How to add modernizr build so that I can properly check Modernizr.capture? (currently always undefined) - input

Question

I need to check if the user's device can input from a camera on my site. To do this I am attempting to use modernizr. I have followed the steps/example code provided on their site but when I test the capture attribute, I always get undefined, regardless of if I am on a device that supports capture.
Steps I followed:
I browsed for the input[capture] attribute and added it to the build
I copied the demo code to check this feature and added it to my project
I downloaded the build, added the js file to my project, and included the appropriate reference in my page
However after all of this, when inspecting Modernizr.capture in the chrome inspector, it always shows up as undefined.
My basic check function is as follows:
$scope.hasCamera = function() {
if (Modernizr.capture) {
// supported
return true;
} else {
// not-supported
return false;
}
}
This is my first time using Modernizr. Am I missing a step or doing something incorrectly? I also installed modernizr using npm install and tried adding the reference to a json config file from the command line.
Alternatively, how might I check if my device has a camera?
Thank you very much for your time. Please let me know if I am being unclear or if you need any additional information from me.

Answer 1

A few things
while photos are helpful, actual code hosted in a public website (either your own project, or on something like jsbin.com) is 10x as useful. As a result, I am not sure why it is coming back as undefined.
The actual capture detect is quite simple. It all comes down to this
var capture = 'capture' in document.createElement('input')`
Your code is a lot more complicated than it needs to be. Lets break it down. You trying to set $scope.hasCamera to equal the result of Modernizr.capture, and you are using a function to check the value of Modernizr.capture, and if it is true, return true. If it is false, return false. There is a fair bit of duplicated logic, so we can break it down from the inside out.
Firstly, your testing for a true/false value, and then returning the same value. That means you could simplify the code by just returning the value of Modernizr.capture
$scope.hasCamera = function() {
return Modernizr.capture
}
While Modernizr will always be giving you a boolean value (when it is functioning - without seeing your actual code I can't say why it is coming back as undefined), if you are unsure of the value you can add !! before it to coerce it into a boolean. In your case, it would make undefined into false
$scope.hasCamera = function() {
return !!Modernizr.capture
}
At this point, you can see that we are setting up a function just to return a static value. That means we can just set assign that static value directly to the variable rather than setting up a function to do that
$scope.hasCamera = !!Modernizr.capture
Now, the final thing you may be able to do something better is if you are only using Modernizr for this one feature. Since it is such a simple feature detection, it is overkill to be using all of Modernizr.
$scope.hasCamera = 'capture' in document.createElement('input')`