Check out this example on JSFiddle!
<script src="https://unpkg.com/vue"></script>
<div id="app">
<label>
<input
type="checkbox"
name="demo"
:checked="isChecked"
@input="someMeth('A')"
value="A"/>
A
</label>
<label>
<input
type="radio"
name="demo"
:checked="isChecked"
@input="someMeth('B')"
value="B"/>
B
</label>
<div>
{{somedata}}
</div>
</div>
When clicking on the input (checkbox or radio button), its status does not toggle.
The issue could be solved by removing either :checked or @input, but both are necessary in this case.
Alternatively, using @click would yield a similar result.