Dropdown with dataKey attribute throws console errors.

[functionportal]

I'm submitting a ... (check one with "x")
[ X] bug report
[ ] feature request

Current behavior
Dropdown component when using dataKey attribute throws the following error in the console:

Warning: Encountered two children with the same key, null. Keys should be unique so that components maintain their identity across updates. Non-unique keys may cause children to be duplicated and/or omitted — the behavior is unsupported and could change in a future version.
in select (created by Dropdown)
in div (created by Dropdown)
in div (created by Dropdown)

Expected behavior
No errors.

[djapal]

Happens to me too. It seems like property cannot be resolved correctly.
I think the problem is in line 606 of Dropdown.js

    return this.props.dataKey ? ObjectUtils.resolveFieldData(option.value, this.props.dataKey) : this.getOptionLabel(option);

It shouldn't search for option.value but just option.

[mertsincan]

I couldn't replicate it. Could you please attach a plunker or codesandbox link for us to replicate? You can use https://codesandbox.io/s/qjx332qq4 for the sample.

My example code;

const cars = [
            {label: 'Audi', value: {val:'Audi', key: 1}},
            {label: 'BMW', value: {val:'BMW', key: 2}},
            {label: 'Fiat', value: {val:'Fiat', key: 3}},
            {label: 'Honda', value: {val:'Honda', key:4}},
            {label: 'Jaguar', value: {val:'Jaguar', key:5}}
        ];
...

<Dropdown value={this.state.car2} options={cars} dataKey="key" .../>
<div style={{marginTop: '.5em'}}>{this.state.car2 ? 'Selected Car: ' + this.state.car2.val : 'No car selected'}</div>

[djapal]

mertsincan, you assume that the list of objects passed to Dropdown will have a "value" property but this is restricting. I have used my own property as dataKey which cannot be recognized since code is searching for "value" property. I would suggest that if value property is not found, then use the option itself. Try your own example but instead of value use value1. it will log the exception.