Laravel 4 - Call to a member function actividads() on a non-object (pivote table)

Question

I'm trying to save in my DB the relation between two tables actividads and fichas (through a pivot table: actividad-ficha. And I'm having this message:

Symfony \ Component \ Debug \ Exception \ FatalErrorException (E_ERROR)

Call to a member function actividads() on a non-object

I pass through my Route two variables (ids):

Route::get('ficha/{id_ficha}/{id_actividad}', array('uses' => 'FichaController@enFicha'));

And then, in my 'FichaController':

public function enFicha($id_ficha, $id_actividad)
{
        $ficha = Ficha::find($id_ficha);
       // $actividad_id = Actividad::find($id_actividad); (doesnt work)
        $actividad_id = $id_actividad; 
        $ficha->actividads()->sync($actividad_id, false);

        return Redirect::route('actividads.index'); 
}

Here my models:

class Actividad extends Eloquent {
protected $guarded = array();
public function fichas()
{       
    return $this->belongsToMany('Ficha', 'actividad_ficha')->withTimestamps(); //
}

class Ficha extends Eloquent {
protected $guarded = array();
public function actividads()
{
    return $this->belongsToMany('Actividad', 'actividad_ficha')->withTimestamps();
}

After change what @decco and @Ben suggested me, I have the next error message:

Argument 1 passed to Illuminate\Database\Eloquent\Relations\BelongsToMany::formatSyncList() must be of the type array, string given, called in /Applications/XAMPP/xamppfiles/htdocs/webs/lara4/edu1/vendor/laravel/framework/src/Illuminate/Database/Eloquent/Relations/BelongsToMany.php on line 578 and defined 

I don't know what is wrong with that... Any idea??

Thank you very much!!

Answer 1

$ficha = $id_ficha;
$ficha->actividads()->sync($actividad_id);

There's your problem. $ficha is a String, not an object.

Change the first line with $ficha = Ficha::find($id_ficha) which should return the Ficha object with ID $ficha_id or null.

Also you need to change the second line with $ficha->actividads()->attach($actividad_id).