reactjs - this.state undefined in a method

I have a custom component that requires access to one of my actual component state (rows).
I defined it in my constructor but when it should be rendered, this.state seems to be always empty, and i dont know why...

The console always displays "undefined this.state".

Here is my code :

export class TableContainer extends React.Component {
    constructor(props : any, context: any) {
        super(props,context);

        this.state = { 
            rows:[ 
                { id: 1, title: 'John', count: 32 },
                { id: 2, title: 'Carl', count: 18 },
                { id: 3, title: 'Mike', count: 25 }
            ]
        };
    }

    rowGetter(i: number) {

        if(this.state) {
            console.log('defined this.state');
            return this.state.rows[i];
        }
        else {
            console.log('undefined this.state');
            return {};
        }
    }


    render() {
        return  (
            

                                    columns={this.state.columns}
                    rowGetter={this.rowGetter}
                    rowsCount={this.state.rows.length}
                    minHeight={500} 
                />
            

        );
    }    
}

I'm new in react so probably it's a little mistake.
I have to precise that rowsCount get the good "this.state.rows.length" in the render function.

Thank you by advance