Drain the canned pineapple, reserving the juice for the dressing. Set pineapple aside.
To prepare dressing, in a small saucepan, combine the pineapple juice, coconut oil, sugar, lemon juice, cornstarch, and water. Bring to a boil, reduce heat, and simmer, stirring until thickened.
Remove from heat and cool completely. When cooled, stir in Greek yogurt. Refrigerate until ready to serve.
For salad: In a large bowl, combine the pineapple, apple, grapes, banana, kiwi, strawberries, blueberries, and orange. Toss together well with the dressing right before serving.