練習問題8　　

- (IBAction)changeBMI:(id)sender
{
  bmi=[sender floatValue];
  [self calcWeightAndSet];
}
- (IBAction)changeHeight:(id)sender
{
  height=[sender floatValue];
  [self calcBMIAndSet];
}
- (IBAction)changeWeight:(id)sender
{
  weight=[sender floatValue];
  [self calcBMIAndSet];
}

- (void)calcWeightAndSet
{
  weight=calculateWeight(height, bmi);  
  [self setValues];
}
- (void)calcBMIAndSet
{
  bmi=calculateBMI(height, weight);  
  [self setValues];
}

- (void)setValues
{
  [bmiField setFloatValue:bmi];
  [bmiSlider setFloatValue:bmi];
  
  [heightField setFloatValue:height];
  [heightSlider setFloatValue:height];
  
  [weightField setFloatValue:weight];
  [weightSlider setFloatValue:weight];
}