cancel timer

src/App.vue

@@ -136,7 +136,8 @@
                 <v-col :cols="1">
                 <v-select dense v-model="timer" label="Countdown time" :items="countdownitems"></v-select>
                 </v-col><v-col :cols="1">
-                <v-btn x-small @click="starttimer">Start</v-btn>
+                <v-btn v-if="!showtimer" x-small @click="starttimer">Start</v-btn>
+                <v-btn v-else x-small @click="stoptimer">Stop</v-btn>
                 </v-col><v-col :cols="2">
                 <font-picker dense
                   :api-key="'AIzaSyCAW_4WvUsVuikytJw_yvJKxHKRHrCsBAs'"