6.+ 的权限检测工具类

6.0 刚出来，曾简单封装过一个工具类，今天，再完善了，一下，踢出了不要的代码；

https://github.com/zhaoyubetter/PermissionCheck

使用方法

1. 在使用初检测：

 findViewById(R.id.requestOne).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                PermissionUtils.checkPermissions(MainActivity.this, 
                          new String[]{Manifest.permission.CAMERA}, "照相机", new Runnable() {
                    @Override
                    public void run() {
                          // 执行操作
                    }
                });
            }
        });

2. onRequestPermissionsResult方法的复写：

   @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        PermissionUtils.requestResult(requestCode, permissions, grantResults, new Runnable() {
            @Override
            public void run() {
                // 权限获取成功执行的代码
            }
        }, new Runnable() {
            @Override
            public void run() {
                // 权限获取失败执行的代码
            }
        });
    }

工具类代码如下：

public final class PermissionUtils {
    public static final int REQUEST_CODE = 20;

    /**
     * 请求权限
     *
     * @param obj
     * @param reqPermissions 权限列表
     * @param explain        申请权限解释说明
     * @param runnable       有权限时，执行的runnable
     */
    public static void checkPermissions(final Object obj, final String[] reqPermissions, final String explain, final Runnable runnable) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            // 检测类型
            Activity activity = getActivity(obj);
            if (activity == null || reqPermissions == null) {
                return;
            }

            // 需要申请的权限
            final List<String> needReqList = new ArrayList<>();

            // 一次申请多个权限
            boolean needShowExplain = false;
            for (int i = 0; i < reqPermissions.length; i++) {
                needShowExplain = addPermission(obj, needReqList, reqPermissions[i]);
            }

            // 有权限需要申请
            if (needReqList.size() > 0 && !activity.isFinishing()) {
                if (!TextUtils.isEmpty(explain) && needShowExplain) {
                    AlertDialog.Builder builder = new AlertDialog.Builder(activity);
                    builder.setMessage(explain);
                    builder.setCancelable(false);
                    builder.setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialog, int which) {
                            request(obj, needReqList);
                        }
                    });
                    builder.create().show();
                } else {
                    request(obj, needReqList);
                }
            } else {
                if (runnable != null) {
                    runnable.run();
                }
            }
        } else {
            if (runnable != null) {
                runnable.run();
            }
        }
    }

    /**
     * 权限请求结果
     * onRequestPermissionsResult 调用
     *
     * @param requestCode
     * @param permissions
     * @param grantResults
     * @param successRunnable 权限获取成功，执行的任务
     * @param failRunnable    权限获取失败，执行的任务
     */
    public static void requestResult(int requestCode, String[] permissions, int[] grantResults, final Runnable successRunnable, final Runnable failRunnable) {
        if (requestCode == REQUEST_CODE) {
            boolean isGranted = true;
            int size = permissions.length;
            for (int i = 0; i < size; i++) {
                if (grantResults[i] != PackageManager.PERMISSION_GRANTED) {
                    isGranted = false;
                    break;
                }
            }
            if (isGranted && successRunnable != null) {
                successRunnable.run();     // 执行任务
            } else if (!isGranted && failRunnable != null) { //  权限被拒绝
                failRunnable.run();     // 执行任务
            }
        }
    }

    /**
     * 请求权限
     *
     * @param object
     * @param permissionsList
     */
    private static void request(final Object object, List<String> permissionsList) {
        if (object instanceof Activity) {
            ActivityCompat.requestPermissions((Activity) object, permissionsList.toArray(new String[permissionsList.size()]), REQUEST_CODE);
        } else if (object instanceof Fragment) {
            ((Fragment) object).requestPermissions(permissionsList.toArray(new String[permissionsList.size()]), REQUEST_CODE);
        }
    }

    /**
     * 添加要求权限列表
     *
     * @param obj
     * @param permissionsList
     * @param permission
     * @return true 表示需要解释，false不需要
     */
    private static boolean addPermission(final Object obj, List<String> permissionsList, String permission) {
        // 检测类型
        Activity activity = getActivity(obj);
        if (activity == null) {
            return true;
        }

        if (ContextCompat.checkSelfPermission(activity, permission) != PackageManager.PERMISSION_GRANTED) {
            permissionsList.add(permission);
            if (ActivityCompat.shouldShowRequestPermissionRationale(activity, permission)) {
                return true;
            }
        }
        return false;
    }

    /**
     * 获取权限请求的acitivity
     *
     * @param obj
     * @return
     */
    private static Activity getActivity(final Object obj) {
        Activity activity = null;
        if (obj instanceof Activity) {
            activity = (Activity) obj;
        } else if (obj instanceof Fragment) {
            Fragment fragment = (Fragment) obj;
            activity = fragment.isAdded() ? fragment.getActivity() : null;
        } else if (obj instanceof android.app.Fragment) {
            Fragment fragment = (Fragment) obj;
            activity = fragment.isAdded() ? fragment.getActivity() : null;
        } else {
            throw new IllegalArgumentException("不支持的参数类型：" + obj.getClass());
        }
        return activity;
    }
}