I am facing problem in custom initialization of my subview class the method somewhat look like this
my sub view .h file lloks like this
#import <UIKit/UIKit.h>
#interface mysubview : UIView
#property(nonatomic,strong)UIButton *mybutton;
#end
ViewController.m file
-(id)initWithbutton:(CGRect)frame color:(UIColor*)mycolor
{
NSLog(#"Into the initializer");
self = [super initWithFrame:frame];
if (self) {
// Initialization code
mybutton = [[UIButton alloc]initWithFrame:CGRectMake(frame.size.width/2,frame.size.height/2,20,20)];
[mybutton setTitle:#"b" forState:UIControlStateNormal];
[mybutton setTitle:#"b" forState:UIControlStateHighlighted];
self.backgroundColor = mycolor;
[self addSubview:mybutton];
}
return self;
}
and in my viewcontroller i am calling it as
p_subview1 = [[mysubview alloc] initWithbutton:CGRectMake(10,10,70,70) color:[UIColor blueColor]];
but during compilation i am getting error no visible interface in my subview class has this method plz consider if i am doing something silly here I am new to iphone development.
Related
I have created a custom UILabel class and set the default background color.
Here are .h and .m files of my custom class.
#import <UIKit/UIKit.h>
#interface imLabel : UILabel
#end
AND
#import "imLabel.h"
#implementation imLabel
- (void)drawRect:(CGRect)rect {
}
- (void) layoutSubviews {
self.backgroundColor = [UIColor redColor];
}
#end
It works fine, but here is what I need: I want this work only if the backgroundColor is not set in ViewController.
Here is my viewDidLoad
- (void)viewDidLoad {
[super viewDidLoad];
label = [[imLabel alloc] initWithFrame:CGRectMake(50, 50, 300, 300)];
label.backgroundColor = [UIColor blueColor];
[self.view addSubview:label];
}
You control whether set label's backgroundColor or not in ViewController, so the best way to meet your need that I think is check the label had set backgroundColor or not, if not then set it.
/* Somewhere in your ViewController */
if (!self.label.backgroundColor) {
self.label.backgroundColor = [UIColor redColor];
}
Delete all your other code in imLabel.m, then:-
(instancetype)initWithFrame:(CGRect)aRect { self = [super initWithFrame:aRect]; if (self) { self.backgroundColor = [UIColor redColor]; } return self;}
Thanks to #Meiliang Dong
I am not able to call the method which is written in UIViewController(aViewController) from my custom view bView .
I want to call the method function on my button(btn) click in UIView(bView). But when I click the button, i am getting the following error.
unrecognized selector sent to instance....
Here is my code:
aViewController.h
#import "bView.h"
#import "cViewController.h"
-(void)function;
aViewController.m
-(void)viewDidLoad{
bView = [[bView alloc]init];
[bView makeView];
bView.bViewController = self;
[self.view addSubView:bView];
}
-(void)function{
cViewController *nextViewController = [[cViewController alloc] initWithNibName: nil bundle: nil];
[self.navigationController pushViewController: nextViewController animated: YES];
}
bView.h
#import "bViewController.h"
#interface bView : UIView{
UIButton btn;
bView *BView;
}
-(void)makeView;
-(void)function;
#property (nonatomic,readonly) UIButton *btn;
#property (assign) UIViewController* aViewController;
bView.m
#import "bView.h"
#import "aViewController.h"
#impementation bView
#synthesize btn;
#synthesize aViewController;
-(void)makeView{
btn= [UIButton buttonWithType:UIButtonTypeRoundedRect];
UIImage *btnimg = [UIImage imageNamed:#"btn.png"];
[btn setBackgroundImage:btnimg forState:UIControlStateNormal];
btn.frame = CGRectMake(65, 380, 60, 60);
[self addSubview:btn];
btn.userInteractionEnabled = YES;
[btn addTarget:aViewController action:#selector(function) forControlEvents:UIControlEventTouchUpInside];
}
How to solve it?
You are setting a target to button in [bView makeView]; method, but at that time bView's aViewController is nil because you are setting it only on the next line. So try this:
-(void)viewDidLoad{
bView = [[bView alloc]init];
bView.bViewController = self;
[bView makeView];
[self.view addSubView:bView];
}
this is how you do it, first off, get rid of the "bView.bViewController = self", it doesn't work that way, you shouldn't do this, ever.
-(void)viewDidLoad {
bView = [[bView alloc]init];
[bView makeView];
[self.view addSubView:bView];
[[bView btn] addTarget:self action:#selector(function) forControlEvents:UIControlEventTouchUpInside];
}
function is declared in your UIViewController, not your UIView, so you must call to the button in your viewdidLoad through the bView and then assign it a target and action. I still wouldn't use this method that you are using, but this will do it.
this is the magic:
[[bView btn] addTarget:self action:#selector(function) forControlEvents:UIControlEventTouchUpInside];
AND, remove these lines from the UIView:
#property (assign) UIViewController* aViewController;
-(void)function;
[btn addTarget:aViewController action:#selector(function) forControlEvents:UIControlEventTouchUpInside];
you should remove these if your intent is for the UIViewController to have the function "-(void)function" and I assume this is what you meant. I'm assuming that your "function" is supposed to be called in your UIViewController
for out purposes here, this:
[[bView btn] addTarget:self action:#selector(function) forControlEvents:UIControlEventTouchUpInside];
is the same thing as this:
[bView.btn addTarget:self action:#selector(function) forControlEvents:UIControlEventTouchUpInside];
and
bView.btn = #property (nonatomic,readonly) UIButton *btn;
In fact, you don't need to call this button in any UIView, given what you are showing, just call this in your viewDidLoad, like this:
-(void)viewDidLoad
{
[super viewDidLoad];
UIButton * btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];
UIImage *btnimg = [UIImage imageNamed:#"btn.png"];
[btn setBackgroundImage:btnimg forState:UIControlStateNormal];
btn.frame = CGRectMake(65, 380, 60, 60);
btn.userInteractionEnabled = YES;
[self.view addSubview:btn];
[btn addTarget:self action:#selector(function) forControlEvents:UIControlEventTouchUpInside];
}
I'm showing you this because you aren't setting up the UIView correctly in the first place by invoking super on it's designated initializer so the best bet now is to just place the button in your viewDidLoad and move on, this is the solution until you understand how the initialize a UIView and set it up correctly. There's a lot of stuff that is wrong with the UIView you have set up and tried to subclass and it's going to be easier for you to just make the button in viewDidLoad and then learn how to subclass correctly in the future.
Related to this previous question (Creating UI elements programmatically in Objective-C), this method resides in one class of the project, and other classes are able to call it to programmatically create buttons:
UIButton *createButton(CGFloat x, CGFloat y, CGFloat width, CGFloat height, NSString *caption, NSTextAlignmentCenter textPosition, UIColor *textColor, UIColor *backColor) {
UIButton *control = [[UIButton alloc] initWithFrame: CGRectMake(x, y, width, height)];
[control setTitle:caption forState:UIControlStateNormal];
control.titleLabel.textAlignment = textPosition;
control.backgroundColor = backColor;
[control setTitleColor: textColor forState:UIControlStateNormal];
return control;
}
I am now trying to add the target and action methods, to be handled by a common function, like so:
[control addTarget:nil
action:#selector(commonHandler)
forControlEvents:UIControlEventTouchDown];
It works for buttons that reside in the same class as the createButton() function, but although the buttons are successfully created in the other classes as well, they don't trigger the commonHandler() method.
NOTE: the createButton() and commonHandler() methods have been declared in its header file, and imported by all classes.
Is there any way to achieve this?
EDIT: The proposed solution still crashes
I modified the code as per the suggestions, and converted both the createButton and buttonAction to Objective-C methods, to enable reference to self.
class1 header
// class1.h
#import <UIKit/UIKit.h>
#import "class2.h"
#interface class1 : UIViewController {
UIButton *button1;
}
- (void) buttonAction:(UIButton *)control;
- (UIButton *) createButtonWithxPos:(CGFloat)x
yPos:(CGFloat)y
width:(CGFloat)width
height:(CGFloat)height
caption:(NSString *)caption
textPos:(NSTextAlignment)textPosition
textClr:(UIColor *)textColor
backClr:(UIColor *)backColor;
#end
class1 implementation
// class1.m
#import "class1.h"
#import "class2.h"
#implementation class1
- (void)viewDidLoad {
[super viewDidLoad];
button1 = [self createButtonWithxPos:10
yPos:10
width:200
height:30
caption:#"Cls1 Button"
textPos:NSTextAlignmentCenter
textClr:[UIColor whiteColor]
backClr:[UIColor blackColor]];
[self.view addSubview: button1];
}
- (UIButton *) createButtonWithxPos:(CGFloat)x
yPos:(CGFloat)y
width:(CGFloat)width
height:(CGFloat)height
caption:(NSString *)caption
textPos:(NSTextAlignment)textPosition
textClr:(UIColor *)textColor
backClr:(UIColor *)backColor
{
UIButton *control = [[UIButton alloc] initWithFrame: CGRectMake(x, y, width, height)];
[control setTitle:caption forState:UIControlStateNormal];
control.titleLabel.textAlignment = textPosition;
control.backgroundColor = backColor;
[control setTitleColor: textColor forState:UIControlStateNormal];
[control addTarget:self action: #selector(buttonAction:) forControlEvents:UIControlEventTouchDown];
return control;
}
- (void) buttonAction:(UIButton *)control {
NSLog(#"button clicked...");
}
#end
class2 header
// class2.h
#import <UIKit/UIKit.h>
#interface class2 : UIViewController {
UIButton *button2;
}
#end
class2 implementation
// class2.m
#import "class1.h"
#import "class2.h"
#implementation class2
- (void) viewDidLoad {
[super viewDidLoad];
class1 *cls1 = [[class1 alloc] init];
button2 = [cls1 createButtonWithxPos:10
yPos:10
width:200
height:30
caption:#"Cls2 Button"
textPos:NSTextAlignmentCenter
textClr:[UIColor whiteColor]
backClr:[UIColor blackColor]];
[self.view addSubview: button2];
}
#end
Both button1 and button2 are created properly, but button1 triggers the buttonAction method while button2 does not - it crashes on touch.
Is it implemented wrongly?
(please excuse any omissions as I have only extracted the relevant portions from the actual project to illustrate here)
It seems like such a simple thing to remove a button from a view, but it is not working.
MyViewController.h
#import <UIKit/UIKit.h>
#interface MyViewController : UIViewController
#property (strong, nonatomic, readonly, getter = getMyButton) UIButton* myButton;
- (id) init;
- (id) getMyButton;
#end
MyViewController.m
#import "MyViewController.h"
#interface MyViewController ()
#end
#implementation MyViewController
#synthesize myButton = _myButton;
- (id) init
{
if([super initWithNibName: nil bundle: nil])
{
_myButton = nil;
}
return self;
}
- (id) getMyButton
{
if(!_myButton) _myButton = [self createMyButton];
return _myButton;
}
- (void) viewDidLoad
{
[super viewDidLoad];
UIButton* myButton = self.myButton;
[self.view addSubview: myButton];
}
- (void) didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
}
- (UIButton*) createMyButton
{
UIButton *button = [[UIButton alloc] init];
[button setTitle: #"My Button"
forState: UIControlStateNormal];
[button addTarget: self
action: #selector(myAction:)
forControlEvents: UIControlEventTouchUpInside];
button.frame = CGRectMake(10, 10, 100, 40);
return button;
}
- (void) myAction: (id) sender
{
[self.myButton performSelectorOnMainThread: #selector(removeFromSuperview) withObject: nil waitUntilDone: NO];
}
#end
But no luck. Clicking the button simply does nothing.
If it is not a problem of concurrency then maybe it is a memory management problem? Maybe it is just something daft, I don't know.
I tried putting the following line into the myAction method
NSLog(#"Test 1");
if(_startButton.superview) NSLog(#"Test 2");
Only 'Test 1' is logged. Perhaps that is a clue but what I don't know is why the button has no superview when it is added to view and is visible on the screen
Additional information
I don't know, if any of this is relevant, but maybe
I just updated Xcode to the latest version from the developer program (it supported up to iOS version 7.0 before, now 7.1)
I just started testing the app on an actual iPhone (I get the same problem testing with the simulator though)
Around the same time as this problem I also noticed that NSLog function doesn't work inside AppDelegate applicationHasLaunched method
Thanks
You didn't set the action for that button.
Change your createMyButton method like:
- (UIButton*) createMyButton
{
UIButton *button = [[UIButton alloc] init];
[button setTitle: #"My Button"
forState: UIControlStateNormal];
button.frame = CGRectMake(10, 10, 100, 40);
[button addTarget:self action:#selector(myAction:) forControlEvents:UIControlEventTouchUpInside];
return button;
}
Also change myAction method like:
- (void)myAction:(UIButton *)sender
{
[sender performSelectorOnMainThread: #selector(removeFromSuperview) withObject: nil waitUntilDone: NO];
}
Your code seems overly complicated:
Why do you need to lazy create the button?
Why does it need to be readonly?
Why do you need the performselector in your action?
I have taken the liberty to rewrite your code:
Header file
#property (nonatomic,strong) UIButton * button;
Code file
- (void)viewDidLoad
{
[super viewDidLoad];
self.button = [UIButton buttonWithType:UIButtonTypeSystem];
[self.button setTitle:#"MyButton" forState:UIControlStateNormal];
self.button.frame = self.view.bounds;
[self.button addTarget:self action:#selector(myAction:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:self.button];
}
-(void)myAction:(UIButton*)sender
{
[sender removeFromSuperview];
}
Happy coding!
Edit
If you insist on going with your original code, try changing
- (id) getMyButton
to
-(UIButton*)myButton
Buttons are a class family and should be created with [UIButton buttonWithType:]
I am sure that your myAction is not get fired. Cause you forget to addTarget
on your createMyButton method just add one more line
[button addTarget:self action:#selector(myAction:) forControlEvents:UIControlEventTouchUpInside];
UPDATE: You've also marked this question as iOS but you are importing OSX headers
#import "NSViewController.h"
#interface MyViewController: NSViewController
you should be inheriting from UIViewController
#import <UIKit/UIKit.h>
#interface MyViewController : UIViewController
Are you creating the view controller via the init code you've posted?
- (id) init
{
if([super initWithNibName: nil bundle: nil])
{
_myButton = nil;
}
return self;
}
Here you are not allocating anything to self the code should be
- (id) init
{
self = [super initWithNibName: nil bundle: nil];
if(self)
{
_myButton = nil;
}
return self;
}
I have a view controller (UserLogin) that calls a method in NSObject class (custompop). The method returns a UIView object to viewController. In method i add one button and call action popupAction on button click. The popupAction calls method in view controller. I set all the delegate property.
Here is the code:
//**in viewcontroller.h**
#import "custompopup.h"
#interface UserLogin : UIViewController<customPopUpDelegate>
{
custompopup *obj_custompopup;//NSObject Class
}
-(void)handlePopUpAction;
//**in viewcontroller.m**
- (void)viewDidLoad
{
[super viewDidLoad];
obj_custompopup = [[custompopup alloc] init];
[obj_custompopup setDelegate:self];
popupview = [[UIView alloc] init];
popupview = [obj_custompopup initwithTitleText:#"Title" withdelegate:self];
[self.view addSubview:popupview];
}
-(void)handlePopUpAction
{
NSLog(#"Inside handlePopUpAction");
}
//**in NSObject.h**
#protocol customPopUpDelegate <NSObject>
-(void)handlePopUpAction;
#end
#interface custompopup : NSObject
{
id<customPopUpDelegate>delegate;
UIButton *First_Btn;
}
#property(retain)id delegate;
//**in NSObject.m**
#synthesize delegate;
-(UIView *)initwithTitleText:(NSString *)titleText withdelegate:(id)del
//returns uiview to viewcontroller
{
self.delegate =del;
UIView *customView = [[UIView alloc] init];
customView.frame = CGRectMake(200, 100, 617,367);
First_Btn =[UIButton buttonWithType:UIButtonTypeRoundedRect];
First_Btn.frame=CGRectMake(20, 330,125,45);
[First_Btn #"title" forState:UIControlStateNormal];
[First_Btn addTarget:self action:#selector(popUpAction) forControlEvents:UIControlEventTouchUpInside];
[customView addSubview:First_Btn];
return customView;
}
-(void)popUpAction
{
[[self delegate] handlePopUpAction];
}
Problem is compiler goes in each method successfully and print everything in console till last step. After complete last step in view controller, EXC_BAD_ACCESS comes and the application crashes.
your init is wrong .. dont get what you try to do but you return customView , leaving self unretained but you are using self.