Objective-C: Why is my if statement not working? - objective-c

Question

Here i have some code that checks if the iphone has a camera flash. And then check if my switch is on by using this code:
if(switch1.on){
}
The light turns on fine without this code and i have also tried this code as well:
if(!(switch1.on)){
}
and that successfully turns my camera flash on but also turns it on even when the switch is set to off
Here is my full code:
-(IBAction)torchon:(id)sender{
AVCaptureDevice *flashlight = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
if ([flashlight isTorchAvailable] & [flashlight isTorchModeSupported:AVCaptureTorchModeOn]) {
BOOL success = [flashlight lockForConfiguration:Nil];
if(success){
if(switch1.on){ //// or (!(switch1.on))
on.hidden = YES;
[UIScreen mainScreen].brightness = 1.0;
[flashlight setTorchMode:AVCaptureTorchModeOn];
[flashlight unlockForConfiguration];
}
}
}
}
any help would be appreciated
**EDIT:**
Here is the code where i set the switch to no using ibactions when the value of the switch has changed. This code works successfully:
-(IBAction)switch1{
if (switch1.on) {
switch1.on = YES;
switch2.on = NO;
} else{
switch2.on = YES;
switch1.on = NO;
}
}
-(IBAction)switch2{
if (switch2.on) {
switch2.on = YES;
switch1.on = NO;
} else{
switch1.on = YES;
switch2.on = NO;
}
}
Answer
First add a bool:
bool yes;
then set that bool in the viewdidload
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
yes = YES;
}
After that set it to YES when the ibaction is called and set it to NO once the switch is turned off:
-(IBAction)switch1{
if (swich1.on) {
swich1.on = YES;
swich2.on = NO;
yes = YES;
}
}
-(IBAction)switch2{
if (swich2.on) {
swich2.on = YES;
swich1.on = NO;
yes = NO;
}
}
lastly where it checks if(switch1.on){} you need to change it to if(yes==YES){} so together that if statement looks like this:
-(IBAction)torchon:(id)sender{
AVCaptureDevice *flashlight = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
if ([flashlight isTorchAvailable] & [flashlight isTorchModeSupported:AVCaptureTorchModeOn]) {
BOOL success = [flashlight lockForConfiguration:Nil];
if(success){
if(yes==YES){
on.hidden = YES;
[UIScreen mainScreen].brightness = 1.0;
[flashlight setTorchMode:AVCaptureTorchModeOn];
[flashlight unlockForConfiguration];
}
}
}
}

Answer 1

The UISwitch has another getter for the on property.
#property(nonatomic, getter=isOn) BOOL on;
It may be better to use .isOn instead of .on for getting the value.
Also, some of your code can be simplified:
-(IBAction)switch1{
[switch2 setOn:!switch1.isOn];
}
-(IBAction)switch2{
[switch1 setOn:!switch2.isOn];
}
It can get even better if you use the sender of the action in your methods.

Answer 2

It seems that your IBAction methods have a similar form as the getter for the switch. It is possible that this could lead to undesired side effects. Refactor your methods to a single method, more in line with good programming practice:
-(IBAction)switchDidChange:(UISwitch*)aSwitch {
UISwitch* otherSwitch = (aSwitch == switch1)? switch2 : switch1;
[otherSwitch setOn:!aSwitch.on animated:YES];
}
Also, in your code the on property does not really seem to influence what is switched on or off. Include this conditionality.