Bootstrap Modals

Controllers and Templates Everywhere!

Most of the Bootstrap directives are straightforward, but the modals provide challenges relating to scope, controllers, and service injection.

We'll start off by creating a template for the modal content.

In views/modal.html:

<div>
  <div class="modal-header">
    <button type="button" class="close" ng-click="close()">&times;</button>
    <h4 class="modal-title">Welcome to my Modal!</h4>
  </div>
  <div class="modal-body">

  </div>
  <div class="modal-footer">
    <button type="button" class="btn btn-default" ng-click="close()">Close</button>
    <button type="button" class="btn btn-primary" ng-click="saveChanges()">Save changes</button>
  </div>
</div>

We'll be adding more to the modal's body, so stay tuned.

Now, we need a way to open this modal once a button has been clicked. Let's create a button to do so.

In index.html

<button type="button" class="btn btn-default" ng-click="open()">Open the modal!</button>

Now in order to open the modal, we're going to do the following:

1. Create a function called open in the Angular application.
2. Inject a dependency for utilizing modals.
3. Create another controller specifically for the modal instance.

In js/app.js

app.controller('BootstrapCtrl', ['$scope', '$uibModal', function($scope, $uibModal) {
  $scope.navCollapsed = true;

  $scope.open = function() {
    $uibModal.open({
      animation: true,
      templateUrl: '/views/modal.html',
      controller: 'ModalInstanceCtrl'
    });
  };
}]);

app.controller('ModalInstanceCtrl', ['$scope', '$uibModalInstance', function($scope, $uibModalInstance) {
  $scope.close = function() {
    $uibModalInstance.dismiss('close');
  };

  $scope.saveChanges = function() {
    $uibModalInstance.dismiss('close');
  };
}]);

So let's breakdown what all this code implements.

• In order to open a modal, we need to inject a component called a service into our controller. In this case, Bootstrap UI provides a service called $uibModal.
  • This service provides functions for modals
• We can call $uibModal.open to open a new modal instance with parameters. We have to specify the location of the template and the controller used for the modal instance
• The controller ModalInstanceCtrl provides a controller specifically for a modal instance. The $scope in this controller is separate from the scope of the controller that called it.
  • $uibModalInstance represents the modal instance, and we can call functions like dismiss and close in order to perform operations on the instance.

Passing Data between Controllers

We may have an instance where data needs to be passed from the main controller to the modal instance controller. In that case, the Bootstrap UI modal service provides some functionality to pass data back and forth.

• Including a resolve object to the modal instance serves as a "gateway" for passing data to the modal controller
  • Once data is passed into the object, it can be accessed by including it as a dependency in the controller
  • Attach the data from the dependency to the controller's $scope
• Data can be passed back to the main controller by passing it as an argument to the $uibModalInstance.close function
  • Once the data is passed, it can be accessed in the main controller through result, a promise.

The Final Code

js/app.js

var app = angular.module('BootstrapApp', ['ngAnimate', 'ui.bootstrap']);

app.controller('BootstrapCtrl', ['$scope', '$uibModal', function($scope, $uibModal) {
  $scope.navCollapsed = true;
  $scope.selectedItem = '';

  $scope.open = function() {
    var modalInstance = $uibModal.open({
      animation: true,
      templateUrl: '/views/modal.html',
      controller: 'ModalInstanceCtrl',
      resolve: {
        items: function() {
          return ['Larry', 'Curly', 'Moe'];
        }
      }
    });

    modalInstance.result.then(function(selectedItem) {
      $scope.selectedItem = selectedItem;
    });
  };
}]);

app.controller('ModalInstanceCtrl', ['$scope', '$uibModalInstance', 'items', function($scope, $uibModalInstance, items) {
  $scope.items = items;
  $scope.selectedItem = items[0];
  $scope.selectItem = function(item) {
    $scope.selectedItem = item;
  }

  $scope.close = function() {
    $uibModalInstance.dismiss('close');
  };

  $scope.saveChanges = function() {
    $uibModalInstance.close($scope.selectedItem);
  };
}]);

views/modal.html

<div>
  <div class="modal-header">
    <button type="button" class="close" ng-click="close()">&times;</button>
    <h4 class="modal-title">Welcome to my Modal!</h4>
  </div>
  <div class="modal-body">
    <button class="btn btn-primary" ng-repeat="item in items" ng-click="selectItem(item)">{{item}}</button>
    <div>
      Selected Item: {{selectedItem}}
    </div>
  </div>
  <div class="modal-footer">
    <button type="button" class="btn btn-default" ng-click="close()">Close</button>
    <button type="button" class="btn btn-primary" ng-click="saveChanges()">Save changes</button>
  </div>
</div>

index.html

<div ng-include="'/views/navbar.html'"></div>
<button type="button" class="btn btn-default" ng-click="open()">Open the modal!</button>
{{ selectedItem }}