IOS app not recognizing accelerometer data or text input - ios

Question

This code is not giving me any output or even setting up the accelerometer it seems. I am first and foremost trying to get the device to recognize the accelerometer and the thresh input. It is a simple accelerometer app where I can set up a thresh hold variable where I can then compare some values from previous and current accelerometer output. The thresh input is a simple text box for input. Any help would be appreciated.
#import "ViewController.h"
#interface ViewController (){
//set up variables for switch and BOOL variables
BOOL isStarted;
BOOL switchX;
BOOL switchY;
BOOL switchZ;
}
#end
#implementation ViewController
-(IBAction)startSensor:(id)sender{
//start with displaying the values...then move onto the just flash method
//set up the accelerometer function within the button press
[self.motionManager startAccelerometerUpdatesToQueue:[NSOperationQueue currentQueue] withHandler:^(CMAccelerometerData *accelerometerData, NSError *error) {
[self showAccelerationdata:accelerometerData.acceleration];
//print statements for future debugging. only in the log files though
if (error){
NSLog(#"%#", error);
}
}];
}
-(void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
currentAccelx = 0;
currentAccely = 0;
currentAccelz = 0;
previousAccelx = 0;
previousAccely = 0;
previousAccelz = 0;
//set up class for movement controls
self.motionManager = [[CMMotionManager alloc] init];
self.motionManager.accelerometerUpdateInterval = .1;
}
-(IBAction)checkSwitchx:(UISwitch *)sender{
if (sender.on){
switchX = TRUE;
}
else{
switchX = FALSE;
}
}
-(IBAction)checkSwitchy:(UISwitch *)sender{
if (sender.on){
switchY = TRUE;
}
else{
switchY = FALSE;
}
}
-(IBAction)checkSwitchz:(UISwitch *)sender{
if (sender.on){
switchZ = TRUE;
}
else{
switchZ = FALSE;
}
}
-(void)showAccelerationdata:(CMAcceleration)acceleration
{
self.view.backgroundColor = [UIColor whiteColor];
if ([thresh.text length] == 0){
UIAlertView *alert = [[UIAlertView alloc]
initWithTitle:#"numbers are blank!" message:#"Please enter numbers!"
delegate:self cancelButtonTitle:#"Ok!" otherButtonTitles: nil];
[alert show];
[alert resignFirstResponder];
}
else{
threshold = [thresh.text floatValue];
NSLog(#"%#", thresh);
}
}
-(void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#end

Answer 1

Show the code where you set self.motionManager.
If you don't actually create a CMMotionManager, you are sending messages to nil in the startSensor: method, and you will observe that no accelerometer callbacks are executed.

Answer 2

I did not set up my CMMotionManager correctly it seems. After I looked at my setup it was pretty straight-forward on how to get everything to display correctly.