React Native slice() function undefined error - react-native

Question

I want to update my listview row for that I am trying to slice listview datasource but its raising below error:
this.state.dataSource.slice is not a function. (In
'this.state.dataSource.slice()', 'this.state.dataSource.slice' is
undefined)
And here is my code:
let newArray = this.state.dataSource.slice();
newArray[indexToUpdate] = {
//Here I am updating my values.
};
this.setState({
dataSource: this.state.dataSource.cloneWithRows(newArray),
});
Let me know if there is any error in my code or something wrong I have done.

Answer 1

this.state.dataSource is not an Array, that's why you cant do slice() on dataSource. It looks like this
{ _rowHasChanged: [Function: rowHasChanged],
_getRowData: [Function: defaultGetRowData],
_sectionHeaderHasChanged: [Function],
_getSectionHeaderData: [Function: defaultGetSectionHeaderData],
_dataBlob: { s1: [ 'row 1', 'row 2' ] },
_dirtyRows: [ [ true, true ] ],
_dirtySections: [ true ],
_cachedRowCount: 2,
rowIdentities: [ [ '0', '1' ] ],
sectionIdentities: [ 's1' ]
}
Your required array is in _dataBlob key of that object.
Note: it's working fine and updates listview dataSource using below line
this.state.dataSource._dataBlob.s1.slice()