老是用RxPermission请求权限，总觉得麻烦，所以索性花了半小时自己写了一个工具类
不支持Permission_group请求
在Rxjava上又封了一层强行链式结构enmmmm

使用：

PermissionUtils.requestPermission(BaseInfoActivity.this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE, Manifest.permission.WRITE_EXTERNAL_STORAGE, Manifest.permission.CAMERA}, Config.PERMISSIONS_REQUEST_PHOTO)
                    .subscribe(new PermissionUtils.RequestPermissionObserver() {

                        @Override
                        public void shouldShowRequestPermissionRationale(final List<String> shouldAskPermissions) {
                            new AlertDialog.Builder(BaseInfoActivity.this).setTitle("不给相册相关的权限真的无法录头像哦~").setPositiveButton("还是给你吧", new DialogInterface.OnClickListener() {
                                @Override
                                public void onClick(DialogInterface dialog, int which) {
                                    PermissionUtils.requestPersimsion(BaseInfoActivity.this, shouldAskPermissions.toArray(new String[]{}), Config.PERMISSIONS_REQUEST_PHOTO);
                                }
                            }).setNegativeButton("我不爱放头像", null).show();
                        }

                        @Override
                        public void hadPermission(List<String> hadPermissions) {

                        }

                        @Override
                        public void allPermissionGranter() {
                            selectAvatarImage();
                        }
                    });

以下是整体代码

/**
 * Created by lip on 2018/5/7.
 * e:chenkenLip@163.com
 */

public class PermissionUtils {

    public static boolean checkPermission(Context context, String permission) {
    boolean ret = false;
    int checkSelfPermission = PermissionChecker.checkSelfPermission(context, permission);
    if (checkSelfPermission == PackageManager.PERMISSION_GRANTED) {
        ret = true;
    }
    return ret;
}

public static void requestPersimsion(Activity activity, String permission, int requestCode) {
    ActivityCompat.requestPermissions(activity,
            new String[]{permission},
            requestCode);
}

public static void requestPersimsion(Activity activity, String[] permissions, int requestCode) {
    ActivityCompat.requestPermissions(activity,
            permissions,
            requestCode);
}

public static Observable<PermissionData> requestPermission(final Activity activity, final String[] permissions, final int requestCode) {
    return Observable.create(new ObservableOnSubscribe<PermissionData>() {
        @Override
        public void subscribe(ObservableEmitter<PermissionData> observableEmitter) throws Exception {
            List<String> couldReuqestPermissions = new ArrayList<>();
            List<String> shouldAskPermissions = new ArrayList<>();
            List<String> hadPermissions = new ArrayList<>();
            for (String permission : permissions) {
                if (!checkPermission(activity, permission)) {
                    if (ActivityCompat.shouldShowRequestPermissionRationale(activity,
                            permission)) {
                        shouldAskPermissions.add(permission);
                    } else {
                        couldReuqestPermissions.add(permission);
                    }
                } else {
                    hadPermissions.add(permission);
                }
            }
            if (couldReuqestPermissions.size() != 0) {
                requestPersimsion(activity, couldReuqestPermissions.toArray(new String[]{}), requestCode);
            }
            PermissionData permissionData = new PermissionData();
            permissionData.setHadPermissions(hadPermissions);
            permissionData.setShouldAskPermissions(shouldAskPermissions);
            permissionData.setPermissionsCount(permissions.length);
            observableEmitter.onNext(permissionData);
        }
    }).observeOn(AndroidSchedulers.mainThread()).subscribeOn(AndroidSchedulers.mainThread());
}

public abstract static class RequestPermissionObserver implements Observer<PermissionData> {

    @Override
    public void onSubscribe(Disposable disposable) {

    }

    @Override
    public void onNext(PermissionData data) {
        if (data.getShouldAskPermissions().size() != 0) {
            shouldShowRequestPermissionRationale(data.getShouldAskPermissions());
        }
        if (data.getHadPermissions().size() != 0) {
            hadPermission(data.getHadPermissions());
        }
        if (data.hadPermissions.size() == data.getPermissionsCount()) {
            allPermissionGranter();
        }
    }

    @Override
    public void onError(Throwable throwable) {
        Logger.i("lip--" + throwable.toString());
    }

    @Override
    public void onComplete() {

    }

    public abstract void shouldShowRequestPermissionRationale(List<String> shouldAskPermissions);

    public abstract void hadPermission(List<String> hadPermissions);

    public abstract void allPermissionGranter();
}

private static class PermissionData {

    private int permissionsCount;

    private List<String> shouldAskPermissions;

    private List<String> hadPermissions;

    public int getPermissionsCount() {
        return permissionsCount;
    }

    public void setPermissionsCount(int permissionsCount) {
        this.permissionsCount = permissionsCount;
    }

    public List<String> getShouldAskPermissions() {
        return shouldAskPermissions;
    }

    public void setShouldAskPermissions(List<String> shouldAskPermissions) {
        this.shouldAskPermissions = shouldAskPermissions;
    }

    public List<String> getHadPermissions() {
        return hadPermissions;
    }

    public void setHadPermissions(List<String> hadPermissions) {
        this.hadPermissions = hadPermissions;
    }
}
}