity {

    public static final String TAG = ImageCaptureActivity.class.getSimpleName();

    private static final int REQUEST_CAMERA = 0;
    private static final int REQUEST_CAMERA_PERMISSION = 1;
    private Point mSize;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_image_capture);

        Display display = getWindowManager().getDefaultDisplay();
        mSize = new Point();
        display.getSize(mSize);

        // Request for Camera Permission
        requestForCameraPermission(findViewById(android.R.id.content));
    }

    /**
     * @param view
     * @brief requestForCameraPermission
     */
    public void requestForCameraPermission(View view) {
        Log.v(TAG, "Requesting Camera Permission");

        final String permission = Manifest.permission.CAMERA;
        if (ContextCompat.checkSelfPermission(ImageCaptureActivity.this, permission)
                != PackageManager.PERMISSION_GRANTED) {
            if (ActivityCompat.shouldShowRequestPermissionRationale(ImageCaptureActivity.this, permission)) {
                showPermissionRationaleDialog(getString(R.string.camera_permission_rationale), permission);
            } else {
                requestForPermission(permission);
            }
        } else {
            launch();
        }
    }

    /**
     * @param message
     * @param permission
     * @brief showPermissionRationaleDialog
     */
    private void showPermissionRationaleDialog(final String message, final String permission) {
        new AlertDialog.Builder(ImageCaptureActivity.this)
                .setMessage(message)
                .setPositiveButton("Ok", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        ImageCaptureActivity.this.requestForPermission(permission);
                    }
                })
                .setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {

                    }
                })
                .create()
                .show();
    }

    /**
     * @param permission
     * @brief requestForPermission
     */
    private void requestForPermission(final String permission) {
        ActivityCompat.requestPermissions(ImageCaptureActivity.this, new String[]{permission}, REQUEST_CAMERA_PERMISSION);
    }

    /**
     * @brief launch
     */
    private void launch() {
        Log.v(TAG, "Camera Permission Granted, launching the CameraActivity");
        String documentId = getIntent().getStringExtra(IntentNames.INTENT_EXTRA_WIP_DOCUMENT_ID);
        Intent startCustomCameraIntent = new Intent(this, CameraActivity.class);
        startCustomCameraIntent.putExtra(IntentNames.INTENT_EXTRA_WIP_DOCUMENT_ID, documentId);
        startActivityForResult(startCustomCameraIntent, REQUEST_CAMERA);
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        switch (requestCode) {
            case REQUEST_CAMERA_PERMISSION:
                final int numOfRequest = grantResults.length;
                final boolean isGranted = numOfRequest == 1
                        && PackageManager.PERMISSION_GRANTED == grantResults[numOfRequest - 1];
                Log.v(TAG, "Camera Permission callback on onRequestPermissionsResult");
                if (isGranted) {
                    launch();
                }
                break;

            default:
                super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        }
    }
}

以下是具有摄像头权限的我的应用程序清单：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.myapp.testpackage">

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

    <uses-feature
        android:name="android.hardware.camera.front"
        android:required="true" />
    <uses-feature android:name="android.hardware.camera2" />

    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

    <application

我的Gradle依赖：

compile 'com.android.support:appcompat-v7:24.0.0'

compile 'com.android.support:design:24.0.0'

compile 'com.android.support:support-v4:24.0.0'

Answer 1

我自己试过你的代码，一切都很好。我认为唯一可能出现问题的是当您的活动具有以下两个标志时的场景：

 android:noHistory="true"
 android:excludeFromRecents="true"

下面是一个解释问题的人：https://stackoverflow.com/a/35772265/5281581