A flash service and directive for setting and displaying flash messages in Angular JS. Specifically, the flash service is a publisher of flash messages and the flash directive is a subscriber to flash messages. The flash directive leverages the Twitter Bootstrap Alert component.

Download angular-flash.min.js or install with bower.

$ bower install angular-flash --save

Load the angular-flash.service and the angular-flash.flash-alert-directive modules in your app.

angular.module('app', ['angular-flash.service', 'angular-flash.flash-alert-directive']);

angular.module('app', ['angular-flash.service', 'angular-flash.flash-alert-directive'])
        .config(function (flashProvider) {
        
            // Support bootstrap 3.0 "alert-danger" class with error flash types
            flashProvider.errorClassnames.push('alert-danger');

            /**
             * Also have...
             *
             * flashProvider.warnClassnames
             * flashProvider.infoClassnames
             * flashProvider.successClassnames
             */

        })

Use the flash service to publish a flash messages...

var FooController = function(flash){
    // Publish a success flash
    flash.success = 'Do it live!';

    // Publish a error flash
    flash.error = 'Fail!';

    // Publish an info flash to the `alert-1` subscriber
    flash.to('alert-1').info = 'Only for alert 1';

    // The `flash-alert` directive hides itself when if receives falsey flash messages of any type
    flash.error = '';

};

FooController.$inject = ['flash'];

Use the flash-alert directive to subscribe to flash messages...

<!-- Subscribe to success flash messages. -->
<div flash-alert="success" active-class="in" class="alert fade">
    <strong class="alert-heading">Congrats!</strong>
    <span class="alert-message">{{flash.message}}</span>
</div>

<!-- Subscribe to error flash messages. -->
<div flash-alert="error" active-class="in" class="alert fade">
    <strong class="alert-heading">Boo!</strong>
    <span class="alert-message">{{flash.message}}</span>
</div>

<!-- Subscribe to all flash messages. -->
<div flash-alert active-class="in" class="alert fade">
    <strong class="alert-heading">Boo!</strong>
    <span class="alert-message">{{flash.message}}</span>
</div>

<!-- Subscribe to all flash messages sent to `alert-1`. -->
<div id="alert-1" flash-alert active-class="in" class="alert fade">
    <strong class="alert-heading">Boo!</strong>
    <span class="alert-message">{{flash.message}}</span>
</div>

<!-- Set the display duration in milli-secs.  Default is 5000, 0 disables the fade-away. -->
<div flash-alert active-class="in" class="alert fade" duration="0">
    <!-- Manually hide the alert with `hide()` -->
    <button type="button" class="close" ng-click="hide()">&times;</button>
    <strong class="alert-heading">Boo!</strong>
    <span class="alert-message">{{flash.message}}</span>
</div>

When a flash message is published, the flash-alert directive will add a class of the form alert-<type> and also add classes specified in active-class. Then after 5 seconds it will remove them.

The example above leverages Twitter Bootstrap CSS3 transitions: fade and in.

Bootstrap 2 has a few styling quirks with the .alert and .fade classes.

Some folks may want hidden alerts to take up visible space others may not. Fortunately, each case is easy to achieve by declaring .alert as indicated below...

Takes up no visible space when hidden

<div flash-alert active-class="in alert" class="fade">
...
</div>

Takes up visible space when hidden

<div flash-alert active-class="in" class="fade alert">
...
</div>

The .fade class only transitions opacity and the base .alert class has a background color and background border used for alert warnings. Together these styling attributes can make it challenging to achieve smooth transitions.

Fortunately, its easy to replace the .alert class and move the warning colors to .alert-warn as illustrated below...

Styling

/* Remove colors and add transition property */
.alert-flash {
    padding: 8px 35px 8px 14px;
    margin-bottom: 20px;
    text-shadow: 0 1px 0 rgba(255, 255, 255, 0.5);
    border: 1px solid transparent;
    -webkit-border-radius: 4px;
    -moz-border-radius: 4px;
    border-radius: 4px;

    /* change transition property to all */
    -webkit-transition-property: all;
    transition-property: all;
}

.alert-flash h4 {
    margin: 0;
}

.alert-flash .close {
    position: relative;
    top: -2px;
    right: -21px;
    line-height: 20px;
}

/* add warning colors to warn class */
.alert-warn {
    background-color: #fcf8e3;
    border: 1px solid #fbeed5;
}

.alert-warn,
.alert-warn h4 {
    color: #c09853;
}

Template:

<div flash-alert="info" active-class="in" class="alert-flash fade">
    <i class="icon-info-sign"></i>
    <strong class="alert-heading">Ahem...</strong>
    <span class="alert-message">{{flash.message}}</span>
</div>

flashProvider.errorClassnames
flashProvider.warnClassnames
flashProvider.infoClassnames
flashProvider.successClassnames

Set and get flash messages with the following flash properties...

• success
• info
• warn
• error

Register a subscriber callback function to be notified of flash messages. The subscriber function has two arguments: message and type.

Clear all subscribers and flash messages.

The project requires Bower, Grunt, and PhantomJS. Once you have installed them, you can build, test, and run the project.

To build and run tests, run either...

$ make install

or

$ npm install
$ bower install
$ grunt install

To run a live demo or do some hackery, run...

$ grunt server