1 files changed, 52 insertions, 0 deletions

diff --git a/viewer/src/services/dragscrollclickfix.ts b/viewer/src/services/dragscrollclickfix.ts
new file mode 100644
index 0000000..38eb106
--- /dev/null
+++ b/viewer/src/services/dragscrollclickfix.ts
@@ -0,0 +1,52 @@
+/* ldgallery - A static generator which turns a collection of tagged
+--             pictures into a searchable web gallery.
+--
+-- Copyright (C) 2019-2020  Guillaume FOUET
+--
+-- This program is free software: you can redistribute it and/or modify
+-- it under the terms of the GNU Affero General Public License as
+-- published by the Free Software Foundation, either version 3 of the
+-- License, or (at your option) any later version.
+--
+-- This program is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+-- GNU Affero General Public License for more details.
+--
+-- You should have received a copy of the GNU Affero General Public License
+-- along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+// https://github.com/donmbelembe/vue-dragscroll/issues/61
+export default class DragScrollClickFix {
+
+  readonly DRAG_DELAY = 250; // This is the minimal delay to consider a click to be a drag, mostly usefull for touch devices
+
+  timer: NodeJS.Timeout | null = null;
+  dragging: boolean = false;
+
+  onDragScrollStart() {
+    this.timer = setTimeout(() => this.onTimer(), this.DRAG_DELAY);
+  }
+
+  onTimer() {
+    this.timer = null;
+    this.dragging = true;
+  }
+
+  onDragScrollEnd() {
+    if (this.timer) {
+      clearTimeout(this.timer);
+      this.timer = null;
+    }
+    setTimeout(() => this.dragging = false);
+  }
+
+  onClickCapture(e: MouseEvent) {
+    if (this.dragging) {
+      this.dragging = false;
+      e.preventDefault();
+      e.stopPropagation();
+    }
+  }
+}