So I have a ZBarView within a UIViewController (for an embedded scanner) and I was wondering how I could change the Green Border to have it something like this?
#import "ZBarSDK.h"
#interface ScanViewController : UIViewController <ZBarReaderViewDelegate>
#property (nonatomic, strong) IBOutlet ZBarReaderView *readerView;
#property (strong, nonatomic) IBOutlet UILabel *scannedMachineLabel;
#end
- (void)viewDidLoad
{
[super viewDidLoad];
_readerView.readerDelegate = self;
// ensure initial camera orientation is correctly set
UIApplication *app = [UIApplication sharedApplication];
[_readerView willRotateToInterfaceOrientation: app.statusBarOrientation
duration: 0];
}
Related
I am working on this couple of days and I can't figure out what I am doing wrong.
First, I don't know if the KVO is the best way to pass the value of the clicked row info from one view controller to another view controller.
I have Main view, with 2 buttons only. Clicking on one of the buttons, I open MasterTableViewController, where I have the NSTableView with some records (one column only) from core data.
On click on the NSTableView, I am opening the DetailViewController, where I have only one label.
What I am trying is to change the label value, with the value of the clicked row in the NSTableView.
While I can print the value of the clicked row in the DetailViewController, I can't change the label value. I assume that notification comes before the viewDidLoad get called.
I have the following code:
In my MasterTableViewController.h file:
#import <Cocoa/Cocoa.h>
#import "AppDelegate.h"
#interface MasterTableViewController : NSViewController
#property (nonatomic,strong) NSManagedObjectContext *mObjContext;
#property (weak) IBOutlet NSTableView *websitesTableView;
- (IBAction)tableViewDoubleClick:(id)sender;
#property (nonatomic,strong) NSString *cellValue;
#end
In my MasterTableViewController.m file:
#import "MasterTableViewController.h"
#import "DetailViewController.h"
#interface MasterTableViewController ()
#end
#implementation MasterTableViewController
-(void)awakeFromNib {
[_websitesTableView setTarget:self];
[_websitesTableView setDoubleAction:#selector(tableViewDoubleClick:)];
}
- (void)viewDidLoad {
[super viewDidLoad];
// Get the object managed context
AppDelegate *appDelegate = (AppDelegate*)[[NSApplication sharedApplication] delegate];
self.mObjContext = appDelegate.managedObjectContext;
}
- (IBAction)tableViewDoubleClick:(id)sender {
NSInteger rowNumber = [_websitesTableView clickedRow];
NSTableColumn *column = [_websitesTableView tableColumnWithIdentifier:#"websiteUrl"];
NSCell *cell = [column dataCellForRow:rowNumber];
_cellValue = [cell stringValue];
MasterTableViewController *mtvc = [[MasterTableViewController alloc]initWithNibName:#"MasterTableViewController" bundle:nil];
DetailViewController *dvc = [[DetailViewController alloc]initWithNibName:#"DetailViewController" bundle:nil];
[mtvc addObserver:dvc
forKeyPath:#"cellValue"
options:NSKeyValueObservingOptionNew
context:NULL];
[mtvc setCellValue:_cellValue];
[mtvc removeObserver:dvc forKeyPath:#"cellValue"];
AppDelegate *appDelegate = (AppDelegate*)[[NSApplication sharedApplication] delegate];
[appDelegate changeViewController:2];
}
#end
Code for the DetailViewController.h is:
#import <Cocoa/Cocoa.h>
#import "AppDelegate.h"
#interface DetailViewController : NSViewController
#property (nonatomic, weak) AppDelegate *appDelegate;
#property (weak) IBOutlet NSTextField *detailLabel;
#property (nonatomic,strong) NSString *transferedLabelValue;
#property (nonatomic,strong) NSString *cellValue;
#end
Code for the DetailViewController.m is:
#import "DetailViewController.h"
#import "MasterTableViewController.h"
#interface DetailViewController ()
#end
#implementation DetailViewController
- (void)viewDidLoad {
[super viewDidLoad];
// if I uncomment this line, program crashes, because the value of the _transferedLabelValue is null here.
//[_detailLabel setStringValue:_transferedLabelValue];
}
-(void)observeValueForKeyPath:(NSString *)keyPath
ofObject:(id)object
change:(NSDictionary *)change
context:(void *)context {
if ([keyPath isEqualToString:#"cellValue"]) {
_transferedLabelValue = [change objectForKey:NSKeyValueChangeNewKey];
// Here I get the value of the clicked cell, it is printed in the console. However if I try to change the label value here, doesn't work, since seems that label does not exist yet at this point....
NSLog(#"Value in the observerValueForKeyPath is:%#",_transferedLabelValue);
}
}
#end
Code from the AppDelegate.h :
#import <Cocoa/Cocoa.h>
#interface AppDelegate : NSObject <NSApplicationDelegate>
#property (readonly, strong, nonatomic) NSPersistentStoreCoordinator *persistentStoreCoordinator;
#property (readonly, strong, nonatomic) NSManagedObjectModel *managedObjectModel;
#property (readonly, strong, nonatomic) NSManagedObjectContext *managedObjectContext;
#property (weak) IBOutlet NSView *mainAppView;
#property (nonatomic,strong) NSViewController *mainAppViewController;
- (IBAction)showMasterViewButtonHasBeenClicked:(id)sender;
- (IBAction)showDetailViewButtonHasBeenClicked:(id)sender;
- (void)changeViewController:(NSInteger)tag;
#end
Here is only the relevant code from the AppDelegatge.m, the boiler plate code is omited.
#import "AppDelegate.h"
#import "MasterTableViewController.h"
#import "DetailViewController.h"
#interface AppDelegate ()
#property (weak) IBOutlet NSWindow *window;
- (IBAction)saveAction:(id)sender;
#end
#implementation AppDelegate
- (IBAction)showMasterViewButtonHasBeenClicked:(id)sender {
NSInteger tag = [sender tag];
[self changeViewController:tag];
}
- (IBAction)showDetailViewButtonHasBeenClicked:(id)sender {
NSInteger tag = [sender tag];
[self changeViewController:tag];
}
- (void)changeViewController:(NSInteger)tag {
[[_mainAppViewController view]removeFromSuperview];
switch (tag) {
case 1:
self.mainAppViewController = [[MasterTableViewController alloc]initWithNibName:#"MasterTableViewController" bundle:nil];
[_mainAppView addSubview:[_mainAppViewController view]];
[[_mainAppViewController view] setFrame:[_mainAppView bounds]];
[[_mainAppViewController view] setAutoresizingMask:NSViewWidthSizable | NSViewHeightSizable];
break;
case 2:
self.mainAppViewController = [[DetailViewController alloc]initWithNibName:#"DetailViewController" bundle:nil];
[_mainAppView addSubview:[_mainAppViewController view]];
[[_mainAppViewController view] setFrame:[_mainAppView bounds]];
[[_mainAppViewController view] setAutoresizingMask:NSViewWidthSizable | NSViewHeightSizable];
break;
}
}
Again, if the KVO and notification is not the best way to go, please let me know how I should "inform" the other view which row has been clicked and which is his value.
Regards, John
I manage to solve my problem with the KVO...My problem was that I was creating new instances of the view controllers in the MasterTableViewController...What I did was I created properties for the ViewControllers in the appDelegatge.h like this:
#property MasterTableViewController *mtvc;
#property DetailViewController *dvc;
and then in the appDelegate.m :
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification {
_mtvc = [[MasterTableViewController alloc]initWithNibName:#"MasterTableViewController" bundle:nil];
_dvc = [[DetailViewController alloc]initWithNibName:#"DetailViewController" bundle:nil];
}
Rest of the changes in the code are just replacing the MasterTableViewController and DetailViewController with _mtvc and _dvc...
However...I had been warned that this solution is error prone, and that warning shows true. It happens from time to time that I get wrong value, not the clicked one. Once in 4-5 clicks, I get wrong value. What makes me confuse is that I make the function to work on double click, but it works on single click as well...But those things are for some other question I guess.
I'm trying to create an app that has three UISlider used for selecting R, G and B values. The slider should change the colour of a label according to the sliders values.
ViewController.h
#import <UIKit/UIKit.h>
#interface ViewController : UIViewController
{
NSInteger color;
IBOutlet UISlider *redSlider;
IBOutlet UISlider *greenSlider;
IBOutlet UISlider *blueSlider;
IBOutlet UILabel *colorLabel;
}
#property (nonatomic, retain) UISlider *redSlider;
#property (nonatomic, retain) UISlider *greenSlider;
#property (nonatomic, retain) UISlider *blueSlider;
colorLabel.textColor = [UIColor colorWithRed: redSlider.value green:greenSlider.value
blue:blueSlider.value alpha:1];
#end
ViewController.m
#import "ViewController.h"
#interface ViewController ()
#end
#implementation ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#synthesize redSlider, greenSlider, blueSlider;
#end
This is what I have so far and I'm totally stuck.
You can do this like...
ViewController.h
#import <UIKit/UIKit.h>
#interface ViewController : UIViewController
#end
ViewController.m
#import "ViewController.h"
#interface ViewController ()
// you need to make sure these are actually created
// and give them all a target of self and action sliderValueChanged
#property (nonatomic, retain) UISlider *redSlider;
#property (nonatomic, retain) UISlider *greenSlider;
#property (nonatomic, retain) UISlider *blueSlider;
// not sure where this is set up
#property (nonatomic, strong) UILabel *colorLabel;
#end
#implementation ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
// You may have to create your labels and sliders in here...
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (void)sliderValueChanged
{
// the sliders have changed so set the colour of the label
// based on the new values of the sliders.
self.colorLabel.textColor = [UIColor colorWithRed:self.redSlider.value
green:self.greenSlider.value
blue:self.blueSlider.value
alpha:1.0];
}
#end
Because you don't actually have a question I'm going to take a guess that your code doesn't compile, because it wouldn't.
colorLabel.textColor = [UIColor colorWithRed: redSlider.value green:greenSlider.value blue:blueSlider.value alpha:1];
The above line doesn't belong in you interface. I would recommend you change the code you currently have to something like.
ViewController.h
#interface ViewController : UIViewController
// You don't need the ivars anymore these get generated with the properties below
#property (nonatomic, retain) IBOutlet UISlider *redSlider;
#property (nonatomic, retain) IBOutlet UISlider *greenSlider;
#property (nonatomic, retain) IBOutlet UISlider *blueSlider;
#property (nonatomic, retain) IBOutlet UILabel *colorLabel
#property (assign) NSInteger color;
#end
ViewController.m
#implementation ViewController
// Also no need for the synthesize as these also get generated automatically
- (void)viewDidLoad
{
[super viewDidLoad];
// To change the actual color when changing the value of a slider move this to a method that gets called on slider changed.
colorLabel.textColor = [UIColor colorWithRed:self.redSlider.value green:self.greenSlider.value self.blue:blueSlider.value alpha:1];
}
#end
And once you actually ask a question I might also be able to help you with that.
Your ViewController.h :-
#import <UIKit/UIKit.h>
#interface ViewController : UIViewController
{
IBOutlet UISlider *redSlider;
IBOutlet UISlider *greenSlider;
IBOutlet UISlider *blueSlider;
IBOutlet UILabel *colorLabel;
}
#property (nonatomic, retain) UISlider *redSlider;
#property (nonatomic, retain) UISlider *greenSlider;
#property (nonatomic, retain) UISlider *blueSlider;
#end
and your ViewController.m will be like this:-
#import "ViewController.h"
#interface ViewController ()
#end
#implementation ViewController
#synthesize redSlider, greenSlider, blueSlider;
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
[self changeLabelColor];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
-(Void) changeLabelColor
{
colorLabel.backgroundcolor = [UIColor colorWithRed:redSlider.value green:redSlider.value blue:redSlider.value alpha:1.0];
}
#end
As i didn’t copied paste and i have written it, there might be some typo..
textcolor wouldn’t change label color so i changed it to backgroundcolor.
you can also add slider method with IBAction.
I'm building a camera application, and I can't get the zooming on the image to work. I honestly don't know where to go from here, I'm sure it's some dumb mistake that I'm missing though. The app sets the chosenImageView to the workingImage (picture from the camera). When I try to zoom, nothing happens.
ViewController.h
#interface ViewController : UIViewController <UIActionSheetDelegate, UIImagePickerControllerDelegate, UIScrollViewDelegate>
#property (strong, nonatomic) UIImage *workingImage;
#property (weak, nonatomic) IBOutlet UIImageView *chosenImageView;
#property (weak, nonatomic) IBOutlet UIScrollView *imageScroller;
-(IBAction)cameraButtonPressed;
#end
ViewController.m
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
self.imageScroller.minimumZoomScale = 0.01f;
self.imageScroller.maximumZoomScale = 6.0f;
self.imageScroller.contentSize = self.imageScroller.frame.size;
self.imageScroller.scrollEnabled = YES;
self.navigationController.navigationBar.tintColor = [UIColor blackColor];
}
-(UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView
{
return self.chosenImageView;
}
Here was the problem. You have to control+drag from the UIScrollView to the View Controller to set the delegate.
In controller I have label property:
#interface BallsViewController : UIViewController <UIInteraction>
#property (weak, nonatomic) IBOutlet UILabel *ScoreLabel;
-(void)UpdateScore:(int)score;
#end
#interface BallsViewController ()
#end
#implementation BallsViewController
#synthesize ScoreLabel;
- (void)viewDidLoad
{
[super viewDidLoad];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
-(void)UpdateScore:(int)score
{
NSString *scoreStr =[NSString stringWithFormat:#"%d",score];
[self.ScoreLabel setText:scoreStr];
[self.InfoLabel setText:scoreStr];
}
#end
UpdateScore is protocol method. When I want to set text to ScoreLabel it have value : ScoreLabel UILabel * 0x00000000
It means that it is not initialize?
When I set text, on ui it not change.
Try setting your Label as Strong.
#property (strong, nonatomic) IBOutlet UILabel *ScoreLabel;
I'm trying to write my first iPad app using Xcode 4: it's based on "Tabbed Application" template with two views. On the first view, user selects a City (label displays selection) and on the second wiew there is a IBOutletCollection(UITextField) NSArray *playersData. I want to set the city selected on first view as a default city on second view. I have checked storyboard connections and they seem to be ok.
I get nothing. Any idea?
First view :
#import
#interface pruebaF1FirstViewController : UIViewController
- (IBAction)selectCity:(UIButton *)sender;
#property (weak, nonatomic) IBOutlet UILabel *citySelected;
#end
First view implementation :
#import "pruebaF1FirstViewController.h"
#import "pruebaF1SecondViewController.h"
#interface pruebaF1FirstViewController ()
#property pruebaF1SecondViewController *secondView;
#end
#implementation pruebaF1FirstViewController
#synthesize citySelected;
#synthesize secondView;
- (void)viewDidLoad
...
- (IBAction)selectCity:(UIButton *)sender {
NSString *currentCity =[sender currentTitle];
citySelected.text=#"";
citySelected.text =[citySelected.text stringByAppendingString:currentCity];
/*writes null*/
secondView.defaultCity.text=[NSString stringWithFormat:#"%#" ,currentCity];
NSLog(#"%#",secondView.defaultCity.text);
}
#end
Second view header
#import <UIKit/UIKit.h>
#interface pruebaF1SecondViewController : UIViewController <UITextFieldDelegate>
#property (strong, nonatomic) IBOutletCollection(UITextField) NSArray *playersData;
#property (retain, nonatomic) IBOutlet UITextField *defaultCity;
- (IBAction)eraseData:(UIButton *)sender;
- (IBAction)savePlayersData:(UIButton *)sender;
- (IBAction)termsPopUp:(UIButton *)sender;
/*- (void)writeDefaultCity:(NSString *)currentCity;*/
#end
Second view implementation
#import "pruebaF1SecondViewController.h"
#import "pruebaF1FirstViewController.h"
#interface pruebaF1SecondViewController ()
#property (nonatomic, strong)pruebaF1FirstViewController *prueba;
#end
#implementation pruebaF1SecondViewController
#synthesize playersData;
#synthesize defaultCity;
#synthesize prueba;
- (void)viewDidLoad
{
[super viewDidLoad];
}
- (void)viewDidUnload
{
[self setPlayersData:nil];
[self setDefaultCity:nil];
[super viewDidUnload];
}
/* Return or Done button dismiss keyboard*/
-(BOOL)textFieldShouldReturn:(UITextField *)boxes
{
for (UITextField *boxes in playersData) {
[boxes resignFirstResponder];
}
return YES;
}
....
/*Trying to get city's name from first view in two ways*/
/*-(void)setDefaultCity
{
NSString *defecto=prueba.citySelected.text;
self.defaultCity.text = defecto;
}*/
- (IBAction)eraseData:(UIButton *)sender {
for (UITextField *boxes in playersData) {
boxes.text = #" ";
}
}
/*
-(void)writeDefaultCity:(NSString *)currentCity
{
defaultCity.text =[NSString stringWithFormat:#"%#" ,currentCity];
NSLog(#"Ciudad elegida: %#",currentCity);
}*/
....
#end
Views are generally not loaded until they are displayed on the device, and may be unloaded at any time when not visible to save memory. This means that when you're setting the 'text' property of the 'defaultCity', that label has not yet been created.
Instead you should add a NSString * property to pruebaF1SecondViewController and set the value of the defaultCity label in viewDidLoad:
In the header:
#property (nonatomic, weak) UILabel *defaultCityLabel;
#property (nonatomic, strong) NSString *defaultCity;
In the implementation
- (void)viewDidLoad
{
[super viewDidLoad];
defaultCityLabel.text = defaultCity;
}
And in the first view controller, assign the string value instead of the label value.