update history

diff --git a/HISTORY.md b/HISTORY.md
index 79862af88c466691710ddf2a9e24dbcb8b40aec3..9eba41b07a109b9528a354b65552698bad88b864 100644 (file)
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -10,6 +10,7 @@
 - Add `focusOnOpen`.
 - Add `hourStep` `minuteStep` `secondStep`.
 - Fix disabled style.
+- Use `this.xxx` to replace `this.refs.xxx`.
 
 2.4.0 / 2017-05-02
 ---------------------------