Refreshing children state from parent React

Question

I have a table with some data and each element in the table is a React class component. It looks like this:

All i want is to have one checkbox for "check all" feature (top left checkbox). The thing is I don't know how to solve that because of props and state.

I have code like that in single element component:

getInitialState: function() {
    return { component: this.props.data };
  },

render: function() {
    var data = this.state.component;
    data = data.set('checked', this.props.data.get('checked'));
    ...
}

And I know I shouldn't get checked param from props but it is just temporary.

What I have problem with is: When I update checked param in parent it doesn't update state, because getInitialState isn't called after refresh (yep, i know it should be like that).

My question is: can I somehow update state of child component? Or it is better way to achieve that.

Answer 1

My approach is that you should have structure something like this in parent's render:

<ParentView>
{ this.props.rows.map(function(row) {
    <ChildRow props={row.props} />
  }).bind(this)
}
</ParentView>

And then on row.props you have the information whether current row item is checked or not. When parent checkbox is toggled, you populate all the row.props with the status.

On child, you will receive those with componentWillReceiveProps and you do the magic (e.g. set the correct state) when checkbox is toggled:

componentWillReceiveProps: function(props) {
  this.setState({isChecked: props.isChecked});
}

(Info from the React's docs: Calling this.setState() within this function will not trigger an additional render.)

Child element's render would be something like:

<div>
  <input type='checkbox' checked={this.state.isChecked} />
  <label>{this.props.label}</label>
</div>