Fix Issue #2823 - Ugly scrollbars in oembed iframes and broken resizing

- Fix _resizeIframe function, shorten the timeout between calls
- Simplify the oembed iframe generation code and reduce the minimum
iframe height to 200px
- Add smooth CSS transition for iframe resizing

include/oembed.php

@@ -209,25 +209,32 @@ function oembed_format_object($j){
 	return mb_convert_encoding($ret, 'HTML-ENTITIES', mb_detect_encoding($ret));
 }
 
+/**
+ * Generates the iframe HTML for an oembed attachment. Width and height are given
+ * by the remote, and are regularly too small for the generated iframe.
+ *
+ * The width is entirely discarded for the actual width of the post, while fixed
+ * height is used as a starting point before the inevitable resizing.
+ *
+ * Since the iframe is automatically resized on load, there are no need for ugly
+ * and impractical scrollbars.
+ *
+ * @param string $src Original remote URL to embed
+ * @param string $width
+ * @param string $height
+ * @return string
+ *
+ * @see oembed_format_object()
+ */
 function oembed_iframe($src, $width, $height) {
-
-	if(! $width || strstr($width,'%'))
-		$width = '640';
 	if (!$height || strstr($height,'%')) {
-		$height = '300';
+		$height = '200';
-		$resize = 'onload="resizeIframe(this);"';
+	}
-	} else
+	$width = '100%';
-		$resize = '';
-
-	// try and leave some room for the description line.
-	$height = intval($height) + 80;
-	$width  = intval($width) + 40;
 
 	$a = get_app();
-
+	$s = $a->get_baseurl() . '/oembed/'.base64url_encode($src);
-	$s = $a->get_baseurl()."/oembed/".base64url_encode($src);
+	return '<iframe onload="resizeIframe(this);" class="embed_rich" height="' . $height . '" width="' . $width . '" src="' . $s . '" scrolling="no" frameborder="no">' . t('Embedded content') . '</iframe>';
-	return '<iframe '.$resize.' class="embed_rich" height="'.$height.'" width="'.$width.'" src="'.$s.'" frameborder="no">'.t('Embedded content').'</iframe>';
-
 }
 
 

js/main.js

@@ -5,17 +5,14 @@
 
 	function _resizeIframe(obj, desth) {
 		var h = obj.style.height;
-		var ch = obj.contentWindow.document.body.scrollHeight + 'px';
+		var ch = obj.contentWindow.document.body.scrollHeight;
-		if (h==ch) {
+		if (h == (ch + 'px')) {
 			return;
 		}
-		//console.log("_resizeIframe", obj, desth, ch);
+		if (desth == ch && ch>0) {
-		if (desth!=ch) {
+			obj.style.height  = ch + 'px';
-			setTimeout(_resizeIframe, 500, obj, ch);
-		} else {
-			if (ch>0) obj.style.height  = ch;
-			setTimeout(_resizeIframe, 1000, obj, ch);
 		}
+		setTimeout(_resizeIframe, 100, obj, ch);
 	}
 
 	function openClose(theID) {

view/global.css

@@ -115,6 +115,7 @@ span.connector {
 
 .embed_rich {
   display: block;
+  transition: height .75s;
 }
 
 /* Shared Messages */