android判断是否打开了通知权限

源码实现

 public boolean areNotificationsEnabled() {
        if (Build.VERSION.SDK_INT >= 24) {
            return mNotificationManager.areNotificationsEnabled();
        } else if (Build.VERSION.SDK_INT >= 19) {
            AppOpsManager appOps =
                    (AppOpsManager) mContext.getSystemService(Context.APP_OPS_SERVICE);
            ApplicationInfo appInfo = mContext.getApplicationInfo();
            String pkg = mContext.getApplicationContext().getPackageName();
            int uid = appInfo.uid;
            try {
                Class<?> appOpsClass = Class.forName(AppOpsManager.class.getName());
                Method checkOpNoThrowMethod = appOpsClass.getMethod(CHECK_OP_NO_THROW, Integer.TYPE,
                        Integer.TYPE, String.class);
                Field opPostNotificationValue = appOpsClass.getDeclaredField(OP_POST_NOTIFICATION);
                int value = (int) opPostNotificationValue.get(Integer.class);
                return ((int) checkOpNoThrowMethod.invoke(appOps, value, uid, pkg)
                        == AppOpsManager.MODE_ALLOWED);
            } catch (ClassNotFoundException | NoSuchMethodException | NoSuchFieldException
                    | InvocationTargetException | IllegalAccessException | RuntimeException e) {
                return true;
            }
        } else {
            return true;
        }
    }

代码直接调用

NotificationManagerCompat.from(context).areNotificationsEnabled()

跳转到设置页面

if (!NotificationsUtils.isNotificationEnabled(this)) {
            final AlertDialog dialog = new AlertDialog.Builder(this).create();
            dialog.show();

            View view = View.inflate(this, R.layout.dialog, null);
            dialog.setContentView(view);

            TextView context = (TextView) view.findViewById(R.id.tv_dialog_context);
            context.setText("检测到您没有打开通知权限，是否去打开");

            TextView confirm = (TextView) view.findViewById(R.id.btn_confirm);
            confirm.setText("确定");
            confirm.setOnClickListener(new View.OnClickListener() {
                public void onClick(View v) {
                    dialog.cancel();
                    Intent localIntent = new Intent();
                    localIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                    if (Build.VERSION.SDK_INT >= 9) {
                        localIntent.setAction("android.settings.APPLICATION_DETAILS_SETTINGS");
                        localIntent.setData(Uri.fromParts("package", MainActivity.this.getPackageName(), null));
                    } else if (Build.VERSION.SDK_INT <= 8) {
                        localIntent.setAction(Intent.ACTION_VIEW);

                        localIntent.setClassName("com.android.settings",
                                "com.android.settings.InstalledAppDetails");

                        localIntent.putExtra("com.android.settings.ApplicationPkgName",
                                MainActivity.this.getPackageName());
                    }
                    startActivity(localIntent);
                }
            });

            TextView cancel = (TextView) view.findViewById(R.id.btn_off);
            cancel.setOnClickListener(new View.OnClickListener() {
                public void onClick(View v) {
                    dialog.cancel();
                }
            });
      }