You need to declare that your component is using the State interface, it used by Typescript’s Generics.
interface IProps {
}
interface IState {
playOrPause?: string;
}
class Player extends React.Component<IProps, IState> {
// ------------------------------------------^
constructor(props: IProps) {
super(props);
this.state = {
playOrPause: 'Play'
};
}
render() {
return(
<div>
<button
ref={playPause => this.playPause = playPause}
title={this.state.playOrPause} // in this line I get an error
>
Play
</button>
</div>
);
}
}