Change-Boom-Buttons-Dynamically.md

+Sometimes you may wanna change the contents, like image, text, etc, on the boom-buttons when they're already boomed out. This feature is not support until version 2.0.9.
+### Change Contents from Builders
+From version 2.0.9, you can change contents in boom-buttons by changing them in builder:
+```
+builder.normalText("Changed!");
+builder.normalTextColor(Color.YELLOW);
+```
+The text and its color will be changed even when the boom-button is boomed. Check [the demo activity](https://github.com/Nightonke/BoomMenu/blob/master/app/src/main/java/com/nightonke/boommenusample/ChangeBoomButtonActivity.java) for more details.
+**But notice**, not every method can do that magic!
+
 You can get the children views of a boom button by the following codes:
 ```
 BoomButton boomButton = bmb.getBoomButton(i);