{
   data:[
      {id:1,type:0...},{id:2,type:0...},{id:3,type:1...},
   ]
}

_keyExtractor = (item,index) => item.id.toString();

<FlatList
   data={this.state.products}
   renderItem={this.renderItem}
   keyExtractor={this._keyExtractor}
   numColumns={3}
/>

numColumns={item.type ? 1 : 2}