Calculate the amount of px an element (height) is in viewport Fiddle demo This tiny function will return the amount of px an element is visible in the (vertical) Viewport: function inViewport($el) { var elH = $el.outerHeight(), H = $(window).height(), r = $el[0].getBoundingClientRect(), t=r.top, b=r.bottom; return Math.max(0, t>0? Math.min(elH, H-t) : Math.min(b, H)); } Use … Read more
Although View.getVisibility() does get the visibility, its not a simple true/false. A view can have its visibility set to one of three things. View.VISIBLE The view is visible. View.INVISIBLE The view is invisible, but any spacing it would normally take up will still be used. Its “invisible” View.GONE The view is gone, you can’t see … Read more
Yes, the Visible property is a big deal in Windows Forms, that’s what actually gets the handle created and causes OnLoad() to run. In other words, the window doesn’t exist until it gets visible. And it will ignore attempts to undo this. It is pretty common to want to still create the handle but not … Read more
You can get the rect of a cell with rectForRowAtIndexPath: method and compare it with tableview’s bounds rect using CGRectContainsRect function. Note that this will not instantiate the cell if it is not visible, and thus will be rather fast. Swift let cellRect = tableView.rectForRowAtIndexPath(indexPath) let completelyVisible = tableView.bounds.contains(cellRect) Obj-C CGRect cellRect = [tableView rectForRowAtIndexPath:indexPath]; … Read more
You can write a jQuery function like this to determine if an element is in the viewport. Include this somewhere after jQuery is included: $.fn.isInViewport = function() { var elementTop = $(this).offset().top; var elementBottom = elementTop + $(this).outerHeight(); var viewportTop = $(window).scrollTop(); var viewportBottom = viewportTop + $(window).height(); return elementBottom > viewportTop && elementTop < … Read more
This works: Rect scrollBounds = new Rect(); scrollView.getHitRect(scrollBounds); if (imageView.getLocalVisibleRect(scrollBounds)) { // Any portion of the imageView, even a single pixel, is within the visible window } else { // NONE of the imageView is within the visible window }