I'm trying to position a button so that it is always an X amount of pixels from the bottom of the screen. The view is laid out programmatically using auto layout. If I use: #"V:|-44-[closeModalButton]" the object aligns 44 pixels from the top of the screen as expected. However, #"V:[closeModalButton]-44-|" causes the button to never show up. It seems like it ought to be pretty straightforward, so I feel like I'm missing something really obvious.
Implementation of view
#import "DetailView.h"
#implementation DetailView
#synthesize closeModalButton;
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
self.backgroundColor = [UIColor whiteColor];
CGRect aFrame = [[UIScreen mainScreen] bounds];
self.frame = aFrame;
closeModalButton = [UIButton buttonWithType:UIButtonTypeCustom];
[closeModalButton setImage: [UIImage imageNamed:#"closeButton.png"] forState:UIControlStateNormal];
[closeModalButton setTranslatesAutoresizingMaskIntoConstraints:NO];
[self addSubview:closeModalButton];
NSDictionary *viewArranging = NSDictionaryOfVariableBindings(closeModalButton);
[self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:#"V:[closeModalButton(44)]-44-|"
options:0
metrics:0
views:viewArranging]];
[self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:#"H:|-149-[closeModalButton(44)]-149-|"
options:0
metrics:0
views:viewArranging]];
}
return self;
}
#end
View controller
#import "DetailViewController.h"
#interface DetailViewController ()
#end
#implementation DetailViewController
{
DetailView *_detailView;
}
- (void)loadView
{
_detailView = [[DetailView alloc] init];
[self setView:_detailView];
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.
[_detailView.closeModalButton addTarget:self
action:#selector(closeModalButtonPressed:)
forControlEvents:UIControlEventTouchUpInside];
}
- (void)closeModalButtonPressed:(UIButton *)sender{
[self dismissViewControllerAnimated:YES
completion:nil];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#end
Ok, so it looks like DetailView.h subclassed UIScrollView rather than UIView. Setting the proper subclass caused the constraints to operate as expected.
Related
I have a custom UIView with a UICollectionView.
On screen rotation I am trying to get the UICollectionView to stretch across the screen, and then redraw its cells.
After I had the data downloaded I tried both [grid setNeedsLayout] and [grid setNeedsDisplay] but that didn't work.
This is what I want to happen:
Portrait
Landscape
(This is also how it appears when the app is started in landscape, but if you change to portrait it doens't update.)
But this is what I get if I start in Portrait mode and switch to Landscape.
I am creating these views programmatically. I am not using any Storyboards.
I have tried:
-(void)viewDidLayoutSubviews {
grid = [[MyThumbnailGridView alloc] initWithFrame:CGRectMake(0, self.view.frame.size.height/2, self.view.frame.size.width, self.view.frame.size.height/2)];
}
I have also tried toying with:
- (void) viewWillLayoutSubviews {
UIInterfaceOrientation interfaceOrientation = [[UIApplication sharedApplication] statusBarOrientation];
if (UIInterfaceOrientationIsLandscape(interfaceOrientation))
{
//LANDSCAPE
if(grid){
NSLog(#"Grid Needs Landscape Layout");
grid.frame =CGRectMake(0, self.view.frame.size.height/2, self.view.frame.size.width, self.view.frame.size.height/2);
[grid refreshData];
}
}else {
//PORTRIAT
if(grid){
NSLog(#"Grid Needs Portrait Layout");
grid.frame =CGRectMake(0, self.view.frame.size.height/2, self.view.frame.size.width, self.view.frame.size.height/2);
[grid refreshData];
}
}
}
But I can't get it to stretch.
Any help?
MyThumbnailGridView
#interface ViewController () <UINavigationControllerDelegate> {
MyThumbnailGridView *grid;
NSMutableArray * arrImages;
}
- (void)viewDidLoad {
[super viewDidLoad];
arrImages = [NSMutableArray new];
grid = [[MyThumbnailGridView alloc] initWithFrame:CGRectMake(0, self.view.frame.size.height/2, self.view.frame.size.width, self.view.frame.size.height/2)];
//grid = [[MyThumbnailGridView alloc] initWithFrame:CGRectZero];
NSLog(#"showThumbnailGrid Grid View Size: %#", NSStringFromCGRect(grid.frame));
[self.view addSubview:grid];
[self getListOfImages];
}
-(void) getListOfImages {
//Do background task to get images and fill arrImages
[self onDownloadImageDataComplete];
}
- (void) onDownloadImageDataComplete{
grid.imageDataSource = arrImages;
// [grid setNeedsLayout];
// [grid setNeedsDisplay];
}
//...
#end
*MyThumbnailGridView.h
#interface MyThumbnailGridView : UIView
-(id)initWithFrame:(CGRect)frame;
-(void) refreshData;
#property (nonatomic,strong) NSArray *imageDataSource;
#end
*MyThumbnailGridView.m
#interface MyThumbnailGridView () <UICollectionViewDelegate, UICollectionViewDataSource>{
UICollectionView *collectionView;
}
#end
#implementation MyThumbnailGridView
- (instancetype) initWithFrame:(CGRect)frame {
self = [super initWithFrame:frame];
if(self){
[self customInit];
}
return self;
}
- (void) customInit {
collectionView = [[UICollectionView alloc] initWithFrame:self.bounds collectionViewLayout:[[MyFlowLayout alloc] init]];
collectionView.delegate = self;
collectionView.dataSource = self;
collectionView.allowsMultipleSelection = NO;
collectionView.showsVerticalScrollIndicator = YES;
[collectionView setBackgroundColor:[UIColor darkGrayColor]];
[collectionView registerClass:[MyCollectionViewCell class] forCellWithReuseIdentifier:#"MyId"];
[self addSubview:collectionView];
}
- (void) refreshData {
NSLog(#"Refresh Grid Data");
[collectionView reloadData];
}
////other code
#end
MyFlowLayout
#interface MyFlowLayout : UICollectionViewFlowLayout
#end
#implementation MyFlowLayout
- (instancetype)init{
self = [super init];
if (self)
{
self.minimumLineSpacing = 1.0;
self.minimumInteritemSpacing = 1.0;
self.scrollDirection = UICollectionViewScrollDirectionVertical;
}
return self;
}
- (CGSize)itemSize {
NSInteger numberOfColumns = 3;
CGFloat itemWidth = (CGRectGetWidth(self.collectionView.frame) - (numberOfColumns - 1)) / numberOfColumns;
return CGSizeMake(itemWidth, itemWidth);
}
#end
MyCollectionViewCell
#interface MyCollectionViewCell : UICollectionViewCell
#property (strong, nonatomic) UIImageView *imageView;
#end
#implementation MyCollectionViewCell
- (instancetype)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
self.imageView = [UIImageView new];
[self.imageView setContentMode:UIViewContentModeScaleAspectFill];
[self.imageView setClipsToBounds:YES];
[self.imageView setBackgroundColor:[UIColor darkGrayColor]];
[self.contentView addSubview:self.imageView];
}
return self;
}
- (void)prepareForReuse {
[super prepareForReuse];
self.imageView.image = nil;
[self.imageView setHidden:NO];
}
- (void)layoutSubviews {
[super layoutSubviews];
[self.imageView setFrame:self.contentView.bounds];
}
#end
This can be solved with
either you can change the frame of MyThumbnailGridView view in delegate function of orientation or create the view with constraints like this
(void)viewDidLoad {
[super viewDidLoad];
arrImages = [NSMutableArray new];
grid = [[MyThumbnailGridView alloc] initWithFrame:CGRectMake(0, self.view.frame.size.height/2, self.view.frame.size.width, self.view.frame.size.height/2)];
[self.view addSubview:grid];
[self getListOfImages];
}
-(void)viewDidLayoutSubviews
{
if(Once){
Once = NO;
// adding constraints
MyThumbnailGridView.translatesAutoresizingMaskIntoConstraints = NO;
[self.MyThumbnailGridView.widthAnchor constraintEqualToConstant:self.view.frame.size.width].active = YES;
[self.MyThumbnailGridView.heightAnchor constraintEqualToConstant:self.view.frame.size.height/2].active = YES;
[self.MyThumbnailGridView.leadingAnchor constraintEqualToAnchor:self.view.leadingAnchor].active = YES;
[self.MyThumbnailGridView.topAnchor constraintEqualToAnchor:self.view.topAnchor constant:self.view.frame.size.height/2].active = YES;
}
}
Also implement this
- (void)viewWillTransitionToSize:(CGSize)size withTransitionCoordinator:(id<UIViewControllerTransitionCoordinator>)coordinator
{
[self.view layoutIfNeeded];
[MyThumbnailGridView.collectionView invalidate];
// Do view manipulation here.
[super viewWillTransitionToSize:size withTransitionCoordinator:coordinator];
}
The problem is that the collection view itself is not changing size when the app rotates. You have given the collection view a fixed frame and then just walked away. So it never changes. So never lays itself out again.
You should give your MyThumbnailGridView and its collection view subview autolayout contraints to their superviews, so that they change size correctly when the app rotates.
My problem with after pinch zoom, when I pinch zoom and after drag image then white space on top and bottom.
My Code as per apple documentation.
https://developer.apple.com/library/content/documentation/WindowsViews/Conceptual/UIScrollView_pg/ZoomZoom/ZoomZoom.html
Sample code
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view.
scrollView.minimumZoomScale=0.5;
scrollView.maximumZoomScale=6.0;
scrollView.contentSize=CGSizeMake(1280, 960);
scrollView.delegate = self;
}
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView
{
return imageView;
}
Thank you.
At first set your minimum zoom scale to 1.0:
scrollView.minimumZoomScale = 1.0;
Next, set the contentSize for scrollView:
scrollView.contentSize = [UIScreen mainScreen].bounds.size;
And if you don't want to see the extra space when bouncing, add the next line:
scrollView.bounces = NO;
Completely, the method should looks something like this:
- (void)viewDidLoad
{
[super viewDidLoad];
self.scrollView.minimumZoomScale = 1.0;
self.scrollView.maximumZoomScale = 6.0;
self.scrollView.bounces = NO;
self.scrollView.contentSize = [UIScreen mainScreen].bounds.size;
self.scrollView.delegate = self;
}
Hope it will help.
This is how I do it. If you image fits perfectly into the view, there will be no white space when you zoom and pan.
If your image does not fit or scale properly, there will be white space on the sides OR the top.
First make sure your image is the correct size. Next you need to add minimumZoomScale and maximumZoomScale to the scrollView. The rest will work after that. You can use auto-layout or frames. Up to you.
This example uses auto-layout:
#import "ViewController.h"
#interface AutoLayoutScrollView : UIScrollView
#property (nonatomic, weak) UIView *contentView;
#end
#implementation AutoLayoutScrollView
- (instancetype)init {
if (self = [super init]) {
UIView *view = [[UIView alloc] init];
self.contentView = view;
[self addSubview:view];
[self.contentView.leftAnchor constraintEqualToAnchor:self.leftAnchor].active = YES;
[self.contentView.rightAnchor constraintEqualToAnchor:self.rightAnchor].active = YES;
[self.contentView.topAnchor constraintEqualToAnchor:self.topAnchor].active = YES;
[self.contentView.bottomAnchor constraintEqualToAnchor:self.bottomAnchor].active = YES;
[self.contentView setTranslatesAutoresizingMaskIntoConstraints:NO];
}
return self;
}
- (void)didMoveToSuperview {
[super didMoveToSuperview];
UIView *parent = self.superview;
if (parent) {
[self.leftAnchor constraintEqualToAnchor:parent.leftAnchor].active = YES;
[self.rightAnchor constraintEqualToAnchor:parent.rightAnchor].active = YES;
[self.topAnchor constraintEqualToAnchor:parent.topAnchor].active = YES;
[self.bottomAnchor constraintEqualToAnchor:parent.bottomAnchor].active = YES;
[self setTranslatesAutoresizingMaskIntoConstraints:NO];
}
}
#end
#interface ViewController () <UIScrollViewDelegate>
#property (nonatomic, strong) AutoLayoutScrollView *scrollView;
#property (nonatomic, strong) UIImageView *imageView;
#property (nonatomic, strong) UIPanGestureRecognizer *panGesture;
#end
#implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.scrollView = [[AutoLayoutScrollView alloc] init];
[self.view addSubview:self.scrollView];
[self.scrollView.contentView.widthAnchor constraintEqualToAnchor:self.view.widthAnchor].active = YES;
[self.scrollView.contentView.heightAnchor constraintEqualToAnchor:self.view.heightAnchor].active = YES;
self.imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"Image"]];
[self.imageView setContentMode:UIViewContentModeScaleAspectFit];
[self.scrollView.contentView addSubview:self.imageView];
[self.imageView.leftAnchor constraintEqualToAnchor:self.scrollView.contentView.leftAnchor].active = YES;
[self.imageView.rightAnchor constraintEqualToAnchor:self.scrollView.contentView.rightAnchor].active = YES;
[self.imageView.topAnchor constraintEqualToAnchor:self.scrollView.contentView.topAnchor].active = YES;
[self.imageView.bottomAnchor constraintEqualToAnchor:self.scrollView.contentView.bottomAnchor].active = YES;
[self.imageView setTranslatesAutoresizingMaskIntoConstraints:NO];
[self.scrollView setMinimumZoomScale:1.0];
[self.scrollView setMaximumZoomScale:3.0];
[self.scrollView setZoomScale:1.0f animated:YES];
[self.scrollView setDelegate:self];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {
return self.imageView;
}
#end
My ViewController looks like this when initially loaded:
When show button is tapped it must change like this:
my code is:
- (IBAction)show:(id)sender {
[self change];
[tableView reloadData];
}
- (IBAction)close:(id)sender {
[self change];
[tableView reloadData];
}
-(void)change{
//assigning initial bounds to frame-1
CGRect frame1=CGRectMake(0, _pastProcessTV.frame.origin.y, self.view.bounds.size.width, self.pastProcessTV.bounds.size.height);
//assigning new bounds to frame-2
CGRect frame2=CGRectMake(0, **CGFloat y**,self.view.bounds.size.width,***CGFloat height***);
if (_showFullButton.isTouchInside) {
tableView.frame = frame2;
}
else{
tableview.frame = frame1;
}
}
I tried different ways. it is not working.can anyone help me in giving Y-coordinate and width
As you are using autolayout you have to take outlet of topconstraint of the tableview and when you want to expand it set its value to 0
So it will work as expected
if you are using iOS 7
[self.view layoutIfNeeded] is compulsary
If you have to use auto layout, please try like this picture
Make Layout Constraint Property
And try this code
#import "ViewController.h"
#interface ViewController ()
{
CGFloat oldtableViewTopValue;
}
#property (weak, nonatomic) IBOutlet NSLayoutConstraint *tableViewTopLC;
#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.
}
- (void) viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
[self.view setNeedsLayout];
[self.view layoutIfNeeded];
oldtableViewTopValue = _tableViewTopLC.constant;
}
- (IBAction)showBtnAction:(id)sender
{
[UIView animateWithDuration:0.5f animations:^{
_tableViewTopLC.constant = (_tableViewTopLC.constant==oldtableViewTopValue ? 0 : oldtableViewTopValue);
[self.view setNeedsLayout];
[self.view layoutIfNeeded];
}];
}
#end
Please turn off autolayout from Storyboard
I have a view with a property that should take an NSString from my view controller and display an image. If I hard code locationImageFile with "320x213-1.png" in my view, the image displays properly, but if I try to set locationImageFile from my view controller, the image doesn't appear. I feel like I'm missing something pretty basic. Side note: I seem to be able to set the locationTitle property from my view controller without any problems.
LocationViewController.m
#import "LocationViewController.h"
#import "LocationView.h"
#implementation LocationViewController
{
LocationView *_locationView;
}
- (void)loadView
{
CGRect frame = [[UIScreen mainScreen] bounds];
_locationView = [[LocationView alloc] initWithFrame:frame];
[self setView:_locationView];
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.
_locationView.locationTitle.text = aLocation.name;
_locationView.locationImageFile = #"320x213-1.png";
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#end
LocationView.m
#import "LocationView.h"
#implementation LocationView
#synthesize locationTitle;
#synthesize locationImageFile;
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
[self setBackgroundColor: [UIColor blueColor]];
// Image container
UIImage *locationImage = [UIImage imageNamed:locationImageFile];
UIImageView *locationImageContainer = [[UIImageView alloc] initWithImage:locationImage];
[locationImageContainer setTranslatesAutoresizingMaskIntoConstraints:NO];
locationImageContainer.backgroundColor = [UIColor yellowColor];
[self addSubview:locationImageContainer];
// Text line
locationTitle = [[UILabel alloc]init];
[locationTitle setTranslatesAutoresizingMaskIntoConstraints:NO];
locationTitle.backgroundColor = [UIColor whiteColor];
[self addSubview:locationTitle];
}
return self;
}
#end
I think this is because the loadView method are invoke earlier than viewDidLoad method.
so when you set _locationView.locationImageFile = #"320x213-1.png";,the containerView's image are not being set.
You can consider declare locationImageContainer as a property of locationView , and set it's image directly.like
_locationView.locationImageContainer.image = [UIImage imageNamed:#"320x213-1.png"];
instead of setting locationImageFile as a property.
When LocationView is initialized, the value of the instance variable locationImageFile equals nil. Override the setter of the locationImageFile property inside LocationView.m like this:
- (void)setLocationImageFile:(NSString *)aLocationImageFile
{
locationImageFile = aLocationImageFile;
locationImageContainer.image = [UIImage imageNamed:aLocationImageFile];
}
You can try, doing it like this:
_locationView.locationImageFile = [UIImage imageNamed:locationImageFile];
if you did it like this:
_locationView.locationImageFile = locationImageFile;
I am following Apress Beginning IOS 6 for school where we were asked by the professor to implement a custom algorithm that switches between 3 views (blue, yellow, and green) with each press of the "Next View" button in the toolbar. My approach was to add the subviews at different indices and shuffle the views in the hierarchy in BIDSwitchViewController.m:
#import "BIDSwitchViewController.h"
#import "BIDYellowViewController.h"
#import "BIDBlueViewController.h"
#import "BIDGreenViewController.h"
NSInteger count;
#interface BIDSwitchViewController ()
#end
#implementation BIDSwitchViewController
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
self.yellowViewController = [[BIDYellowViewController alloc] initWithNibName:#"YellowView"
bundle:nil];
self.greenViewController = [[BIDGreenViewController alloc] initWithNibName:#"GreenView"
bundle:nil];
self.blueViewController = [[BIDBlueViewController alloc] initWithNibName:#"BlueView"
bundle:nil];
//the topmost view is the last one in the stack (2)
[self.view insertSubview:self.blueViewController.view atIndex:2];
[self.view insertSubview:self.yellowViewController.view atIndex:1];
[self.view insertSubview:self.greenViewController.view atIndex:0];
[self.view setBackgroundColor:self.blueViewController.view.backgroundColor];
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.
self.blueViewController = [[BIDBlueViewController alloc]
initWithNibName:#"BlueView" bundle:nil];
[self.view insertSubview:self.blueViewController.view atIndex:0];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.;
self.blueViewController = nil;
self.yellowViewController = nil;
self.greenViewController = nil;
}
- (IBAction)switchViews:(id)sender
{
[UIView beginAnimations:#"View Flip" context:nil];
[UIView setAnimationDuration:1.0];
[UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
[UIView setAnimationTransition:
UIViewAnimationTransitionFlipFromRight
forView:self.view cache:YES];
switch (count)
{
case 0:
[self.view sendSubviewToBack:self.blueViewController.view];
[self.view bringSubviewToFront:self.yellowViewController.view];
[self.view setBackgroundColor:self.yellowViewController.view.backgroundColor];
break;
case 1:
[self.view sendSubviewToBack:self.yellowViewController.view];
[self.view bringSubviewToFront:self.greenViewController.view];
[self.view setBackgroundColor:self.greenViewController.view.backgroundColor];
break;
case 2:
[self.view sendSubviewToBack:self.greenViewController.view];
[self.view bringSubviewToFront:self.blueViewController.view];
[self.view setBackgroundColor:self.blueViewController.view.backgroundColor];
break;
}
if (++count >= 3)
{
count = 0;
}
[UIView commitAnimations];
}
#end
Here is the code in BIDAppDelegate.m where the root view controller is added as an instance of BIDSwitchViewController:
#implementation BIDAppDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
self.switchViewController = [[BIDSwitchViewController alloc]
initWithNibName:#"SwitchView" bundle:nil];
UIView *switchView = self.switchViewController.view;
CGRect switchViewFrame = switchView.frame;
switchViewFrame.origin.y += [UIApplication
sharedApplication].statusBarFrame.size.height;
switchView.frame = switchViewFrame;
//[self.window addSubview:switchView];
self.window.rootViewController = self.switchViewController;
self.window.backgroundColor = [UIColor whiteColor];
[self.window makeKeyAndVisible];
return YES;
}
And the BIDSwitchViewController.h header file:
#import <UIKit/UIKit.h>
#class BIDSwitchViewController;
#interface BIDAppDelegate : UIResponder <UIApplicationDelegate>
#property (strong, nonatomic) UIWindow *window;
#property (strong, nonatomic) BIDSwitchViewController *switchViewController;
#end
The app and logic all work as the views switch from blue -> yellow -> green and back to blue again. As shown in the first picture (BIDBlueViewController's BlueView.xib subview of the BIDSubViewController) each of the views overlap the toolbar slightly. I have double and triple checked all of my simulated metrics in IB with the help of one of my classmates:
Am I using poor practice in shuffling the topmost views through the view hierarchy array, instead of removing each view via the book's method of "removeFromParentViewController()," or is their another, hidden cause for the sub views not properly sitting inside / behind the parent view?
Your UIToolbar control's Z-Order on it's view is behind your blue view controller. Since you created it in IB, you can add an IBOutlet for it, and bring it's view to top of the parent view. You're loading the ViewControllers as subviews, so they are all subviews of self.view of your parent.
In your header definition:
IBOutlet *toolBar UIToolbar;
Bring to front in your implementation.
[self.view bringSubviewToFront:toolBar];
You can do this after you've added the blue controller subview or at the end of all your case statements.