Chop, if you prefer, the pineapple into smaller chunks. Add to a bowl, together with a small splash of syrup from the can.
Slice the cucumber lengthwise, and remove some of the watery flesh with a teaspoon. Then slice both halves lengthwise again (so you have four long quarters) and chop the cucumber in to small pieces.
Slice the spring onion into rings. Use 2 or 3 depending how large the spring onions are.
Add everything to the bowl, together with sambal, vinegar, sugar and salt and give everything a good stir. The salad tastes best when you leave it for about 10 minutes for flavours to really combine.