PHP致命错误：在Laravel4中播种期间调用未定义的方法setContainer（）

Question

我试图在用户和角色之间建立n：n关系。 迁移是可以的，但是当我尝试在RoleUserTableSeeder上播种数据库时，控制台会给我这个错误：

  

PHP致命错误：在第57行的/var/www/laravel/vendor/laravel/framework/src/Illuminate/Database/Seeder.php中调用未定义的方法CreateForeignKeys :: setContainer（）   {＆＃34;错误＆＃34; {＆＃34;类型＆＃34;：＆＃34; Symfony的\元器件\调试\异常\ FatalErrorException＆＃34;＆＃34;消息＆＃34;：＆＃34;调用未定义的方法CreateForeignKeys :: setContainer（）＆＃34;，＆＃34; file＆＃34;：＆＃34; /var/www/laravel/vendor/laravel/framework/src/Illuminate/Database/Seeder.php& ＃34;＆＃34;线＆＃34; 57}}

这些是我的迁移：

2014_10_27_153245_create_users_table.php

<?php

    use Illuminate\Database\Schema\Blueprint;
    use Illuminate\Database\Migrations\Migration;

    class CreateUsersTable extends Migration {
        public function up()
        {
            Schema::create('users', function($t) {
                $t->string('name', 50);
                $t->string('surname', 50);
                $t->string('email', 100);
                $t->string('username', 20);
                $t->string('password', 60);
                $t->string('remember_token', 100);
                $t->timestamps();
                $t->primary('username');
            });
        }

        public function down()
        {
            Schema::drop('users');
        }
    }
?>

2014_10_29_162948_create_roles_table.php

<?php

    use Illuminate\Database\Schema\Blueprint;
    use Illuminate\Database\Migrations\Migration;

    class CreateRolesTable extends Migration {

        public function up()
        {
            Schema::create('roles', function($t) {
                $t->increments('id');
                $t->string('role',50)->unique();
                $t->timestamps();
            });
    }

    public function down()
    {
        Schema::drop('roles');
    }

}

?>

2014_10_29_163350_create_role_user_table.php

<?php

    use Illuminate\Database\Schema\Blueprint;
    use Illuminate\Database\Migrations\Migration;

    class CreateRoleUserTable extends Migration {

        public function up()
        {
            Schema::create('role_user', function($t) {
                $t->increments('id');
                $t->integer('role_id')->unsigned();
                $t->string('user_username');
            });
        }

        public function down()
        {
            Schema::drop('role_user');
        }

    }

    ?>

2014_10_29_163723_create_foreign_keys.php

<?php


    use Illuminate\Database\Schema\Blueprint;
    use Illuminate\Database\Migrations\Migration;

    class CreateForeignKeys extends Migration {

        public function up()
        {   
            Schema::table('role_user', function($t) {
                $t->foreign('role_id')->references('id')->on('roles')
                    ->onUpdate('cascade');
        });
        Schema::table('role_user', function($t) {
            $t->foreign('user_username')->references('username')->on('users')
                ->onUpdate('cascade');
        });
    }

    public function down()
    {
        Schema::table('role_user', function($t) {
            $t->dropForeign('role_user_role_id_foreign');
        });
        Schema::table('role_user', function($t) {
            $t->dropForeign('role_user_user_username_foreign');
        });
    }

}

?>

......这些是我的播种机：

UserTableSeeder.php

<?php

    ## Seeder for the user table to create the admin user
    class UserTableSeeder extends Seeder 
    {
        public function run()
        {
            DB::table('users')->delete();
            DB::table('users')->insert(array(
                'name'      => 'xxxx',
                'surname'   => 'xxxx',
                'email'     => 'xxxx@yyyy.com',
                'password'  => Hash::make('admin'),
                'username'  => 'admin',
            ));
        }
    }
?>

RoleTableSeeder.php

<?php

    ## Seeder for the role table to create the admin user
    class RoleTableSeeder extends Seeder 
    {
        public function run()
        {
            DB::table('roles')->delete();
            DB::table('roles')->insert(array(
                'role'      => 'admin'
            ));
        }
    }

?>

RoleUserTableSeeder.php

<?php

    ## Seeder for the role_user table to create the admin user
    class RoleUserTableSeeder extends Seeder 
    {
        public function run()
        {
            DB::table('role_user')->delete();
            DB::table('role_user')->insert(array(
                'user_username' => 'admin',
                'role_id' => Role::getId('admin')
            ));
        }
    }

?>

这是我在角色模型中的getId函数：

Role.php

...
## Return the id of a role
public static function getId($mansion) {
    return Role::where('role','=',$mansion)->pluck('id');
}
...

有人可以帮我解决这个错误吗？ 谢谢！