up

2017-03-12 12:54:13 +03:00 · 2017-03-12 12:54:13 +03:00 · 8360ebbe90
commit 8360ebbe90
parent fc84391bd2
60 changed files with 920 additions and 1672 deletions
--- a/2-ui/3-event-details/5-keyboard-events/2-check-sync-keydown/solution.view/index.html
+++ b/2-ui/3-event-details/5-keyboard-events/2-check-sync-keydown/solution.view/index.html
@ -0,0 +1,47 @@
+<!DOCTYPE HTML>
+<html>
+<body>
+
+  <p>Press "Q" and "W" together (can be in any language).</p>
+
+  <script>
+    function runOnKeys(func, ...codes) {
+      let pressed = new Set();
+
+      document.addEventListener('keydown', function(event) {
+        pressed.add(event.code);
+
+        for (let code of codes) { // are all keys in the set?
+          if (!pressed.has(code)) {
+            return;
+          }
+        }
+
+        // yes, they are
+
+        // during the alert, if the visitor releases the keys,
+        // JavaScript does not get the "keyup" event
+        // and pressed set will keep assuming that the key is pressed
+        // so, to evade "sticky" keys, we reset the status
+        // if the user wants to run the hotkey again - let him press all keys again
+        pressed.clear();
+
+        func();
+      });
+
+      document.addEventListener('keyup', function(event) {
+        pressed.delete(event.code);
+      });
+
+    }
+
+    runOnKeys(
+      () => alert("Hello!"),
+      "KeyQ",
+      "KeyW"
+    );
+  </script>
+
+</body>
+
+</html>