I'm try to add a scrollview totally by code to a modal view, but it doesn't show.
I've tried different ways but I can't see the mistake,
Somebody could help me?
here my code:
#interface AddWithScrollOrizontal ()<UIScrollViewDelegate>{
//IBOutlet UIScrollView*scroll;
}
#property (strong, nonatomic) UIScrollView*scroll;
#implementation AddWithScrollOrizontal
#synthesize scroll;
- (void)viewDidLoad
{
self.scroll = [[UIScrollView alloc]init];
self.scroll.delegate = self;
if (IS_IPHONE_5) {
self.scroll.frame = CGRectMake(0, 58, 320, 270);
}else{
self.scroll.frame = CGRectMake(0, 20, 320, 270);
}
self.scroll.backgroundColor = [UIColor redColor];
self.scroll.pagingEnabled = YES;
self.scroll.contentSize =CGSizeMake(1280, 270);
UIView*firstView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 320, 270)];
...
UIView*fourthView = [[UIView alloc]initWithFrame:CGRectMake(960, 0, 320, 270)];
[self.scroll addSubview:firstView];
[self.scroll addSubview:secondView];
[self.scroll addSubview:thirdView];
[self.scroll addSubview:fourthView];
[self.view addSubview:self.scroll];
}
You say you're adding it totally by code, but you're making an IBOutlet to scroll. Did you create it in IB? If not, your problem is that you never instantiate the scroll view. Also, there's no need to create an ivar for scroll, just create the property inside the #interface declaration for your class extension, and refer to it with self.scroll.
Related
How to achieve the below design in iOS , is any controls available to achieve this. I am not that much experienced to achieve this design in native . Is it developed in native or kind of hybrid technology is used
Please find the below image for reference
I made a programmatic Example (Kind of "Hello World") for you
(it is programatic for a reason, that I believe it is easier to understand how things are working.
It is not perfect solution it can be done better, (performance wise) but I choose it as a simple example to get you started (Personally I would use CALayer for the backgrounds).
so here:
make a new class as follows:
MyView.h
#import <UIKit/UIKit.h>
#interface MyView : UIView
#end
MyView.m
#import "MyView.h"
#implementation MyView
- (instancetype)initWithFrame:(CGRect)frame
{
if(self = [super initWithFrame:frame])
{
self.backgroundColor = [UIColor grayColor];
//This rect is in self coordinate system
UIView * viewPurple = [[UIView alloc]initWithFrame:CGRectMake(0, 200, frame.size.width, 50)];
viewPurple.backgroundColor = [UIColor purpleColor];
[self addSubview:viewPurple];
//This rect is in viewPurple's coordinate system
UILabel * label = [[UILabel alloc]initWithFrame:CGRectMake(0, 0, frame.size.width/2, 50)];
[label setText:#"Hello World!"];
[label setTextAlignment:(NSTextAlignmentCenter)];
[label setTextColor:[UIColor whiteColor]];
[viewPurple addSubview:label];
//All the frame's rects are in it's `superView`/ parent 's coordinate system.
UIView * viewGreen = [[UIView alloc]initWithFrame:CGRectMake(frame.size.width/2, 200, frame.size.width, 50)];
viewGreen.backgroundColor = [UIColor cyanColor];
[self addSubview:viewGreen];
UILabel * label2 = [[UILabel alloc]initWithFrame:CGRectMake(0, 0, frame.size.width/2, 50)];
[label2 setText:#"World Hello!"];
[label2 setTextAlignment:(NSTextAlignmentCenter)];
[label2 setTextColor:[UIColor whiteColor]];
[viewGreen addSubview:label2];
}
else
{
//Can't allocate the UIView - quite a rare problem.
}
return self;
}
#end
#import "myView.h" in your view controller
and add this snippet to the - (void)viewDidLoad method.
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
MyView * view = [[MyView alloc]initWithFrame:self.view.frame];
[self.view addSubview:view];
}
the result will be as follow
I create a tableView in a class inherit from UIView.It works well when I add a button at tableFooterView on this tableView.
CustomView.h
#import <UIKit/UIKit.h>
#interface CustomView : UIView<UITableViewDelegate,UITableViewDataSource>
#end
CustomView.m
- (UIView *)tableView:(UITableView *)tableView viewForFooterInSection:(NSInteger)section{
UIView * customView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.bounds.size.width, 80)];
UIButton * tempButton = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 100, 40)];
tempButton.center = customView.center;
tempButton.backgroundColor = [UIColor redColor];
[tempButton addTarget:self action:#selector(doButtonAction) forControlEvents:UIControlEventTouchUpInside];
[customView addSubview:tempButton];
return customView;
}
- (void)doButtonAction{
NSLog(#"123");
}
NSLog:123
However,I public this button and make a target-action in my controller.It response nothing.
CustomView.h
#property (strong, nonatomic) UIButton * tempButton;
CustomView.m
- (UIView *)tableView:(UITableView *)tableView viewForFooterInSection:(NSInteger)section{
UIView * customView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.bounds.size.width, 80)];
self.tempButton = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 100, 40)];
self.tempButton.center = customView.center;
[customView addSubview:self.tempButton];
return customView;
}
ViewController.h
- (void)viewDidLoad {
[super viewDidLoad];
CustomView *cv = [[CustomView alloc] initWithFrame:self.view.bounds ];
[cv.tempButton addTarget:self action:#selector(doButtonAction) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:cv];
}
- (void)doButtonAction{
NSLog(#"123");
}
what did I miss?
In the viewdidload you are not set any thing on the button,
You just assign in the #interface.
but you must be alloc and set the frame and backgroundcolor and all properties on the button in the viewdidload .
After that it will work.
May be it will help you or feel free.
I described [self.view addSubView:myView];,
but, myView is not displaying self.view.
ViewController.h
#interface ViewController : UIViewController{
UIView *myView;
}
#property (nonatomic, strong) UIView *myView;
ViewController.m
#synthesize myView;
- (void)viewDidLoad
{
[super viewDidLoad];
myView.frame = CGRectMake(-10, 70, 320, 480);
[self.view addSubview:myView];
myView.backgroundColor = [UIColor redColor];
[self.view bringSubviewToFront:myView];
}
Do you have any solutions?
You need to allocate your view first:
- (void)viewDidLoad
{
[super viewDidLoad];
// If you use custom view change UIView to the custom class name
myView = [[UIView alloc] initWithFrame:CGRectMake(-10, 70, 320, 480)];
[self.view addSubview:myView];
myView.backgroundColor = [UIColor redColor];
[self.view bringSubviewToFront:myView];
}
I have a method were I'm creating UIView and it works fine when I call it from IBAction. But when I call the same method again it draws another view on top and I believe it's a memory leak. How do I remove previous UIView before creating another one? Thanks!
- (int)showQuestionMethod:(int)number;
{
UIView *questionView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 500, 250)];
questionView.backgroundColor = [[UIColor alloc] initWithRed:0.93 green:0.93
blue:0.93 alpha:1.0];
[self.view addSubview:questionView];
questionView.tag = questionNumber;
UILabel *questionLabel = [[UILabel alloc] initWithFrame:CGRectMake(20, 20, 280, 0)];
questionLabel.text = question1;
[questionView addSubview:questionLabel];
CGRect frame = questionView.frame;
frame.size.height = questionHeight;
questionView.frame = frame;
questionView.tag = questionNumber;
return currentQuestion;
}
- (IBAction)nextQuestion:(id)sender {
[self showQuestionMethod:questionNumber];
}
Create a property which will let you reference a view:
#property(nonatomic, strong) UIView *questionView;
Then change your method to remove the old view and create a new one:
- (int)showQuestionMethod:(int)number;
{
// Remove the previous view.
[_questionView removeFromSuperview];
// Create a new view.
_questionView= [[UIView alloc] initWithFrame:CGRectMake(0, 0, 500, 250)];
_questionView.backgroundColor = [[UIColor alloc] initWithRed:0.93 green:0.93
blue:0.93 alpha:1.0];
// Add the view.
[self.view addSubview:_questionView];
_questionView.tag = questionNumber;
UILabel *questionLabel = [[UILabel alloc] initWithFrame:CGRectMake(20, 20, 280, 0)];
questionLabel.text = question1;
[_questionView addSubview:questionLabel];
CGRect frame = _questionView.frame;
frame.size.height = questionHeight;
_questionView.frame = frame;
_questionView.tag = questionNumber;
return currentQuestion;
}
The simplest way would be to keep a reference to the view you will want to remove (a private property would work nicely). You could add the code at bottom to the top of your controllers .m file:
#interface MyUIViewController ()
#property (nonatomic, strong) UIView* questionView;
#end
Then modify your method as follows:
- (int)showQuestionMethod:(int)number;
{
[self.questionView removeFromSuperview]
self.questionView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 500, 250)];
self.questionView.backgroundColor = [[UIColor alloc] initWithRed:0.93 green:0.93
blue:0.93 alpha:1.0];
[self.view addSubview:self.questionView];
self.questionView.tag = questionNumber;
UILabel *questionLabel = [[UILabel alloc] initWithFrame:CGRectMake(20, 20, 280, 0)];
self.questionLabel.text = question1;
[self.questionView addSubview:questionLabel];
CGRect frame = questionView.frame;
frame.size.height = questionHeight;
self.questionView.frame = frame;
self.questionView.tag = questionNumber;
return currentQuestion;
}
use this before creating new view
[myview removeFromSuperview];
You can either keep a reference to the view by adding #property (strong, nonatomic) UIView *questionView; in your #interface declaration then call [_questionView removeFromSuperview]; to remove it.
Or, better yet, keep that reference to it then have a method to reload the info on it and animate it out/back into view (perhaps by fading out, reloading the data on it, then fading it back in). That way you aren't throwing away / recreating views all the time, and instead you're just reusing the same, already created view.
[self.questionView removeFromSuperview];
before adding the other view, remove this from the superview!
Why not reuse the view?
If you'd rather delete it every time and you don't want to keep a reference to it, you can always set (dirty but simple):
questionView.tag = SOME_CONST;
And then add in the beginning of your method:
[[self.view viewWithTag:SOME_CONST] removeFromSuperview];
I know this question has been answered, but i want to add a precaution that you before removing a UIView or anything else you should FIRST CHECK IF IT IS ALLOCATED. So the removal should be like:
// Make property first
#property (nonatomic, strong) UIView *questionView;
- (int)showQuestionMethod:(int)number;
{
// Check it it is allocated
if(questionView)
{
[questionView removeFromSuperView];
//[questionView release]; // Un-Comment it if NOT using ARC
questionView = nil;
}
// At this point you safe to create a new UIView.
questionView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 500, 250)];
questionView.backgroundColor = [[UIColor alloc] initWithRed:0.93 green:0.93
blue:0.93 alpha:1.0];
[self.view addSubview:questionView];
questionView.tag = questionNumber;
UILabel *questionLabel = [[UILabel alloc] initWithFrame:CGRectMake(20, 20, 280, 0)];
questionLabel.text = question1;
[questionView addSubview:questionLabel];
CGRect frame = questionView.frame;
frame.size.height = questionHeight;
questionView.frame = frame;
questionView.tag = questionNumber;
return currentQuestion;
}
Hope the snippet and comment inside makes sense.
Happy Coding!!!
I have set my scrollView only on a part of the screen.
UIScrollView *scrollView=[[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, 320, 500)];
scrollView.contentSize=CGSizeMake(320,1500);//568
[self.view addSubview:scrollView];
Also, out of the scrollView I have set a button.
UIButton *hintbtn = [[UIButton alloc] initWithFrame:CGRectMake(160,self.view.frame.size.height - 50,160,50)];
[hintbtn addTarget:self action:#selector(hint:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:hintbtn];
If you press this button, I want to make the scrollView to scroll down.
-(void)hintbtn:(UIButton*)button {
[scrollView setContentOffset:CGPointMake(0, self.view.frame.size.height - 50) animated:YES];
}
However, it gives an error saying "unknown receiver 'scrollView'". Is there a way to fox this?
Please help me, how to deal with this problem.
That's happening because you don't have a reference to your scrollview variable. To fix the issue please do the following:
In your class' header file (The *.h file) add the following:
#interface YOUR_CLASS_NAME : UIViewController
// Add the following line to the header file
#property (nonatomic, strong) UIScrollView *scrollView;
#end
Then, in the implementation file (The *.m file) add the following:
// Wherever you have this code. It's probably in 'viewDidLoad'
self.scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, 320, 500)];
self.scrollView.contentSize=CGSizeMake(320,1500);//568
[self.view addSubview:self.scrollView];
// In the following line you have a typo. The selector should be "hintbtn:"!
[hintbtn addTarget:self action:#selector(hintbtn:) forControlEvents:UIControlEventTouchUpInside];
// Also modify this code:
-(void)hintbtn:(UIButton*)button {
[self.scrollView setContentOffset:CGPointMake(0, self.view.frame.size.height - 50) animated:YES];
}
Let me know if you have more questions.
Hope this helps!