Description

When defining a DropdownButton a custom icon can be specified, meaning that the default dropdown arrow no longer has to be used. Any icon can be provided to the DropdownButton as an argument.

Additionally a property called iconImage was added that allows an image to be specified for the dropdown arrow instead of an icon. This allows for more flexibility when designing forms.

If no icon or iconImage is specified, the DropdownButton defaults to the normal dropdown arrow.

Related Issues

#20686

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