laravel-admin中实现三级联动筛选搜索功能流程步骤

网上大部分写的比较模糊，刚好我的项目需要做这个功能，我这就根据我的项目实现省市区三级列表筛选搜索功能，记录一下

开始环境啥的就不说了，就是laravel-admin

1.表结构

CREATE TABLE `city` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `title` char(30) DEFAULT NULL,
  `pid` int(11) DEFAULT NULL,
  `created_at` timestamp NULL DEFAULT NULL,
  `updated_at` timestamp NULL DEFAULT NULL ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`) USING BTREE,
  KEY `pid` (`pid`) USING BTREE,
  KEY `t` (`title`) USING BTREE
) ENGINE=InnoDB AUTO_INCREMENT=3896 DEFAULT CHARSET=utf8 ROW_FORMAT=DYNAMIC;

2.模型

<?php
namespace App\Models;
use Encore\Admin\Form;
use Encore\Admin\Grid;
use Illuminate\Database\Eloquent\Model;

class Wdcity extends Model
{
    protected $table = 'city';
    
    public static function grid($callback)
    {
        return new Grid(new static, $callback);
    }
    
    public static function form($callback)
    {
        return new Form(new static, $callback);
    }
    
    public function parent()
    {
        return $this->belongsTo(Wdcity::class, 'pid');
    }
    
    public function children()
    {
        return $this->hasMany(Wdcity::class, 'pid');
    }
    
    public function brothers()
    {
        return $this->parent->children();
    }
    
    public static function options($id)
    {
        if (! $self = static::find($id)) {
            return [];
        }
        return $self->brothers()->pluck('title', 'id');
    }
}

3.控制器中 联动接口调用

<?php
namespace App\Admin\Controllers;
use App\Models\Wdcity;
use App\Models\SelectOption;
use Encore\Admin\Controllers\HasResourceActions;
use Encore\Admin\Form;
use Encore\Admin\Grid;
use Encore\Admin\Layout\Content;
use App\Http\Controllers\Controller;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;
class WdcityController extends Controller
{
    use HasResourceActions;
    
    private $title = '城市管理';
    
    private $states = [
        'on'  => ['value' => 0, 'text' => '否', 'color' => 'danger'],
        'off' => ['value' => 1, 'text' => '是', 'color' => 'success'],
    ];
    
    public function city(Request $request)
    {
        $pid = $request->get('q');
        return Wdcity::where('pid', $pid)->get(['id', DB::raw('title as text')]);
    }
    
    public function district(Request $request)
    {
        $cityId = $request->get('q');
        return Wdcity::where('pid', $cityId)->get(['id', DB::raw('title as text')]);
    }
}

4.路由

$router->get('api/wdcity/city', '[email protected]');
$router->get('api/wdcity/district', '[email protected]');

5.筛选中调用  实现省市区三级联动

    /**
     * Make a grid builder.
     *
     * @return Grid
     */
    protected function grid()
    {
        $grid = new Grid(new Bankwd());
        $grid->id('ID')->sortable();
        
        $grid->filter(function($filter){
            // 去掉默认的id过滤器
            //$filter->disableIdFilter();
            
            $filter->like('bankname','名称');
            $filter->equal('bankid','银行')->select(SelectOption::wdbanktypelist());
    
                //这里就是三级联动调用
            $filter->equal('citys1', '省份')->select(Wdcity::where('pid',0)->orderBy('title')->pluck('title', 'id'))
                ->load('citys2', '/api/wdcity/city');
                
            $filter->equal('citys2', '城市')->select(Wdcity::where('pid','<>',0)->orderBy('title')->pluck('title', 'id'))
                ->load('city3', '/api/wdcity/district');
                
            $filter->equal('city3', '区')->select(function ($id) {
                return Wdcity::options($id);
            });
            
        });
        
        return $grid;
    }

6.废话不多说 直接看效果

完