Microsoft MakeCode

How to make a drop-down parameter? SOLVED

I want to create a function block which has a drop-down parameter as well as normal number entry parameters. For example: Screenshot 2020-09-20 at 16.11.06 - (this screenshot is from an approved “servos” extension).
I can’t figure out what is needed in the TypeScript.

I got it working (lots of trial and error!). Here is a sample JS code snippet:

    enum alarmNum {
//NB this is OUTSIDE the namespace!!!

//% weight=20 color=#b77ff0 icon="\uf017" block="DS3231"
namespace DS3231 {
     * set alarm
     * @param name is the Alarm name
     * @param minute is the Minute that will be set, eg: 13
     * @param second is the Second that will be set, eg: 0
    //% blockId="DS3231_SET_ALARM" block="set alarm %name| minute %minute|second %second"
    //% weight=60 blockGap
    //% parts=DS3231 trackArgs=0
    export function setAlarm(name: alarmNum, minute: number, second: number): void {


The key things:

  • The drop-down list is created in an enum (mine is called “alarmNum”) which is outside the namespace. That’s important!
  • The list is given a name (I used “name”) and is defined in the function’s parameter list as being of type {enum-name} - so: export function setAlarm(name: alarmNum,

I did struggle with the documentation …

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A screenshot of the above example: Screenshot 2020-09-20 at 17.52.38


For what it’s worth, the “playground” is a great resource for seeing a lot of the block alternatives and rapid prototyping: (That’s a tip I picked up from this forum)

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