/* |
Copyright (C) 2014 Apple Inc. All Rights Reserved. |
See LICENSE.txt for this sample’s licensing information |
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*/ |
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#import "ReverseViewController.h" |
#import "PlacemarksListViewController.h" |
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#define kSanFranciscoCoordinate CLLocationCoordinate2DMake(37.776278, -122.419367) |
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@interface ReverseViewController () <UITableViewDelegate, UITableViewDataSource, CLLocationManagerDelegate> |
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@property (nonatomic, strong) CLLocationManager *locationManager; |
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@property (readonly) CLLocationCoordinate2D currentUserCoordinate; |
@property (readonly) NSInteger selectedRow; |
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@property (weak, readonly) UIActivityIndicatorView *spinner; |
@property (weak, readonly) UIActivityIndicatorView *currentLocationActivityIndicatorView; |
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@end |
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#pragma mark - |
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@implementation ReverseViewController |
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- (void)viewDidLoad |
{ |
[super viewDidLoad]; |
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// start with San Francisco |
_currentUserCoordinate = kCLLocationCoordinate2DInvalid; |
_selectedRow = 0; |
} |
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#pragma mark - UI Handling |
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- (void)showSpinner:(UIActivityIndicatorView *)whichSpinner withShowState:(BOOL)show |
{ |
whichSpinner.hidden = (show) ? NO : YES; |
if (show) |
{ |
[whichSpinner startAnimating]; |
} |
else |
{ |
[whichSpinner stopAnimating]; |
} |
} |
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- (void)showCurrentLocationSpinner:(BOOL)show |
{ |
UITableViewCell *cell = [self.tableView cellForRowAtIndexPath:[NSIndexPath indexPathForRow:1 inSection:0]]; |
assert(cell); |
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if (!_currentLocationActivityIndicatorView) |
{ |
// add the spinner to the table cell |
UIActivityIndicatorView *curLocSpinner = |
[[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray]; |
[curLocSpinner startAnimating]; |
[curLocSpinner setFrame:CGRectMake(200.0, 0.0, 22.0, 22.0)]; |
[curLocSpinner setAutoresizingMask:UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin]; |
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_currentLocationActivityIndicatorView = curLocSpinner; // keep a weak ref around for later |
cell.accessoryView = _currentLocationActivityIndicatorView; |
} |
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if (!show && _selectedRow == 1) |
{ |
cell.accessoryView = nil; |
cell.accessoryType = UITableViewCellAccessoryCheckmark; |
} |
} |
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- (void)showSpinner:(BOOL)show |
{ |
if (self.spinner == nil) |
{ |
// add the spinner to the table's footer view |
UIView *containerView = [[UIView alloc] initWithFrame: |
CGRectMake(0.0, 0.0, CGRectGetWidth(self.tableView.frame), 22.0)]; |
UIActivityIndicatorView *spinner = |
[[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray]; |
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// size and center the spinner |
[spinner setFrame:CGRectZero]; |
[spinner sizeToFit]; |
CGRect frame = spinner.frame; |
frame.origin.x = (CGRectGetWidth(self.tableView.frame) - CGRectGetWidth(frame)) / 2.0; |
spinner.frame = frame; |
[spinner startAnimating]; |
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[containerView addSubview:spinner]; |
self.tableView.tableFooterView = containerView; |
_spinner = spinner; // keep a weak ref around for later |
} |
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[self showSpinner:self.spinner withShowState:show]; |
} |
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- (void)lockUI:(BOOL)lock |
{ |
// prevent user interaction while we are processing the forward geocoding |
self.tableView.allowsSelection = !lock; |
[self showSpinner:lock]; |
} |
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#pragma mark - Display Results |
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// display the results |
- (void)displayPlacemarks:(NSArray *)placemarks |
{ |
dispatch_async(dispatch_get_main_queue(),^ { |
[self lockUI:NO]; |
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PlacemarksListViewController *plvc = [[PlacemarksListViewController alloc] initWithPlacemarks:placemarks preferCoord:YES]; |
[self.navigationController pushViewController:plvc animated:YES]; |
}); |
} |
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// display a given NSError in an UIAlertView |
- (void)displayError:(NSError*)error |
{ |
dispatch_async(dispatch_get_main_queue(),^ { |
[self lockUI:NO]; |
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NSString *message; |
switch ([error code]) |
{ |
case kCLErrorGeocodeFoundNoResult: message = @"kCLErrorGeocodeFoundNoResult"; |
break; |
case kCLErrorGeocodeCanceled: message = @"kCLErrorGeocodeCanceled"; |
break; |
case kCLErrorGeocodeFoundPartialResult: message = @"kCLErrorGeocodeFoundNoResult"; |
break; |
default: message = [error description]; |
break; |
} |
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UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"An error occurred." |
message:message |
delegate:nil |
cancelButtonTitle:@"OK" |
otherButtonTitles:nil];; |
[alert show]; |
}); |
} |
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#pragma mark - UITableViewDataSource |
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- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView |
{ |
// return the number of sections |
return 2; |
} |
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- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section |
{ |
// return the number of rows in the section |
if (section == 0) |
return 2; |
else |
return 1; |
} |
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- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section |
{ |
if (section == 0) |
return @"Choose a location:"; |
else |
return nil; |
} |
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- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath |
{ |
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"basicCell"]; |
if (!cell) |
{ |
UITableViewCellStyle style = (indexPath.section == 0) ? UITableViewCellStyleSubtitle : UITableViewCellStyleDefault; |
cell = [[UITableViewCell alloc] initWithStyle:style reuseIdentifier:@"basicCell"]; |
} |
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if (indexPath.section == 0) |
{ |
switch (indexPath.row) |
{ |
case 0: |
{ |
cell.textLabel.text = @"San Francisco"; |
cell.detailTextLabel.text = [NSString stringWithFormat:@"φ:%.4F, λ:%.4F", kSanFranciscoCoordinate.latitude, kSanFranciscoCoordinate.longitude]; |
break; |
} |
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case 1: |
{ |
cell.textLabel.text = @"Current Location"; |
if (CLLocationCoordinate2DIsValid(_currentUserCoordinate)) |
cell.detailTextLabel.text = [NSString stringWithFormat:@"φ:%.4F, λ:%.4F", _currentUserCoordinate.latitude, _currentUserCoordinate.longitude]; |
else |
{ |
if ([CLLocationManager authorizationStatus] == kCLAuthorizationStatusDenied || |
[CLLocationManager authorizationStatus] == kCLAuthorizationStatusRestricted ) |
{ |
cell.detailTextLabel.text = @"Location Services Disabled"; |
} |
else |
{ |
cell.detailTextLabel.text = @"<unknown>"; |
} |
} |
break; |
} |
} |
cell.selectionStyle = UITableViewCellSelectionStyleNone; |
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UITableViewCellAccessoryType accessoryType = |
(_selectedRow == indexPath.row) ? UITableViewCellAccessoryCheckmark : UITableViewCellAccessoryNone; |
cell.accessoryType = accessoryType; |
} |
else |
{ |
cell.textLabel.text = @"Geocode Coordinate"; |
cell.textLabel.textAlignment = NSTextAlignmentCenter; |
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator; |
} |
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return cell; |
} |
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#pragma mark - UITableViewDelegate |
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- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath |
{ |
[[tableView cellForRowAtIndexPath:indexPath] setSelected:NO]; |
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if (indexPath.section == 1 && indexPath.row == 0) |
{ |
// perform the Geocode |
[self performCoordinateGeocode:self]; |
} |
else |
{ |
NSInteger whichCellRow = (indexPath.row == 0) ? 1 : 0; |
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UITableViewCell *cell = [self.tableView cellForRowAtIndexPath:[NSIndexPath indexPathForRow:whichCellRow inSection:0]]; |
cell.accessoryType = UITableViewCellAccessoryNone; |
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cell = [self.tableView cellForRowAtIndexPath:indexPath]; |
cell.accessoryType = UITableViewCellAccessoryCheckmark; |
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if (indexPath.row == 1) |
{ |
[self startUpdatingCurrentLocation]; |
} |
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_selectedRow = indexPath.row; |
} |
} |
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#pragma mark - CLLocationManagerDelegate |
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- (void)startUpdatingCurrentLocation |
{ |
// if location services are restricted do nothing |
if ([CLLocationManager authorizationStatus] == kCLAuthorizationStatusDenied || |
[CLLocationManager authorizationStatus] == kCLAuthorizationStatusRestricted ) |
{ |
return; |
} |
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// if locationManager does not currently exist, create it |
if (self.locationManager == nil) |
{ |
_locationManager = [[CLLocationManager alloc] init]; |
[self.locationManager setDelegate:self]; |
self.locationManager.distanceFilter = 10.0f; // we don't need to be any more accurate than 10m |
} |
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// for iOS 8, specific user level permission is required, |
// "when-in-use" authorization grants access to the user's location |
// |
// important: be sure to include NSLocationWhenInUseUsageDescription along with its |
// explanation string in your Info.plist or startUpdatingLocation will not work. |
// |
if ([_locationManager respondsToSelector:@selector(requestWhenInUseAuthorization)]) |
{ |
[_locationManager requestWhenInUseAuthorization]; |
} |
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[_locationManager startUpdatingLocation]; |
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[self showCurrentLocationSpinner:YES]; |
} |
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- (void)stopUpdatingCurrentLocation |
{ |
[_locationManager stopUpdatingLocation]; |
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[self showCurrentLocationSpinner:NO]; |
} |
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- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation |
{ |
// if the location is older than 30s ignore |
if (fabs([newLocation.timestamp timeIntervalSinceDate:[NSDate date]]) > 30) |
{ |
return; |
} |
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_currentUserCoordinate = [newLocation coordinate]; |
_selectedRow = 1; |
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// update the current location cells detail label with these coords |
UITableViewCell *cell = [self.tableView cellForRowAtIndexPath:[NSIndexPath indexPathForRow:1 inSection:0]]; |
cell.detailTextLabel.text = [NSString stringWithFormat:@"φ:%.4F, λ:%.4F", _currentUserCoordinate.latitude, _currentUserCoordinate.longitude]; |
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// after recieving a location, stop updating |
[self stopUpdatingCurrentLocation]; |
} |
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- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error |
{ |
NSLog(@"%@", error); |
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// stop updating |
[self stopUpdatingCurrentLocation]; |
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// since we got an error, set selected location to invalid location |
_currentUserCoordinate = kCLLocationCoordinate2DInvalid; |
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// show the error alert |
UIAlertView *alert = [[UIAlertView alloc] init]; |
alert.title = @"Error updating location"; |
alert.message = [error localizedDescription]; |
[alert addButtonWithTitle:@"OK"]; |
[alert show]; |
} |
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#pragma mark - Actions |
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- (IBAction)performCoordinateGeocode:(id)sender |
{ |
[self lockUI:YES]; |
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CLGeocoder *geocoder = [[CLGeocoder alloc] init]; |
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CLLocationCoordinate2D coord = (_selectedRow == 0) ? kSanFranciscoCoordinate : _currentUserCoordinate; |
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CLLocation *location = [[CLLocation alloc] initWithLatitude:coord.latitude longitude:coord.longitude]; |
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[geocoder reverseGeocodeLocation:location completionHandler:^(NSArray *placemarks, NSError *error) { |
if (error){ |
NSLog(@"Geocode failed with error: %@", error); |
[self displayError:error]; |
return; |
} |
NSLog(@"Received placemarks: %@", placemarks); |
[self displayPlacemarks:placemarks]; |
}]; |
} |
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@end |
