67 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
			
		
		
	
	
			67 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
| 
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| class ChapterToggle {
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| 
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|     constructor(elem) {
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|         this.elem = elem;
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|         this.isOpen = elem.classList.contains('open');
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|         elem.addEventListener('click', this.click.bind(this));
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|     }
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| 
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|     open() {
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|         let list = this.elem.parentNode.querySelector('.inset-list');
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| 
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|         this.elem.classList.add('open');
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|         list.style.display = 'block';
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|         list.style.height = '';
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|         let height = list.getBoundingClientRect().height;
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|         list.style.height = '0px';
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|         list.style.overflow = 'hidden';
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|         list.style.transition = 'height ease-in-out 240ms';
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| 
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|         let transitionEndBound = onTransitionEnd.bind(this);
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|         function onTransitionEnd() {
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|             list.style.overflow = '';
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|             list.style.height = '';
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|             list.style.transition = '';
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|             list.removeEventListener('transitionend', transitionEndBound);
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|         }
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| 
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|         setTimeout(() => {
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|             list.style.height = `${height}px`;
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|             list.addEventListener('transitionend', transitionEndBound)
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|         }, 1);
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|     }
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| 
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|     close() {
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|         let list = this.elem.parentNode.querySelector('.inset-list');
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| 
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|         this.elem.classList.remove('open');
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|         list.style.display =  'block';
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|         list.style.height = list.getBoundingClientRect().height + 'px';
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|         list.style.overflow = 'hidden';
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|         list.style.transition = 'height ease-in-out 240ms';
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| 
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|         let transitionEndBound = onTransitionEnd.bind(this);
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|         function onTransitionEnd() {
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|             list.style.overflow = '';
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|             list.style.height = '';
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|             list.style.transition = '';
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|             list.style.display =  'none';
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|             list.removeEventListener('transitionend', transitionEndBound);
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|         }
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| 
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|         setTimeout(() => {
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|             list.style.height = `0px`;
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|             list.addEventListener('transitionend', transitionEndBound)
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|         }, 1);
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|     }
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| 
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|     click(event) {
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|         event.preventDefault();
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|         this.isOpen ?  this.close() : this.open();
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|         this.isOpen = !this.isOpen;
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|     }
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| 
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| }
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| 
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| module.exports = ChapterToggle; |