Anomalie d'affichage d'un menu dynamique angular 9

Bonjour,

En essayant d'utiliser le menu dynamique proposé par https://stackblitz.com/edit/dynamic-...%2Fnav-item.ts dans mon projet angular (version 9.0.5) qui utilise le template Material Dashboard Angular (https://www.creative-tim.com/product...board-angular2), je rencontre une anomalie au niveau de l'affichage de menu. En chargeant ma page web, seul le premier élément de menu s'affiche, les autres éléments de menu s'affichent l'un après l'autre en cliquant sur le premier élément affiché.

L'intégration de l'exemple de menu dans mon projet est comme suit: j'ai placé le composant MenuItemComponent sous le dossier "components" et je l'ai importé et déclaré dans le module "ComponentsModule" puis j'ai placé le code de menu dans le template "nav-bar.component.html" après avoir déclaré le tableau contenant les éléments de menu dans le composant "NavbarComponent" comme suit:

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 // ComponentsModule 
 
import { NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';
import { RouterModule } from '@angular/router';
 
import { FooterComponent } from './footer/footer.component';
import { NavbarComponent } from './navbar/navbar.component';
import { SidebarComponent } from './sidebar/sidebar.component';
import { MenuItemComponent } from './menu-item/menu-item.component';
 
 
 
import { MatButtonModule} from '@angular/material/button';
import { MatIconModule} from '@angular/material/icon';
import { MatMenuModule} from '@angular/material/menu';
import { MatToolbarModule} from '@angular/material/toolbar';
 
 
@NgModule({
  exports: [
    FooterComponent,
    NavbarComponent,
    SidebarComponent,
    MenuItemComponent,
  ],
  imports: [
    CommonModule,
    RouterModule,
 
    MatIconModule,
    MatButtonModule,
    MatMenuModule,
    MatToolbarModule
 
  ],
  declarations: [
    FooterComponent,
    NavbarComponent,
    SidebarComponent,
    MenuItemComponent,
  ],
 
})
export class ComponentsModule { }

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  // NavbarComponent
 
import { Component, OnInit, ElementRef } from '@angular/core';
import { ROUTES } from '../sidebar/sidebar.component';
import {Location, LocationStrategy, PathLocationStrategy} from '@angular/common';
import { Router } from '@angular/router';
import {NavItem} from '../nav-item';
 
@Component({
  selector: 'app-navbar',
  templateUrl: './navbar.component.html',
  styleUrls: ['./navbar.component.css']
})
export class NavbarComponent implements OnInit {
    private listTitles: any[];
    location: Location;
      mobile_menu_visible: any = 0;
    private toggleButton: any;
    private sidebarVisible: boolean;
 
    constructor(location: Location,  private element: ElementRef, private router: Router) {
      this.location = location;
          this.sidebarVisible = false;
    }
 
    ngOnInit(){
      this.listTitles = ROUTES.filter(listTitle => listTitle);
      const navbar: HTMLElement = this.element.nativeElement;
      this.toggleButton = navbar.getElementsByClassName('navbar-toggler')[0];
      this.router.events.subscribe((event) => {
        this.sidebarClose();
         var $layer: any = document.getElementsByClassName('close-layer')[0];
         if ($layer) {
           $layer.remove();
           this.mobile_menu_visible = 0;
         }
     });
    }
 
    sidebarOpen() {
        const toggleButton = this.toggleButton;
        const body = document.getElementsByTagName('body')[0];
        setTimeout(function(){
            toggleButton.classList.add('toggled');
        }, 500);
 
        body.classList.add('nav-open');
 
        this.sidebarVisible = true;
    };
    sidebarClose() {
        const body = document.getElementsByTagName('body')[0];
        this.toggleButton.classList.remove('toggled');
        this.sidebarVisible = false;
        body.classList.remove('nav-open');
    };
    sidebarToggle() {
        // const toggleButton = this.toggleButton;
        // const body = document.getElementsByTagName('body')[0];
        var $toggle = document.getElementsByClassName('navbar-toggler')[0];
 
        if (this.sidebarVisible === false) {
            this.sidebarOpen();
        } else {
            this.sidebarClose();
        }
        const body = document.getElementsByTagName('body')[0];
 
        if (this.mobile_menu_visible == 1) {
            // $('html').removeClass('nav-open');
            body.classList.remove('nav-open');
            if ($layer) {
                $layer.remove();
            }
            setTimeout(function() {
                $toggle.classList.remove('toggled');
            }, 400);
 
            this.mobile_menu_visible = 0;
        } else {
            setTimeout(function() {
                $toggle.classList.add('toggled');
            }, 430);
 
            var $layer = document.createElement('div');
            $layer.setAttribute('class', 'close-layer');
 
 
            if (body.querySelectorAll('.main-panel')) {
                document.getElementsByClassName('main-panel')[0].appendChild($layer);
            }else if (body.classList.contains('off-canvas-sidebar')) {
                document.getElementsByClassName('wrapper-full-page')[0].appendChild($layer);
            }
 
            setTimeout(function() {
                $layer.classList.add('visible');
            }, 100);
 
            $layer.onclick = function() { //asign a function
              body.classList.remove('nav-open');
              this.mobile_menu_visible = 0;
              $layer.classList.remove('visible');
              setTimeout(function() {
                  $layer.remove();
                  $toggle.classList.remove('toggled');
              }, 400);
            }.bind(this);
 
            body.classList.add('nav-open');
            this.mobile_menu_visible = 1;
 
        }
    };
 
    getTitle(){
      var titlee = this.location.prepareExternalUrl(this.location.path());
      if(titlee.charAt(0) === '#'){
          titlee = titlee.slice( 1 );
      }
 
      for(var item = 0; item < this.listTitles.length; item++){
          if(this.listTitles[item].path === titlee){
              return this.listTitles[item].title;
          }
      }
      return 'Dashboard';
    }
 
 
 
    navItems: NavItem[] = [
      {
        displayName: 'DevFestFL',
        iconName: 'close',
        children: [
          {
            displayName: 'Speakers',
            iconName: 'group',
            children: [
              {
                displayName: 'Michael Prentice',
                iconName: 'person',
                route: 'michael-prentice',
                children: [
                  {
                    displayName: 'Create Enterprise UIs',
                    iconName: 'star_rate',
                    route: 'material-design'
                  }
                ]
              },
              {
                displayName: 'Stephen Fluin',
                iconName: 'person',
                route: 'stephen-fluin',
                children: [
                  {
                    displayName: 'What\'s up with the Web?',
                    iconName: 'star_rate',
                    route: 'what-up-web'
                  }
                ]
              },
              {
                displayName: 'Mike Brocchi',
                iconName: 'person',
                route: 'mike-brocchi',
                children: [
                  {
                    displayName: 'My ally, the CLI',
                    iconName: 'star_rate',
                    route: 'my-ally-cli'
                  },
                  {
                    displayName: 'Become an Angular Tailor',
                    iconName: 'star_rate',
                    route: 'become-angular-tailer'
                  }
                ]
              }
            ]
          },
          {
            displayName: 'Sessions',
            iconName: 'speaker_notes',
            children: [
              {
                displayName: 'Create Enterprise UIs',
                iconName: 'star_rate',
                route: 'material-design'
              },
              {
                displayName: 'What\'s up with the Web?',
                iconName: 'star_rate',
                route: 'what-up-web'
              },
              {
                displayName: 'My ally, the CLI',
                iconName: 'star_rate',
                route: 'my-ally-cli'
              },
              {
                displayName: 'Become an Angular Tailor',
                iconName: 'star_rate',
                route: 'become-angular-tailer'
              }
            ]
          },
          {
            displayName: 'Feedback',
            iconName: 'feedback',
            route: 'feedback'
          }
        ]
      },
      {
        displayName: 'Disney',
        iconName: 'close',
        children: [
          {
            displayName: 'Speakers',
            iconName: 'group',
            children: [
              {
                displayName: 'Michael Prentice',
                iconName: 'person',
                route: 'michael-prentice',
                children: [
                  {
                    displayName: 'Create Enterprise UIs',
                    iconName: 'star_rate',
                    route: 'material-design'
                  }
                ]
              },
              {
                displayName: 'Stephen Fluin',
                iconName: 'person',
                route: 'stephen-fluin',
                children: [
                  {
                    displayName: 'What\'s up with the Web?',
                    iconName: 'star_rate',
                    route: 'what-up-web'
                  }
                ]
              },
              {
                displayName: 'Mike Brocchi',
                iconName: 'person',
                route: 'mike-brocchi',
                children: [
                  {
                    displayName: 'My ally, the CLI',
                    iconName: 'star_rate',
                    route: 'my-ally-cli'
                  },
                  {
                    displayName: 'Become an Angular Tailor',
                    iconName: 'star_rate',
                    route: 'become-angular-tailer'
                  }
                ]
              }
            ]
          },
          {
            displayName: 'Sessions',
            iconName: 'speaker_notes',
            children: [
              {
                displayName: 'Create Enterprise UIs',
                iconName: 'star_rate',
                route: 'material-design'
              },
              {
                displayName: 'What\'s up with the Web?',
                iconName: 'star_rate',
                route: 'what-up-web'
              },
              {
                displayName: 'My ally, the CLI',
                iconName: 'star_rate',
                route: 'my-ally-cli'
              },
              {
                displayName: 'Become an Angular Tailor',
                iconName: 'star_rate',
                route: 'become-angular-tailer'
              }
            ]
          },
          {
            displayName: 'Feedback',
            iconName: 'feedback',
            route: 'feedback'
          }
        ]
      },
      {
        displayName: 'Orlando',
        iconName: 'close',
        children: [
          {
            displayName: 'Speakers',
            iconName: 'group',
            children: [
              {
                displayName: 'Michael Prentice',
                iconName: 'person',
                route: 'michael-prentice',
                children: [
                  {
                    displayName: 'Create Enterprise UIs',
                    iconName: 'star_rate',
                    route: 'material-design'
                  }
                ]
              },
              {
                displayName: 'Stephen Fluin',
                iconName: 'person',
                route: 'stephen-fluin',
                children: [
                  {
                    displayName: 'What\'s up with the Web?',
                    iconName: 'star_rate',
                    route: 'what-up-web'
                  }
                ]
              },
              {
                displayName: 'Mike Brocchi',
                iconName: 'person',
                route: 'mike-brocchi',
                children: [
                  {
                    displayName: 'My ally, the CLI',
                    iconName: 'star_rate',
                    route: 'my-ally-cli'
                  },
                  {
                    displayName: 'Become an Angular Tailor',
                    iconName: 'star_rate',
                    route: 'become-angular-tailer'
                  }
                ]
              }
            ]
          },
          {
            displayName: 'Sessions',
            iconName: 'speaker_notes',
            children: [
              {
                displayName: 'Create Enterprise UIs',
                iconName: 'star_rate',
                route: 'material-design'
              },
              {
                displayName: 'What\'s up with the Web?',
                iconName: 'star_rate',
                route: 'what-up-web'
              },
              {
                displayName: 'My ally, the CLI',
                iconName: 'star_rate',
                route: 'my-ally-cli'
              },
              {
                displayName: 'Become an Angular Tailor',
                iconName: 'star_rate',
                route: 'become-angular-tailer'
              }
            ]
          },
          {
            displayName: 'Feedback',
            iconName: 'feedback',
            route: 'feedback'
          }
        ]
      },
      {
        displayName: 'Maleficent',
        disabled: true,
        iconName: 'close',
        children: [
          {
            displayName: 'Speakers',
            iconName: 'group',
            children: [
              {
                displayName: 'Michael Prentice',
                iconName: 'person',
                route: 'michael-prentice',
                children: [
                  {
                    displayName: 'Create Enterprise UIs',
                    iconName: 'star_rate',
                    route: 'material-design'
                  }
                ]
              },
              {
                displayName: 'Stephen Fluin',
                iconName: 'person',
                route: 'stephen-fluin',
                children: [
                  {
                    displayName: 'What\'s up with the Web?',
                    iconName: 'star_rate',
                    route: 'what-up-web'
                  }
                ]
              },
              {
                displayName: 'Mike Brocchi',
                iconName: 'person',
                route: 'mike-brocchi',
                children: [
                  {
                    displayName: 'My ally, the CLI',
                    iconName: 'star_rate',
                    route: 'my-ally-cli'
                  },
                  {
                    displayName: 'Become an Angular Tailor',
                    iconName: 'star_rate',
                    route: 'become-angular-tailer'
                  }
                ]
              }
            ]
          },
          {
            displayName: 'Sessions',
            iconName: 'speaker_notes',
            children: [
              {
                displayName: 'Create Enterprise UIs',
                iconName: 'star_rate',
                route: 'material-design'
              },
              {
                displayName: 'What\'s up with the Web?',
                iconName: 'star_rate',
                route: 'what-up-web'
              },
              {
                displayName: 'My ally, the CLI',
                iconName: 'star_rate',
                route: 'my-ally-cli'
              },
              {
                displayName: 'Become an Angular Tailor',
                iconName: 'star_rate',
                route: 'become-angular-tailer'
              }
            ]
          },
          {
            displayName: 'Feedback',
            iconName: 'feedback',
            route: 'feedback'
          }
        ]
      }
    ];
 
 
 
}

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  // template nav-bar.component.html
 
<nav class="navbar navbar-expand-lg navbar-transparent  navbar-absolute fixed-top">
	<div class="container-fluid">
        <div class="navbar-wrapper">
 
            <!----<a class="navbar-brand" href="javascript:void(0)">{{getTitle()}}</a> -->
         <span *ngFor="let item of navItems"> 
 
            <!-- Handle branch node buttons here -->
          <span *ngIf="item.children && item.children.length > 0">
              <button mat-raised-button color="primary" [matMenuTriggerFor]="menu.childMenu"  > 
                {{item.displayName}} 
                <mat-icon>expand_more</mat-icon>
              </button>
              <app-menu-item1 #menu [items]="item.children" ></app-menu-item1>
            </span>  
            <!-- Leaf node buttons here -->
           <span *ngIf="!item.children || item.children.length === 0">
              <button mat-button color="primary" [routerLink]="item.route">
                {{item.displayName}}
 
              </button>
            </span> 
            </span> 
 
 
 
 
 
        </div>
 
        <button mat-raised-button class="navbar-toggler" type="button" (click)="sidebarToggle()">
            <span class="sr-only">Toggle navigation</span>
            <span class="navbar-toggler-icon icon-bar"></span>
            <span class="navbar-toggler-icon icon-bar"></span>
            <span class="navbar-toggler-icon icon-bar"></span>
        </button>
        <div class="collapse navbar-collapse justify-content-end" id="navigation">
           <!-- <form class="navbar-form">
                <div class="input-group no-border">
                    <input type="text" value="" class="form-control" placeholder="Search...">
                    <button mat-raised-button type="submit" class="btn btn-white btn-round btn-just-icon">
                        <i class="material-icons">search</i>
                        <div class="ripple-container"></div>
                    </button>
                </div>
            </form> -->
 
 
 
 
 
            <ul class="navbar-nav">
               <!-- <li class="nav-item">
                    <a class="nav-link" href="javascript:void(0)">
                        <i class="material-icons">dashboard</i>
                        <p>
                            <span class="d-lg-none d-md-block">Stats</span>
                        </p>
                    </a>
                </li> -->
 
 
 
 
                <li class="nav-item dropdown">
                    <a class="nav-link" href="javascript:void(0)" id="navbarDropdownMenuLink" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
                        <i class="material-icons">notifications</i>
                        <span class="notification">5</span>
                        <p>
                            <span class="d-lg-none d-md-block">Some Actions</span>
                        </p>
                    </a>
                    <div class="dropdown-menu dropdown-menu-right" aria-labelledby="navbarDropdownMenuLink">
                        <a class="dropdown-item" href="javascript:void(0)">Mike John responded to your email</a>
                        <a class="dropdown-item" href="javascript:void(0)">You have 5 new tasks</a>
                        <a class="dropdown-item" href="javascript:void(0)">You're now friend with Andrew</a>
                        <a class="dropdown-item" href="javascript:void(0)">Another Notification</a>
                        <a class="dropdown-item" href="javascript:void(0)">Another One</a>
                    </div>
                </li>
                <li class="nav-item">
                    <a class="nav-link" href="javascript:void(0)">
                        <i class="material-icons">power_settings_new</i>
                       <!-- <p>
                            <span class="d-lg-none d-md-block">Account</span>
                        </p> -->
                    </a>
                </li>
            </ul>
        </div>
    </div>
 
 
 
 
 
 
</nav>
 
 
 
<!--
 
<nav class="navbar navbar-transparent navbar-absolute">
    <div class="container-fluid">
        <div class="navbar-header">
            <button mat-raised-button type="button" class="navbar-toggle" data-toggle="collapse" (click)="sidebarToggle()">
                <span class="sr-only">Toggle navigation</span>
                <span class="icon-bar"></span>
                <span class="icon-bar"></span>
                <span class="icon-bar"></span>
            </button>
            <a class="navbar-brand" href="javascript:void(0)">{{getTitle()}}</a>
        </div>
        <div class="collapse navbar-collapse">
            <ul class="nav navbar-nav navbar-right">
                <li>
                    <a href="javascript:void(0)" class="dropdown-toggle" data-toggle="dropdown">
                        <i class="material-icons">dashboard</i>
                        <p class="hidden-lg hidden-md">Dashboard</p>
                    </a>
                </li>
                <li class="dropdown">
                    <a href="javascript:void(0)" class="dropdown-toggle" data-toggle="dropdown">
                        <i class="material-icons">notifications</i>
                        <span class="notification">5</span>
                        <p class="hidden-lg hidden-md">Notifications</p>
                    </a>
                    <ul class="dropdown-menu">
                        <li><a href="javascript:void(0)">Mike John responded to your email</a></li>
                        <li><a href="javascript:void(0)">You have 5 new tasks</a></li>
                        <li><a href="javascript:void(0)">You're now friend with Andrew</a></li>
                        <li><a href="javascript:void(0)">Another Notification</a></li>
                        <li><a href="javascript:void(0)">Another One</a></li>
                    </ul>
                </li>
                <li>
                    <a href="javascript:void(0)" class="dropdown-toggle" data-toggle="dropdown">
                       <i class="material-icons">person</i>
                       <p class="hidden-lg hidden-md">Profile</p>
                    </a>
                </li>
            </ul>
 
            <form class="navbar-form navbar-right" role="search">
                <div class="form-group form-black is-empty">
                    <input type="text" class="form-control" placeholder="Search">
                    <span class="material-input"></span>
                </div>
                <button mat-raised-button type="submit" class="btn btn-white btn-round btn-just-icon">
                    <i class="material-icons">search</i><div class="ripple-container"></div>
                </button>
            </form>
        </div>
    </div>
</nav> -->

Toute aide serait appréciée.
Merci d'avance.

https://github.com/RvNirmal/AngularDashboard

https://github.com/ashishahuja1/Dashboard

Les exemples fournis présentent un menu dont le contenu est statique et qui peut être caché. Mais j'ai voulu dire par menu dynamique que le contenu du menu n'est pas codé en dur dans le template et peut être lit à partir d'une source externe. Mon but final est de lire les éléments du menu dynamiquement à partir de la base de données selon les droits de l'utilisateur.

Merci de votre aide.

Code:

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            <!----<a class="navbar-brand" href="javascript:void(0)">{{getTitle()}}</a> -->
         <span *ngFor="let item of navItems"> 
 
            <!-- Handle branch node buttons here -->
          <span *ngIf="item.children && item.children.length > 0">

la balise span est il de trop ? pour voir !

Code:

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<span *ngFor="let item of navItems"> 
   ...

remplace span par <ng-container>.............</ng-container>.

Le problème persiste encore.

peux tu me mettre l'exemple d'un menu sans les ngfor, juste le code brut

Le problème est au niveau du matMenuTriggerFor qui fait appel au sous menu dynamique. Dans le console il ya l'erreur "Error: matMenuTriggerFor: must pass in an mat-menu instance"
En plus pas de problème lorsque j'utilise un sous menu statique
Code:

1 2 3 4 5 <mat-menu #appMenu="matMenu"> <button mat-menu-item>Settings</button> <button mat-menu-item>Help</button> </mat-menu>
au lieu du sous menu dynamique
Code:

1 2 <app-menu-item1 #menu [items]="item.children" ></app-menu-item1>
Donc, comme si le "menu.childMenu" appelé initiallement par "matMenuTriggerFor" n'est pas considéré comme un matMenu.

faut me monter le .html de <app-menu-item1

histoire de voir de quoi il est constitué

c'est le composant menu-item:

Code:

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// menu-item.component.ts
 
import {Component, Input, OnInit, ViewChild} from '@angular/core';
import {Router} from '@angular/router';
import {NavItem} from '../nav-item';
import { MatMenu } from '@angular/material/menu';
 
 
@Component({
  selector: 'app-menu-item1',
  templateUrl: './menu-item.component.html',
  styleUrls: ['./menu-item.component.css']
})
export class MenuItemComponent implements OnInit {
 
  @Input() items: NavItem[];
  @ViewChild('childMenu') public childMenu: MatMenu;
 
  constructor(public router: Router) { }
 
  ngOnInit(): void {
  }
 
}

Code:

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<!--menu-item.html-->
 
<mat-menu #childMenu="matMenu" [overlapTrigger]="false">
  <ng-container *ngFor="let child of items">
    <!-- Handle branch node menu items -->
    <ng-container *ngIf="child.children && child.children.length > 0">
 
      <button mat-menu-item color="primary" [matMenuTriggerFor]="menu.childMenu">
        <mat-icon>{{child.iconName}}</mat-icon>
        <span>{{child.displayName}}</span>
      </button>
 
      <app-menu-item1 #menu [items]="child.children"></app-menu-item1>
 
      <mat-menu #appMenu="matMenu">
        <button mat-menu-item>Settings</button>
        <button mat-menu-item>Help</button>
      </mat-menu>
 
 
    </ng-container>
    <!-- Handle leaf node menu items -->
    <ng-container *ngIf="!child.children || child.children.length === 0">
      <button mat-menu-item [routerLink]="child.route">
        <mat-icon>{{child.iconName}}</mat-icon>
        <span>{{child.displayName}}</span>
      </button>
    </ng-container>
  </ng-container>
</mat-menu>

Mon problème est résolu en mettant le metadata static du ViewChild à la valeur "true" comme suit:
Code:

1 2 @ViewChild('childMenu', {static: true}) public childMenu: MatMenu;
Merci de votre support.