React Checkbox not sending onChange
TLDR: Use defaultChecked instead of checked, working jsbin.
Trying to setup a simple checkbox that will cross out its label text when it is checked. For some reason handleChange is not getting fired when I use the component. Can anyone explain what I'm doing wrong?
var CrossoutCheckbox = React.createClass({
getInitialState: function () {
return {
complete: (!!this.props.complete) || false
};
},
handleChange: function(){
console.log('handleChange', this.refs.complete.checked); // Never gets logged
this.setState({
complete: this.refs.complete.checked
});
},
render: function(){
var labelStyle={
'text-decoration': this.state.complete?'line-through':''
};
return (
<span>
<label style={labelStyle}>
<input
type="checkbox"
checked={this.state.complete}
ref="complete"
onChange={this.handleChange}
/>
{this.props.text}
</label>
</span>
);
}
});
Usage:
React.renderComponent(CrossoutCheckbox({text: "Text Text", complete: false}), mountNode);
Solution:
Using checked doesn't let the underlying value change (apparently) and thus doesn't call the onChange handler. Switching to defaultChecked seems to fix this:
var CrossoutCheckbox = React.createClass({
getInitialState: function () {
return {
complete: (!!this.props.complete) || false
};
},
handleChange: function(){
this.setState({
complete: !this.state.complete
});
},
render: function(){
var labelStyle={
'text-decoration': this.state.complete?'line-through':''
};
return (
<span>
<label style={labelStyle}>
<input
type="checkbox"
defaultChecked={this.state.complete}
ref="complete"
onChange={this.handleChange}
/>
{this.props.text}
</label>
</span>
);
}
});
Solution 1:
To get the checked state of your checkbox the path would be:
this.refs.complete.state.checked
The alternative is to get it from the event passed into the handleChange
method:
event.target.checked
Solution 2:
It's better not to use refs in such cases. Use:
<input
type="checkbox"
checked={this.state.active}
onClick={this.handleClick}
/>
There are some options:
checked
vs defaultChecked
The former would respond to both state changes and clicks. The latter would ignore state changes.
onClick
vs onChange
The former would always trigger on clicks.
The latter would not trigger on clicks if checked
attribute is present on input
element.
Solution 3:
If you have a handleChange
function that looks like this:
handleChange = (e) => {
this.setState({
[e.target.name]: e.target.value,
});
}
You can create a custom onChange
function so that it acts like an text input would:
<input
type="checkbox"
name="check"
checked={this.state.check}
onChange={(e) => {
this.handleChange({
target: {
name: e.target.name,
value: e.target.checked,
},
});
}}
/>
Solution 4:
In the scenario you would NOT like to use the onChange handler on the input DOM, you can use the onClick
property as an alternative. The defaultChecked
, the condition may leave a fixed state for v16 IINM.
class CrossOutCheckbox extends Component {
constructor(init){
super(init);
this.handleChange = this.handleChange.bind(this);
}
handleChange({target}){
if (target.checked){
target.removeAttribute('checked');
target.parentNode.style.textDecoration = "";
} else {
target.setAttribute('checked', true);
target.parentNode.style.textDecoration = "line-through";
}
}
render(){
return (
<span>
<label style={{textDecoration: this.props.complete?"line-through":""}}>
<input type="checkbox"
onClick={this.handleChange}
defaultChecked={this.props.complete}
/>
</label>
{this.props.text}
</span>
)
}
}
I hope this helps someone in the future.
Solution 5:
In case someone is looking for a universal event handler the following code can be used more or less (assuming that name property is set for every input):
this.handleInputChange = (e) => {
item[e.target.name] = e.target.type === "checkbox" ? e.target.checked : e.target.value;
}