I'm currently working on incorporating a piano layout into my webpage by using two image files: one for white keys and one for black keys.
Although I've managed to create the images, I'm faced with the challenge of arranging the black keys in alternating groups of 2 and 3 while also hiding specific black key images at indices [1, 4(1+3), 8(4+4), 11(8+3), 15(11+4), .., 54]. I am seeking guidance on how to achieve this particular layout.
This is the code snippet I used:
HTML:
<div ng-controller="DrawCtrl as draw">
<ul class="white-keys">
<li ng-repeat="t in draw.range(56) track by $index">
<img ng-src={{draw.white_key}} />
</li>
</ul>
<ul class="black-keys">
<li ng-repeat="t in draw.range(55) track by $index">
<img ng-src={{draw.black_key}} />
</li>
</ul>
</div>
JS:
angular.module('app')
.controller('DrawCtrl', function() {
var self = this;
self.piano_back = 'img/background.png';
self.white_key = 'img/midi_white_up.png';
self.black_key = 'img/midi_black_up.png';
self.range = function(num) {
return new Array(num);
};
});
UPDATE: With the help of hansmaad's solution, I was able to resolve the issue.
HTML:
<ul class="black-keys">
<li ng-repeat="key in draw.keys" ng-switch="key.black">
<img ng-switch-when="true" ng-src={{draw.black_key}} />
<img ng-switch-when="false" ng-src={{draw.black_key}} class="black-hidden" />
</li>
</ul>
JS:
self.keys = [];
var keyGroupOf3 = true;
self.keys.push({black: true}); // first key is shown
var i = 1;
while (i < 54) {
self.keys.push({black: false});
// alwasy followed by at least two
self.keys.push({black: true});
self.keys.push({black: true});
if (keyGroupOf3){
self.keys.push({black: true});
i += 4;
} else {
i += 3;
}