Update README.md

README.md

@@ -1,6 +1,8 @@
 # Animated Tri State Checkbox
 3 State Checkbox for **Android** in pure Material Style, with animation between the states.
 
+<img src="./art/checkbox.gif" width="360" height="740" />
+
 # Usage
 
 In your layout:
@@ -107,4 +109,4 @@ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.
+SOFTWARE.