[objective-c] How do I create a basic UIButton programmatically?

This is an example as well to create three buttons. Just move their location.

UIImage *buttonOff = [UIImage imageNamed:@"crysBallNorm.png"];
UIImage *buttonOn = [UIImage imageNamed:@"crysBallHigh.png"];

UIButton *predictButton = [UIButton alloc];
predictButton = [UIButton buttonWithType:UIButtonTypeCustom];
predictButton.frame = CGRectMake(180.0, 510.0, 120.0, 30.0);
[predictButton setBackgroundImage:buttonOff forState:UIControlStateNormal];
[predictButton setBackgroundImage:buttonOn forState:UIControlStateHighlighted];
[predictButton setTitle:@"Predict" forState:UIControlStateNormal];
[predictButton setTitleColor:[UIColor purpleColor] forState:UIControlStateNormal];
[predictButton addTarget:self action:@selector(buttonPressed:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:predictButton];