Preheat the grill to medium-high heat. If using wooden skewers, soak them in water for at least 30 minutes to prevent burning.
In a large bowl, combine the chicken, pineapple, red bell pepper, green bell pepper, and red onion.
In a separate small bowl, mix the barbecue sauce, olive oil, garlic powder, onion powder, salt, and pepper. Pour this mixture over the chicken and vegetables, tossing to coat evenly.
Thread the chicken, pineapple, and vegetables onto the skewers, alternating between each ingredient.
Place the skewers on the preheated grill and cook for 10-15 minutes, turning occasionally, until the chicken is cooked through and has nice grill marks. The internal temperature of the chicken should reach 165°F.
Remove the kabobs from the grill and let them rest for a few minutes before serving.