我有一个Post / Category manyToMany关系,并希望能够将一个名为“未分类”的默认类别附加到所创建的每个新帖子中。我怎样才能做到这一点? BelongsToMany方法仅在“详细信息”页面上起作用,而不在“创建”页面上起作用。
BelongsToMany::make(__('Categories'), 'categories', Category::class),
答案 0 :(得分:2)
您还可以在数据库字段中设置默认值,以便您可以省略传递类别,并且默认为未归类,例如,如果您使用的是MySQL,则可以通过创建迁移来做到这一点< / p>
$table->text('category')->default(0);
答案 1 :(得分:0)
因为在Post Nova模型中创建的模式下未显示BelongsToMany。因此,我们必须通过将以下代码添加到您的字段中来进行自定义选择:
public function fields(Request $request)
{
if($request->editMode=="create"){
$categories = \App\Category::get(['id','name']);
$options = [];
foreach($categories as $value){
$options[$value->id] = $value->name;
}
return [
ID::make()->sortable(),
Text::make('Title'),
Text::make('Summary'),
Textarea::make('Content'),
Select::make('Categories', 'category_id')
->options($options)
->displayUsingLabels()
->withMeta(['value' => 1]) // 1 = id of Uncategorised in categories table
];
}
return [
ID::make()->sortable(),
Text::make('Title'),
Text::make('Summary'),
Textarea::make('Content'),
BelongsToMany::make('Categories','categories')->display('name'),
];
}
在帖子和类别模型中都不要忘记关系功能:
class Post extends Model
{
public function categories(){
return $this->belongsToMany(Category::class, 'category_post', 'post_id', 'category_id');
}
}
并且:
class Category extends Model
{
public function posts(){
return $this->belongsToMany(Post::class,'category_post', 'category_id', 'post_id');
}
}
然后,自定义函数在POST资源页面创建模式下处理数据,位于nova \ src \ Http \ Controllers \ ResourceStoreController.php,将函数句柄更改为此:
public function handle(CreateResourceRequest $request)
{
$resource = $request->resource();
$resource::authorizeToCreate($request);
$resource::validateForCreation($request);
$model = DB::transaction(function () use ($request, $resource) {
[$model, $callbacks] = $resource::fill(
$request, $resource::newModel()
);
if ($request->viaRelationship()) {
$request->findParentModelOrFail()
->{$request->viaRelationship}()
->save($model);
} else {
$model->save();
// your code to save to pivot category_post here
if(isset($request->category_id)&&($resource=='App\Nova\Post')){
$category_id = $request->category_id;
$post_id = $model->id;
\App\Post::find($post_id)->categories()->attach($category_id);
}
}
ActionEvent::forResourceCreate($request->user(), $model)->save();
collect($callbacks)->each->__invoke();
return $model;
});
return response()->json([
'id' => $model->getKey(),
'resource' => $model->attributesToArray(),
'redirect' => $resource::redirectAfterCreate($request, $request->newResourceWith($model)),
], 201);
}
}
在我的计算机上,所有程序运行良好。我有一个有趣的问题!希望对您最好,问我是否需要!
答案 2 :(得分:0)
我最终要做的是将数据保存在boot()中的Post Model上。
public static function boot()
{
parent::boot();
static::created(function (Post $post) {
$post->categories()->attach([1]);
});
}