Merge pull request #4494 from pv/auxpanel-scrolling-persisted

Prevent PersistedElements overflowing scrolled areas
matrix-org · May 19, 2020 · b96c1ad · b96c1ad
2 parents 5a1bf03 + d690d4b
commit b96c1ad
Show file tree

Hide file tree

Showing 3 changed files with 70 additions and 3 deletions.
diff --git a/res/css/views/rooms/_AppsDrawer.scss b/res/css/views/rooms/_AppsDrawer.scss
@@ -96,6 +96,10 @@ $AppsDrawerBodyHeight: 273px;
     height: $AppsDrawerBodyHeight;
 }
 
+.mx_AppTile_persistedWrapper > div {
+    height: 100%;
+}
+
 .mx_AppTile_mini .mx_AppTile_persistedWrapper {
     height: 114px;
 }

diff --git a/src/components/views/elements/PersistedElement.js b/src/components/views/elements/PersistedElement.js
@@ -156,16 +156,70 @@ export default class PersistedElement extends React.Component {
         child.style.display = visible ? 'block' : 'none';
     }
 
+    /*
+     * Clip element bounding rectangle to that of the parent elements.
+     * This is not a full visibility check, but prevents the persisted
+     * element from overflowing parent containers when inside a scrolled
+     * area.
+     */
+    _getClippedBoundingClientRect(element) {
+        let parentElement = element.parentElement;
+        let rect = element.getBoundingClientRect();
+
+        rect = new DOMRect(rect.left, rect.top, rect.width, rect.height);
+
+        while (parentElement) {
+            const parentRect = parentElement.getBoundingClientRect();
+
+            if (parentRect.left > rect.left) {
+                rect.width = rect.width - (parentRect.left - rect.left);
+                rect.x = parentRect.x;
+            }
+
+            if (parentRect.top > rect.top) {
+                rect.height = rect.height - (parentRect.top - rect.top);
+                rect.y = parentRect.y;
+            }
+
+            if (parentRect.right < rect.right) {
+                rect.width = rect.width - (rect.right - parentRect.right);
+            }
+
+            if (parentRect.bottom < rect.bottom) {
+                rect.height = rect.height - (rect.bottom - parentRect.bottom);
+            }
+
+            parentElement = parentElement.parentElement;
+        }
+
+        if (rect.width < 0) rect.width = 0;
+        if (rect.height < 0) rect.height = 0;
+
+        return rect;
+    }
+
     updateChildPosition(child, parent) {
         if (!child || !parent) return;
 
         const parentRect = parent.getBoundingClientRect();
+        const clipRect = this._getClippedBoundingClientRect(parent);
+
+        Object.assign(child.parentElement.style, {
+            position: 'absolute',
+            top: clipRect.top + 'px',
+            left: clipRect.left + 'px',
+            width: clipRect.width + 'px',
+            height: clipRect.height + 'px',
+            overflow: "hidden",
+        });
+
         Object.assign(child.style, {
             position: 'absolute',
-            top: parentRect.top + 'px',
-            left: parentRect.left + 'px',
+            top: (parentRect.top - clipRect.top) + 'px',
+            left: (parentRect.left - clipRect.left) + 'px',
             width: parentRect.width + 'px',
             height: parentRect.height + 'px',
+            overflow: "hidden",
         });
     }
 

diff --git a/src/components/views/rooms/AuxPanel.js b/src/components/views/rooms/AuxPanel.js
@@ -141,6 +141,15 @@ export default createReactClass({
         return counters;
     },
 
+    _onScroll: function(rect) {
+        if (this.props.onResize) {
+            this.props.onResize();
+        }
+
+        /* Force refresh of PersistedElements which may be partially hidden */
+        window.dispatchEvent(new Event('resize'));
+    },
+
     render: function() {
         const CallView = sdk.getComponent("voip.CallView");
         const TintableSvg = sdk.getComponent("elements.TintableSvg");
@@ -265,7 +274,7 @@ export default createReactClass({
         }
 
         return (
-            <AutoHideScrollbar className={classes} style={style} >
+            <AutoHideScrollbar className={classes} style={style} onScroll={this._onScroll}>
                 { stateViews }
                 { appsDrawer }
                 { fileDropTarget }