PHP 从另一个命名空间调用抽象类方法答案

【问题标题】：PHP Call abstract class method from another namespacePHP 从另一个命名空间调用抽象类方法
【发布时间】：2021-01-06 10:24:36
【问题描述】：

我有类 OnboardingConversation，我从命名空间 BotMan\BotMan\Messages\Conversations\Conversation 调用方法 say

namespace PanObed\Conversations;
use BotMan\BotMan\Messages\Conversations\Conversation;

class OnboardingConversation extends Conversation{

      protected $name;
 
        public function __construct() {

        return $this->run();

        }

      public function run() {

        $this->say("Say hello");

      }
}

还有类 BotMan\BotMan\Messages\Conversations\Conversation

namespace BotMan\BotMan\Messages\Conversations;

use BotMan\BotMan\BotMan;
use BotMan\BotMan\Interfaces\ShouldQueue;
use BotMan\BotMan\Messages\Attachments\Audio;
use BotMan\BotMan\Messages\Attachments\Contact;
use BotMan\BotMan\Messages\Attachments\File;
use BotMan\BotMan\Messages\Attachments\Image;
use BotMan\BotMan\Messages\Attachments\Location;
use BotMan\BotMan\Messages\Attachments\Video;
use BotMan\BotMan\Messages\Incoming\IncomingMessage;
use BotMan\BotMan\Messages\Outgoing\Question;
use Closure;
use Illuminate\Support\Collection;
use Spatie\Macroable\Macroable;

abstract class Conversation
{

     use Macroable;

    /**
     * @var BotMan
     */
    protected $bot;

    public function say($message, $additionalParameters = [])
    {
        $this->bot->reply($message, $additionalParameters);

        return $this;
    }
}

但是有一个问题，当我调用 new OnboardingConversation 时出现此错误：

<br />
<b>Fatal error</b>:  Uncaught Error: Call to a member function reply() on null in C:\xampp\htdocs\panobed\bot\vendor\botman\botman\src\Messages\Conversations\Conversation.php:205
Stack trace:
#0 C:\xampp\htdocs\panobed\bot\class\Conversations\OnboardingConversation.php(32): BotMan\BotMan\Messages\Conversations\Conversation-&gt;say('Test')
#1 C:\xampp\htdocs\panobed\bot\class\Conversations\OnboardingConversation.php(23): PanObed\Conversations\OnboardingConversation-&gt;run()
#2 C:\xampp\htdocs\panobed\bot\index.php(27): PanObed\Conversations\OnboardingConversation-&gt;__construct()
#3 [internal function]: {closure}(Object(BotMan\BotMan\BotMan))
#4 C:\xampp\htdocs\panobed\bot\vendor\botman\botman\src\BotMan.php(495): call_user_func_array(Object(Closure), Array)
#5 C:\xampp\htdocs\panobed\bot\vendor\botman\botman\src\BotMan.php(425): BotMan\BotMan\BotMan-&gt;callMatchingMessages()
#6 C:\xampp\htdocs\panobed\bot\index.php(32): BotMan\BotMan\BotMan-&gt;listen()
#7 {main}
  thrown in <b>C:\xampp\htdocs\panobed\bot\vendor\botman\botman\src\Messages\Conversations\Conversation.php</b> on line <b>205</b><br />

如果我不使用命名空间PanObed\Conversations，代码是可以的。那么你能告诉我，我做错了什么吗？

谢谢

【问题讨论】：

标签： php class methods abstract

【解决方案1】：

您似乎没有在任何地方设置$this->bot 属性。

你应该在OnboardingConversation::__constructor 中初始化它。使用正确的对象初始化$this->bot 后，您的代码应该能够调用$this->bot->reply(...)

【讨论】：