I have a Table View with APParallaxHeader. This creates a view behind the table, which acts as the header of it. My problem is, that I cannot click anything in this header. I've tried overriding -hitTest of the UITableView, but had no success.
Here is my view controller:
#import "TableViewController.h"
#import "UIScrollView+APParallaxHeader.h"
#implementation TableViewController
- (void)viewDidLoad
{
[super viewDidLoad];
UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 320, 320)];
[button setTitle:#"Hello" forState:UIControlStateNormal];
[button setBackgroundColor:[UIColor redColor]];
[button addTarget:self action:#selector(ping) forControlEvents:UIControlEventTouchUpInside];
[self.tableView addParallaxWithView:button andHeight:320];
}
- (void)ping
{
NSLog(#"%s", __PRETTY_FUNCTION__);
}
#end
EDIT:
My further investigation shows, that the problem can be reduced to a simple UIButton below a UITableView. How can you get the tap events with the button?
Related
I'm trying to generate a class that can create a UIButton and take care of what happens when you press the button in any view where the button is located. Here is what I'm doing:
Header File:
#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>
#interface CreateButton : NSObject
- (UIButton *)createButton;
#end
Implementation:
#import "CreateButton.h"
#implementation CreateButton
- (UIButton *)createButton
{
// Instanciate the class
CreateButton *classInstance = [[CreateButton alloc] init];
UIButton *testButton = [[UIButton alloc] initWithFrame:CGRectMake(0.0, 0.0, 50.0, 50.0)];
[testButton setBackgroundColor:[UIColor redColor]];
[testButton addTarget:classInstance action:#selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
return testButton;
}
- (void)buttonClicked:(UIButton *)sender
{
NSLog(#"Clicked");
}
#end
And finally, in the a view controller, I initialize the class and get the button:
CreateButton *create = [[CreateButton alloc] init];
UIButton *testButton = [create createButton];
[self.view addSubview:testButton];
Now everything is ok up to this point and I can see the button, however, nothing happens when I click it. Surprisingly, if I move the buttonClicked: method to my view controller it works just fine. I need to keep all the button wiring inside the NSObject. Any help would be greatly appreciated.
Ok, I solved the problem, interesting.
Implementation file will be modified as:
- (UIButton *)createButton
{
UIButton *testButton = [[UIButton alloc] initWithFrame:CGRectMake(0.0, 0.0, 50.0, 50.0)];
[testButton setBackgroundColor:[UIColor redColor]];
[testButton addTarget:self action:#selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
return testButton;
}
Then, in the view controller, CreateButton class must be pre-defined in the header file #interface section. Then in the implementation:
create = [[CreateButton alloc] init];
and it works! That would be great if you kindly explains this to me.
I am trying to use Objective-C in iOS Single View app to program a UIButton to change the text in a UILabel. Is there a way to run a function for this to be implemented in my "ViewController.m" file?
Here is my Source Code:
#import "ViewController.h"
#interface ViewController ()
#end
#implementation ViewController
- (void)loadView {
//UIBUTTON
//allocate the view
self.view = [[UIView alloc] initWithFrame:[[UIScreen mainScreen] applicationFrame]];
//set the view's background color
self.view.backgroundColor = [UIColor whiteColor];
//create the button
UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
//set the position of the button
button.frame = CGRectMake(50, 280, 280, 50);
//set the font size of the button
button.titleLabel.font = [UIFont systemFontOfSize:40];
//set the text color of the button, before it is pressed
[button setTitleColor:[UIColor blueColor] forState:UIControlStateNormal];
//set the text color of the button, while it is pressed
[button setTitleColor:[UIColor grayColor] forState:UIControlStateHighlighted];
//set the button's title
[button setTitle:#"3" forState:UIControlStateNormal];
//listen for clicks
[button addTarget:self action:#selector(buttonPressed)
forControlEvents:UIControlEventTouchUpInside];
//add the button to the view
[self.view addSubview:button];
//UILABEL
UILabel *Question=[ [UILabel alloc] initWithFrame:CGRectMake(10,200,350,60)];
Question.text=#"How many horns does a Triceratops have?";
Question.backgroundColor = [UIColor grayColor];
Question.textColor = [UIColor whiteColor];
Question.font=[UIFont fontWithName:#"Helvetica" size:18 ];
[self.view addSubview:Question];
}
-(void)buttonPressed { }
#end
Is it possible to trigger the change in text in my buttonPressed function? Thanks so much for anybody's help!
The problem is that when you create your label and add it to the interface...
UILabel *Question=[ [UILabel alloc] initWithFrame:CGRectMake(10,200,350,60)];
// ...
[self.view addSubview:Question];
...you didn't keep a reference to it. So now, in buttonPressed, you have no way to talk about the label.
Make a property:
#interface ViewController ()
#property (nonatomic, weak) UILabel* questionLabel;
#end
... and when you create the label, remember to set that property to that label. Now you will be able to access the text of that label later on, in buttonPressed (or anywhere else), through the property.
I'm just adding a quick intro screen with a button, which compiles and displays properly, but my button doesn't respond.
- (void)viewDidLoad {
[super viewDidLoad];
NSLog(#"viewDidLoad!");
[self showIntro];
}
// make a quick Intro screen
- (void) showIntro {
UIImageView *myBackImage = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 320, 460)];
[myBackImage setImage:(UIImage *) [UIImage imageNamed:#"myBkgnd.png"]];
UIButton *clickBtn = [UIButton buttonWithType:UIButtonTypeCustom ];
[clickBtn addTarget:self action:#selector(myButton_pressed:) forControlEvents:UIControlEventTouchUpInside];
[clickBtn setImage:(UIImage *) [UIImage imageNamed:#"btnImage.png"] forState:UIControlStateNormal];
clickBtn.frame = CGRectMake(111, 200, 75, 60);
[myBackImage addSubview:clickBtn];
[self.view addSubview:myBackImage];
}
- (void)myButton_pressed:(UIButton*)button {
NSLog(#"Button Pressed!");
}
What am I overlooking?
Thanks!
As you have added UIButton in UIImageView but didn't you forgot imageView's userInteraction by default NO. So :
myBackImage.userInteractionEnabled = YES;
EDIT : Just formatted
I have a iOS5 project using storyboard and with ARC on.
I have a view in storyboard with the class thisViewController and in there I got a smaller subview which I dragged in and gave it the class thisView.
thisView has a custom drawRect function, that works and draws what I want nicely.
But I also want to add buttons dynamically, so I'll add them in the initWithFrame method of thisView like so:
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
NSLog(#"This is called <3");
UIButton *btn= [UIButton buttonWithType:UIButtonTypeRoundedRect];
btn.frame = CGRectMake(0, 0, 50, 50);
btn.backgroundColor = [UIColor redColor];
[btn setTitle:#"Play" forState:UIControlStateNormal];
[btn addTarget:self action:#selector(buttonClick) forControlEvents:UIControlEventTouchUpInside];
[self addSubview:btn];
[self bringSubviewToFront:btn]; // last thing I tried, didn't work, thought z-index was to low or something
}
return self;
}
The function is being called since the NSLog displays, but the button is nowhere to be found
--EDIT--
Extra information:
ThisView.h
#interface RadarView : UIView <CLLocationManagerDelegate>{
CLLocation *currentLocation;
}
Dont add the SubView in the init method.
Add the SubView in the - (void)layoutSubviews.
- (void)layoutSubviews {
[super layoutSubviews];
if (![self viewWithTag:12345]) {
UIButton *btn= [UIButton buttonWithType:UIButtonTypeRoundedRect];
btn.frame = CGRectMake(0, 0, 50, 50);
btn.tag = 12345;
btn.backgroundColor = [UIColor redColor];
[btn setTitle:#"Play" forState:UIControlStateNormal];
[btn addTarget:self action:#selector(buttonClick) forControlEvents:UIControlEventTouchUpInside];
[self addSubview:btn];
}
}
I found what the problem was thanks to some comments and the chat
There was an init in the radarviewcontroller, which triggered initwithframe, which made the NSLog display, and the initwithcoder wasn't used so I didn't see anything, that was the problem and got stuff mixed up. Thanks for commenting and helpin!
I have a view with a generic rounded rect button that segues to another view. When users press the rounded rect it starts a fetch. I would like to have a spinning wheel replace the text ("Next") inside the rounded rect button while the fetch is processed.
I created the spinner:
UIActivityIndicatorView *spinner = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
[spinner startAnimating];
But I don't know how to make it replace the text in the rounded rect button.
Any suggestion? Thank you.
Create (or get a reference to) the button as usual, then, while handling the button click, create your spinner and set it as a subview of the button. It's probably also worth disabling the button to stop multiple clicks.
Something along the following lines should do the trick:
...
UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
button.frame = CGRectMake(10, 10, 70, 40);
[button setTitle:#"Next" forState:UIControlStateNormal];
[button addTarget:self action:#selector(click:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:button];
...
- (void)click:(UIButton *)button {
[button setTitle:#"" forState:UIControlStateNormal];
UIActivityIndicatorView *spinner = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
[spinner startAnimating];
spinner.frame = button.bounds;
[button addSubview:spinner];
button.enabled = NO;
// do your actual work...
}
I wrote a category that utilizes associated objects
UIButton+ActivityIndicator.h
// Created by reynaldo on 1/16/14.
#import <Foundation/Foundation.h>
#interface UIButton (ActivityIndicator)
- (void)startActivityIndicator;
- (void)stopActivityIndicator;
#end
UIButton+ActivityIndicator.m
// Created by reynaldo on 1/16/14.
#import <objc/runtime.h>
#import "UIButton+ActivityIndicator.h"
static char TITLE_KEY;
static char ACTIVITY_INDICATOR_KEY;
#implementation UIButton (ActivityIndicator)
- (void)startActivityIndicator {
objc_setAssociatedObject(self, &TITLE_KEY, self.currentTitle, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
[self setTitle:#"" forState:UIControlStateNormal];
UIActivityIndicatorView *activityIndicatorView = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhite];
[self addSubview:activityIndicatorView];
activityIndicatorView.frame = CGRectMake(self.frame.size.width / 2, self.frame.size.height / 2. - 2, 7, 7);
[activityIndicatorView startAnimating];
objc_setAssociatedObject(self, &ACTIVITY_INDICATOR_KEY, activityIndicatorView, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}
- (void)stopActivityIndicator {
NSString *title = objc_getAssociatedObject(self, &TITLE_KEY);
UIActivityIndicatorView *activityIndicatorView = objc_getAssociatedObject(self, &ACTIVITY_INDICATOR_KEY);
if(activityIndicatorView) {
[activityIndicatorView removeFromSuperview];
}
if(title.length) {
[self setTitle:title forState:UIControlStateNormal];
}
}
#end