Summary of Laravel Assigning Values to Common Templates

Many times in the development process, common templates are assigned values, such as the top navigation bar, the bottom of the page, etc. It is impossible to assign values once in every controller.

The solution in Laravel is as follows: Modify

App\Providers\AppServiceProvider

Add in the boot method

View()->composer('common.header',function ($view){ //common.header  Correspondence Blade Template  $view->with('key', 'value'); });

You can also assign values to all templates

View()->share('key', 'value');

view composers is related to views, and is used in the boot () function of an service provider, that is, when an view is loaded, due to the role of view composer, it calls a certain function to pass a parameter or something.

1. Create service provider

php artisan make:provider ComposerServiceProvider

Add ComposerServiceProvider to config/app.php Inside

2. Write view composer

public function boot()  {    view()->composer(      'app', // Template name       'App\Http\ViewComposers\MovieComposer' // Method name or method in class     );  }

It means that once app. blade. php is loaded, it is executed App\Http\ViewComposers\MovieComposer In composer Function (the reason why composer function is executed here is the default), if you want to change one, just

view()->composer('app','App\Http\ViewComposers\MovieComposer@foobar'); //Self-defined method

The foobar function is executed here

In App\Http\ViewComposers\MovieComposer.php It says so in the book

<?phpnamespace App\Http\ViewComposers;use Illuminate\View\View;//** Remember to introduce this (because in composer Function parameter uses the View Class) **class MovieComposer{  public $movieList = [];  public function __construct()  {    $this->movieList = [      'Shawshank redemption',      'Forrest Gump',    ];  }  public function compose(View $view)  {    $view->with('latestMovie');  }}

3. When all templates are needed, use * regular expressions

view()->composer('*', function (View $view) {  //logic goes here});

To specify multiple view uses, wrap them in an array

view()->composer(['nav', 'footer'],'App\Http\ViewComposers\MovieComposer'); Or  view()->composer(['admin.admin'], function ($view){      $column = $this->object_array(DB::table('column')->get());      foreach($column as $k=>$v){        $chid = explode(',',$v['childid']);        foreach($chid as $value){          $column[$k]['chname'][] = $this->object_array(DB::table('column_child')->where('id',$value)->first());        }      }      $view->with('columns',$column);    });