Ways to invoke foo specifically when either a click event or a focus event is triggered

Question

Ways to invoke foo specifically when either a click event or a focus event is triggered

In my custom directive, I am binding focus and click events to an element:

app.directive('mydirective', function () {
  return {
    link: function ($scope, $element, $attrs) {
      $element.bind('click focus', function (e) {
        foo(e);
      });
    }
  };
});

I want the function foo to be called only once when either the focus or click event is triggered. However, on clicking the element, both the focus and click events fire, causing foo to be called twice. Is there a way to prevent foo from being called the second time?

Edit: I realize now that mixing hover with click and focus was not a good idea. Thank you all for your input.

javascript angularjs angularjs-directive

Answer 1

Answer №1

To prevent multiple events from firing, you can debounce the events so that only the first event triggers the function.

$element.bind('click focus', function(e) {
    if ( !$(this).data('fired') ) foo(e);

    $(this).data('fired', true);

    setTimeout(function(self) {
        $(self).data('fired', false);
    }, 200, this);

});

Check out the JSFIDDLE demo here

Answer 2

To prevent multiple events from firing, you can debounce the events so that only the first event triggers the function.

$element.bind('click focus', function(e) {
    if ( !$(this).data('fired') ) foo(e);

    $(this).data('fired', true);

    setTimeout(function(self) {
        $(self).data('fired', false);
    }, 200, this);

});

Check out the JSFIDDLE demo here

Answer 3

Answer №2

Here is an alternative implementation of the debounce function:

link: function($scope, $element, $attrs) {

    var executeOnce = (function() {
        var timer;
        return function(event, callback) {
            clearTimeout(timer);
            timer = setTimeout(function() {
                callback.call(self, event);
            }.bind(this), 200); 
         };
    })();

    $element.bind('click focus mouseover', function(event) {
        executeOnce.call(this, event, bar);
    });
}

Check out the demo: http://plnkr.co/edit/AbcdefgUcHijkLmnoPqr?p=preview

Answer 4

Here is an alternative implementation of the debounce function:

link: function($scope, $element, $attrs) {

    var executeOnce = (function() {
        var timer;
        return function(event, callback) {
            clearTimeout(timer);
            timer = setTimeout(function() {
                callback.call(self, event);
            }.bind(this), 200); 
         };
    })();

    $element.bind('click focus mouseover', function(event) {
        executeOnce.call(this, event, bar);
    });
}

Check out the demo: http://plnkr.co/edit/AbcdefgUcHijkLmnoPqr?p=preview

Answer 5

Answer №3

If you want to ensure that the function foo() is called both on click and focus events, it is recommended to use the focus event alone. This is because the click event may not fire independently but will also trigger the element to be focused.
In cases where the element is not an input, opting for the click event alone instead of focus can be a suitable solution.
If you are experiencing the issue of the event being fired three times, it could be due to either the click event firing twice and the focus event once, or vice versa. To address this, you can incorporate e.preventDefault(); in both your click and focus event handlers.
```
app.directive('mydirective', function () {
  return {
    link: function ($scope, $element, $attrs) {
      $element.bind('click', function (e) {
        e.preventDefault();
        foo(e);
      });
    }
  };
});
```
Implementing this technique ensures that the same event callback is not executed multiple times.

Alternatively, a straightforward approach would be to determine whether the element is an input and then bind the appropriate event handler - focus for input elements, and click for other types of elements.

app.directive('mydirective', function () {
  return {
    link: function ($scope, $element, $attrs) {

        if(element is input)
        {    
              $element.bind('focus', function (e) {
                e.preventDefault();
                foo(e);
              });
        }
        else
        {       
              $element.bind('click', function (e) {
                e.preventDefault();
                foo(e);
              });
        }
    }
  };
});

Answer 6

If you want to ensure that the function foo() is called both on click and focus events, it is recommended to use the focus event alone. This is because the click event may not fire independently but will also trigger the element to be focused.
In cases where the element is not an input, opting for the click event alone instead of focus can be a suitable solution.
If you are experiencing the issue of the event being fired three times, it could be due to either the click event firing twice and the focus event once, or vice versa. To address this, you can incorporate e.preventDefault(); in both your click and focus event handlers.
```
app.directive('mydirective', function () {
  return {
    link: function ($scope, $element, $attrs) {
      $element.bind('click', function (e) {
        e.preventDefault();
        foo(e);
      });
    }
  };
});
```
Implementing this technique ensures that the same event callback is not executed multiple times.

Alternatively, a straightforward approach would be to determine whether the element is an input and then bind the appropriate event handler - focus for input elements, and click for other types of elements.

app.directive('mydirective', function () {
  return {
    link: function ($scope, $element, $attrs) {

        if(element is input)
        {    
              $element.bind('focus', function (e) {
                e.preventDefault();
                foo(e);
              });
        }
        else
        {       
              $element.bind('click', function (e) {
                e.preventDefault();
                foo(e);
              });
        }
    }
  };
});

Ways to invoke foo specifically when either a click event or a focus event is triggered

Answer №1

Answer №2

Check out the demo: http://plnkr.co/edit/AbcdefgUcHijkLmnoPqr?p=preview

Answer №3

Similar questions

Could not locate the provider: $stateProvider

Dividing a pair of CSS stylesheets on a single HTML page

Trigger the select dropdown when a key is clicked

Passing methods from child to parent components in Vue2 looped componentsHere is a

Ways to showcase the object on the console

Can you create reusable components in Wordpress that are encapsulated?

Tic-Tac-Toe: The square's value stays unchangeable

Conceal a card once verified within a bootstrap modal upon successful AJAX completion

Storing HTML values in a Meteor database is a common practice for web

The Checkbox handler in Material-UI component fails to update the state - Version 5.0

The MVC 5 view is unable to display an HTML image when adding it within an appended div

Guide to changing an image on a canvas with KineticJS

Using a constructor function in a for loop

Transforming an array in JavaScript into a JSON object

Is it possible for the 'error' attribute to be deemed invalid or inappropriate within ajax?

What is the best way to save a jQuery or JavaScript variable into a JSON file?

Navigating to a specific route upon the arrival of a push notification (Angular, Ionic, ngcordova)

Angularjs failing to navigate to different components

Using Javascript to extract information from the div element

When I utilize the redux connect function, the class information in my IDE (PhpStorm/WebStorm) seems to disappear