I want to implement something like cardslib with text inside (Title, description, footer).
I thought to use a IBOutletCollection TextView, but I am open for other solutions.
I've linked from my xib file the collection to my interface.
In my class implementation :
#synthesize myTextViewCollection;
- (void)viewDidLoad {
myTextViewCollection = [NSMutableArray arrayWithObjects:#"one", #"two", #"three", nil];
for (UITextView *myView in myTextViewCollection) {
NSLog(#"%#", myView);
myView.text = #"any text";
}
}
myView contain the three strings : "one", "two", "three".
Output Error :
-[__NSCFConstantString setText:]: unrecognized selector sent to instance 0x461b8
I don't understand why i get this error ...
Thanks !
What are the IBOutlets for your text views? You want something like this:
#property (nonatomic, weak) IBOutlet UITextView* textViewOne;
#property (nonatomic, weak) IBOutlet UITextView* textViewTwo;
#property (nonatomic, weak) IBOutlet UITextView* textViewThree;
Then:
for (UITextView *textView in #[ self.textViewOne, self.textViewTwo, self.textViewThree ]) {
textView.text = #"any text";
}
What you have done is add a bunch of NSString literals to an array, then you're trying to send the setText: selector to an NSString, which is not a selector NSString responds to.
Related
I would like to modify the text property of a UILabel (nameLbl) but don't know what i am wrong.
I have 2 Views, the first is a ViewController, the second is ProfileViewController. The ProfileViewController fill some field of user profile this data are passed to ViewController and showed in UIlabel.
The issue is I can't show the datas in the ViewController.
What am I get wrong?
---ViewController.h---
#interface ViewController : UIViewController
{
IBOutlet ViewController *profile;
IBOutlet UILabel *nameLbl, *celLbl, *cfLbl;
IBOutlet UITextField *nameTF;
}
#property (nonatomic, retain) IBOutlet ViewController *profile;
#property (retain, nonatomic) IBOutlet UILabel *nameLbl, *celLbl, *cfLbl;
#property (nonatomic, retain) IBOutlet UITextField *nameTF;
-(void) setUser: (NSString *) name:(NSString *) cel:(NSString *) cf;
#end
---ViewController.m---
#synthesize nameLbl, celLbl, cfLbl;
-(void) setUser:(NSString *)name:(NSString *)cel:(NSString *)cf
{
nameLbl = [[UILabel alloc] init];
[nameLbl setText:name];
}
this is the connection inspector
https://drive.google.com/file/d/0Bz7WcQmZNuFLMWt3QUo1Tk5XUW8/edit?usp=sharing
Remove
nameLbl = [[UILabel alloc] init];
from your code it seems that the nameLbl UILabel has already been initialized from nib, and you are creating a new memory reference, so its not working.
I created a Food object that I'd like to be able to set and get attributes of (such as time). For some reason I'm allowed to set attributes, but I am not able to the get attributes. I receive the following error by simply calling food.time
Property 'time' not found on object of type 'conts __strong id'
I'm not sure if the problem is with putting it in, and then retrieving it from, an array or if it is how my object class is defined. In this example I've simplified it so that you can see how I'm using it.
Some controller (with other methods not shown here)
#import "Food.h"
- (void)viewDidLoad
{
[super viewDidLoad];
NSArray *foodArray = #[firstFood];
for (id food in foodArray) {
UILabel *foodLabel = [[UILabel alloc]
initWithFrame:CGRectMake(10, 180, self.view.frame.size.width-20, 50)];
foodLabel.backgroundColor = [UIColor clearColor];
foodLabel.text = food.time; // This line causes error
foodLabel.textColor = [UIColor blackColor];
[foodLabel setFont:[UIFont fontWithName:#"Courier" size:14]];
[self.view addSubview:foodLabel];
}
}
Food.h
#import <Foundation/Foundation.h>
#interface Food : NSObject
#property (strong, nonatomic) NSString *time;
#property (strong, nonatomic) NSString *title;
#property (strong, nonatomic) NSString *description;
#property (strong, nonatomic) NSString *place;
#end
Food.m
#import "Food.h"
#implementation Food
#end
As far as the compiler knows food is just a generic NSObject pointer. You either need to cast it to a Food object, or just change your definition within the for loop.
for (Food *food in foodArray) {
//...etc
}
That is assuming firstFood is actually a Food object, since you do not show it's definition in your snippet.
If you don't want to change the type, you can send any message to id, and let it figure out at run-time whether it is valid:
foodLabel.text = [food time];
would also be valid, but you are unable to use the dot syntax on an object of type id, either cast it or use the standard bracket syntax (which will fail at run-time if that object does not respond to that message).
Okay, I know there is a ton of these questions out there, because I've looked and tried some of the solutions. However, many of the ones I tried didn't work or the answer was too over my head for me to really grasp well - I'm a new developer and this is my first app. I learn by learning what not to do at this point.
I have the 'unrecognized selector sent to instance error' on a UIStepper stepperValueChanged setup. Here is the contents of the error message as it is given to me:
[DetailViewController stepperValueChanged]: unrecognized selector sent to instance 0x8637630
I will probably be ripped apart for this, but I can't really understand what's going on here - my only guess so far is to assume it has something to do with the only point in my code where stepperValueChanged exists - under the DetailViewController.h, as placed below:
#interface DetailViewController : UIViewController <UISplitViewControllerDelegate>
{
// Create GUI parameters for text fields, text labels, and the stepper:
IBOutlet UITextField *value1;
IBOutlet UITextField *value2;
IBOutlet UITextField *value3;
IBOutlet UISwitch *double_precision;
IBOutlet UILabel *value1_type;
IBOutlet UILabel *value2_type;
IBOutlet UILabel *value3_type;
IBOutlet UILabel *deriv_units;
IBOutlet UILabel *units;
IBOutlet UILabel *result;
IBOutlet UIStepper *stepper;
}
// Define properties of the above GUI parameters:
#property (nonatomic, retain) UITextField *value1;
#property (nonatomic, retain) UITextField *value2;
#property (nonatomic, retain) UITextField *value3;
#property (nonatomic, retain) UILabel *value1_type;
#property (nonatomic, retain) UILabel *value2_type;
#property (nonatomic, retain) UILabel *value3_type;
#property (nonatomic, retain) UILabel *deriv_units;
#property (nonatomic, retain) UILabel *units;
#property (nonatomic, retain) UILabel *result;
// Setup property as instance of UIStepper:
#property (nonatomic, strong) IBOutlet UIStepper *stepper;
// Setup NSString instance for segue linking:
#property (nonatomic, strong) NSString *equationName;
#property (strong, nonatomic) id detailItem;
#property (weak, nonatomic) IBOutlet UILabel *detailDescriptionLabel;
// IBActions for the Calculate button and UIStepper instance:
- (IBAction)Calculate:(id)sender;
- (IBAction)stepperValueChanged:(id)sender;
- (IBAction)double_precision:(id)sender;
#end
Any ideas what is going on here? I don't have much of a clue, and if anyone can help explain to me what exactly is in play here while addressing it, I would be more than grateful.
If you need the contents of the implementation file, let me know; I'll edit it in.
Relevant areas of the .m file:
#interface DetailViewController ()
#property (strong, nonatomic) UIPopoverController *masterPopoverController;
- (void)configureView;
#end
#implementation DetailViewController
// Synthesize an instance of NSString for segue linking:
#synthesize equationName = _equationName;;
// Synthesize all other variables:
#synthesize value1 = _value1;
#synthesize value2 = _value2;
#synthesize value3 = _value3;
#synthesize value1_type = _value1_type;
#synthesize value2_type = _value2_type;
#synthesize value3_type = _value3_type;
#synthesize deriv_units = _deriv_units;
#synthesize result = _result;
#synthesize units = _units;
#synthesize stepper = _stepper;
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
[self configureView];
self.title = _equationName;
self.stepper.stepValue = 1;
self.stepper.autorepeat = NO;
self.stepper.continuous = YES;
self.stepper.wraps = YES;
int eqNum;
if ((_equationName = #"Energy-Frequency Relation"))
{
eqNum = 1;
self.stepper.minimumValue = 1;
self.stepper.maximumValue = 3;
}
else if ((_equationName = #"Energy-Frequency-Wavelength Relation"))
{
eqNum = 2;
self.stepper.minimumValue = 1;
self.stepper.maximumValue = 4;
}
// Take _equationName quantization and use it in a switch case to determine the formula that IBAction will use:
if (dflt)
{
switch (eqNum)
{
case 1:
if ((stepper.value = 1))
{
// Change deriv_units appropriately:
self.deriv_units.text = #"Energy (Joules)";
// This is a Planck's constant calculation, we hide the second variable as the constant
// is stored:
self.value2.hidden = YES;
self.value2_type.hidden = YES;
self.value3.hidden = YES;
self.value3_type.hidden = YES;
// Now we set up the parameters of the first entry variable:
self.value1_type.text = #"Frequency (in Hz)";
double frequency = [value1.text doubleValue];
double Planck = 6.626069e-34;
double energy = Planck * frequency;
// Now we set up the return field to return results:
NSString* resultIntermediate = [NSString stringWithFormat:#"%f", energy];
self.units.text = #"J";
}
// Identical function statements under ViewDidLoad truncated
}
bool dflt;
-(IBAction)KeyboardGoAway:(id)sender
{
[self.value1 resignFirstResponder];
[self.value1 resignFirstResponder];
[self.value1 resignFirstResponder];
}
-(IBAction)double_precision:(id)sender
{
// Sets double-float 'truth' value depending on state of UISwitch:
if (double_precision.on)
{
dflt = TRUE;
}
else
{
dflt = FALSE;
}
}
#pragma mark - Calculation runtime
-(IBAction)Calculate:(id)sender
{
// Assigns numerical information to _equationName data -
// switch case can only handle integer literals
// Also handles stepper incrementation and UILabel/UITextView hiding
NSString* resultIntermediate;
self.result.text = resultIntermediate;
}
The trailing colon makes the difference. Your action method is stepperValueChanged:,
but from the error message it seems that you connected the stepper to stepperValueChanged.
There are two reason for these kind of issues.
Probable case 1:
You first declared the function like - (IBAction)stepperValueChanged;
Connected the IBAction to stepper
Changed the method to - (IBAction)stepperValueChanged:(id)sender;
Solution:
Delete old connection in the interface builder and connect it again.
Probable case 2:
In your code you are calling the method using a selector where you written like: #selector(stepperValueChanged)
Solution:
Change the selector like: #selector(stepperValueChanged:)
Usually this means you are missing the method in your .m or you might of misspelled stepperValueChanged.
Edit: Actually, I believe it needs to be stepperValueChanged: with a semicolon.
As said in the title, my IBOutletCollection of UIButtons is empty after viewDidLoad.
I created a IBOutletCollection of UILabels the same way, and this one is working perfectly.
Any idea how this can be fixed, or where i made a mistake?
Here is the Code:
#property (strong, nonatomic) IBOutletCollection(UILabel) NSArray *lbl_save;
#property (strong, nonatomic) IBOutletCollection(UILabel) NSArray *lbl_cancel;
#property (strong, nonatomic) IBOutletCollection(UILabel) NSArray *lbl_edit;
#property (strong, nonatomic) IBOutletCollection(UIButton) NSArray *btn_changeData;
#property (strong, nonatomic) IBOutletCollection(UIButton) NSArray *btn_save;
#property (strong, nonatomic) IBOutletCollection(UIButton) NSArray *btn_cancel;
The buttons are placed in a xib and linked correctly to the corresponding outlets. Just like the labels.
The time i press the one of the Buttons is the first time, i want to access the Buttons in Code.
for (UIButton *btn in _btn_changeData) {
btn.hidden = NO;
btn.userInteractionEnabled = YES;
}
for (UIButton *btn in _btn_save) {
btn.hidden = YES;
btn.userInteractionEnabled = NO;
}
for (UIButton *btn in _btn_cancel) {
btn.hidden = YES;
btn.userInteractionEnabled = NO;
}
for (UILabel *lbl in _lbl_save) {
lbl.hidden = YES;
}
for (UILabel *lbl in _lbl_cancel) {
lbl.hidden = YES;
}
for (UILabel *lbl in _lbl_edit) {
lbl.hidden = NO;
}
That is also where i got the following Exception and realized, that my Button OUtletcollection is empty.
-[UIButton countByEnumeratingWithState:objects:count:]: unrecognized selector sent to instance 0xa8a8850
I neither overwrite the outletcollection, nor do i change attributes of the buttons.
Its just that the labels are there in the collection and the buttons not. And i have no idea why.
Thx in advance for any help.
Mav
First idea that comes to my mind is that the properties are not correctly synthesized. Is _btn_changeData really the ivar behind btn_changeData property?
Second idea is something I saw while debugging someone else's code. When outlets are incorrectly connected, for example, if the controller references itself, two controller instances can be create. Obviously only of of them will have the outlets connected. Make sure only of instance is created.
For debugging, implementing the setter by yourself might be a good idea.
Edit:
After rereading, the problem is actually different they you say in your question. The error message -[UIButton countByEnumeratingWithState:objects:count:]: unrecognized selector sent to instance 0xa8a8850
doesn't mean that _btn_changeData is an empty array. It means there is a UIButton instead of an array.
Having said this, you should check if you are not overwriting the data in _btn_changeData somewhere.
I have a lot of buttons that i would like to give a title when the view is loaded.
The title of the buttons varies depending on what day of the month it is. Therefore I have created an array with the name of all the buttons. My code is as follows:
My interface:
#property (strong, nonatomic) IBOutlet UIButton *button1;
#property (strong, nonatomic) IBOutlet UIButton *button2;
#property (strong, nonatomic) IBOutlet UIButton *button3;
#property (strong, nonatomic) IBOutlet UIButton *button4;
#property (strong, nonatomic) IBOutlet UIButton *button5;
#property (strong, nonatomic) IBOutlet UIButton *button6;
#property (strong, nonatomic) IBOutlet UIButton *button7;
#property (strong, nonatomic) IBOutlet UIButton *button8;
#property (strong, nonatomic) IBOutlet UIButton *button9;
#property (strong, nonatomic) IBOutlet UIButton *button10;
My implementation:
#synthesize button1 = _button1;
#synthesize button2 = _button2;
#synthesize button3 = _button3;
#synthesize button4 = _button4;
#synthesize button5 = _button5;
#synthesize button6 = _button6;
#synthesize button7 = _button7;
#synthesize button8 = _button8;
#synthesize button9 = _button9;
#synthesize button10 = _button10;
NSArray *myArray = [NSArray arrayWithObjects: #"dummyButton", #"_button1", #"_button2", #"_button3", #"_button4", #"_button5", #"_button6", #"_button7", #"_button8", #"_button9", #"_button10", nil];
for (int i = varDefinedEarlier; i<=totalAmountOfNeededTitles; i++) {
NSString *theTitleSting = [NSString stringWithFormat:#"%i",i];
NSLog(#"arrayValue:%#", [myArray objectAtIndex:i]); //Works prints the button name (for example _button7)
[[myArray objectAtIndex:i] setTitle:theTitleSting forState:UIControlStateNormal];
//The line above is where the app crashes. Everything else works just fine.
}
The error provided to me is a "Thread 1: signal SIGABRT
Besides that, this is what the log says:
-[__NSCFConstantString setTitle:forState:]: unrecognized selector sent to instance 0x14a48
2012-07-10 22:57:49.649 Don't Break the Chain[10302:707] * * * Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFConstantString setTitle:forState:]: unrecognized selector sent to instance 0x14a48'
* * * First throw call stack:
(0x3774788f 0x3544c259 0x3774aa9b 0x37749915 0x376a4650 0xdc2f 0x31454c8b 0x314611e9 0x31461059 0x31460f3f 0x3146070b 0x31460503 0x31454aff 0x314547d5 0x314cd903 0x31547627 0x37fb8933 0x3771ba33 0x3771b699 0x3771a26f 0x3769d4a5 0x3769d36d 0x33e5c439 0x31449cd5 0xb7cf 0xb774)
terminate called throwing an exception(lldb)
I think the error is the way i try to tell the app witch button it needs to set a title to, but I can not really figure out how to get it to take on the value of my array and use it as the button name.
I'm pretty new in iPhone iOS development, so bear with me if the answer is simple ;)
You are not referencing the button instances but some strings within that array. Now within your loop, you are trying to invoke the method setTitle:forState: on those strings which does not exist for NSString instances.
Try the following:
NSArray *myArray = [NSArray arrayWithObjects:_button1, _button2, _button3, _button4, _button5, _button6, _button7, _button8, _button9, _button10, nil];
This will place the actual button instances into your array, as intended and your code should work fine.
you should do something like [myButton setTitle:[myArray objectAtIndex:i] forState: UIControlStateNormal]
at the moment you are passing the setTitle message to a string type which - of course - should result in a crash...
hope it helps