Material: select: trackBy does not work with virtual-repeated options

[hollsteinm]

Actual Behavior:

• What is the issue? * Using the ng-model-options= {trackBy: '$value.propertyName'} does not work as expected on initialization or when the scope model changes outside of the mdSelect directive.
• What is the expected behavior? The codepen has a angular only demo right next to the mdSelect bug demo that accurately behaves as expected. The expected behaviour is that providing the ng-model-options= {trackBy: '$value.propertyName'} causes the mdSelect to display the selected value in the select container.

CodePen (or steps to reproduce the issue): *

• CodePen Demo which shows your issue: https://codepen.io/anon/pen/kXoRrR
• Details: On initialization the proper variable is not selected. Classic angular options in select works as expected for an example. Also, applying a new value outside of the select container does not apply the selected value in the select view. Note, that all the values are correct in the background; however, it does not display the correct value unless physically selected in the select container. Note that all these operations are within the same scope.

Angular Versions: *

• Angular Version: 1.5.5 +
• Angular Material Version: 1.0.5, 1.0.9

Additional Information:

• Browser Type: * Chrome, Firefox, Internet Explorer
• Browser Version: * Chrome: 51.0.2704.106 m, IE: 11, FireFox: 47.0
• OS: * Windows 7
• Stack Traces: N/A

[hollsteinm]

Are there any updates for this bug?

[hollsteinm]

Just to make sure I didn't get confused I also tried to have trackBy written as thus:

• {trackBy: 'option.id'}
• {trackBy: option.id}
• {trackBy: '$value.id'} (documented)
• {trackBy: $value.id}
• {trackBy: 'id'}
• {trackBy: id}

All did not work. Also, I know that the last two are not valid, but I tried them anyways.

[hollsteinm]

I updated it because the original issue is slightly off. This behaviour only occurs inside of the mdVirtualRepeatContainer. Removing the md-virtual-repeat-container element dismisses the issue. Although, I have felt this is being ignored either way. I have updated the title accordingly. However, I decided to keep an updated record since the known performance issue workarounds usually suggest using a virtual repeat.

[Splaktar]

Updated the CodePen to AngularJS Material 1.1.21, but ran into the options not displaying due to https://github.com/angular/material/issues/10868.

[Splaktar]

Updated title as md-virtual-repeat does not support trackBy, but md-select does.