UIPickerView Maximum Width in iOS 9 - ios

I have an app that uses a UIPickerView to set various parameters having to do with line style for a graph series (line width, colour, and line style). This picker is used in a table view row. I have defined the frame for the picker so that its width fills the width of the cell's contentView member. Up until iOS 9, this appeared to work. With iOS 9, there appears to be some sort of maximum cap on the width of a UIPickerView. Has anyone encountered anything similar to this?
The picker view is being created like this:
self.picker = [[[UIPickerView alloc] init] autorelease];
[self.contentView addSubview:self.picker];
self.picker.dataSource = self;
self.picker.delegate = self;
self.picker.backgroundColor = [UIColor grouped_table_view_background_colour];
The cell is layed out as follows:
-(void) layoutSubviews
{
// we need to allow the base class to perform its layout.
static CGFloat left_margin = 40;
static CGFloat right_margin = 40;
CGSize my_size;
[super layoutSubviews];
my_size = self.contentView.bounds.size;
my_size.width -= left_margin + right_margin;
// we now need to lay out the views.
CGRect picker_rect = CGRectMake(left_margin, 5, my_size.width, my_size.height);
self.picker.frame = picker_rect;
// we want to look at the bounds of the picker
CGRect picker_bounds = self.picker.bounds;
NSLog(#"picker bounds x=%g, y=%g, w=%g, h=%g", picker_bounds.origin.x, picker_bounds.origin.y, picker_bounds.size.width, picker_bounds.size.height);
}
I am also overloading the widthForComponent method as follows:
-(CGFloat) pickerView:(UIPickerView *)pickerView widthForComponent:(NSInteger)component
{
// we want to look at the bounds of the picker
CGRect picker_bounds = self.picker.bounds;
NSLog(#"picker bounds x=%g, y=%g, w=%g, h=%g", picker_bounds.origin.x, picker_bounds.origin.y, picker_bounds.size.width, picker_bounds.size.height);
return picker_bounds.size.width / 3;
}
I can see that the bounds of the view appear correctly both in the values that are logged as well as the background colour of the view. Despite this, the picker appears to fill less than half the width that is available (688 points on my iPad)

After [[UIPickerView alloc] init] the Picker has a size of {320,216} and this size will be used in pickerView:widthForComponent:. If you just resize the picker afterwards, the function pickerView:widthForComponent: won't be called again, so the components are stuck at their width.
Try to initialise the picker with the correct size like..
picker=[[UIDatePicker new] initWithFrame:CGRectMake(0.0, 0.0, CGRectGetWidth(self.view.bounds), 216.0)];
or call [self.picker setNeedsLayout] after you change the picker frame to force pickerView:widthForComponent: to be called again.

Related

Can't tap UICollectionView item

I'm building an app whereas I've got a UICollectionView with a custom layout. I have a problem whereas I cannot tap some rows. Here's an overview over what happens
1) App starts and presents a UICollectionView
2) 3 test items are displayed, using the visual debugger in Xcode, you can see that there is something not right with the hierarchy
The red row can't be tapped now, but the yellow and green rows can.
3) User taps the yellow item, and segues to another page
4) User pops the shown UIViewController and returns to the UICollectionView whereas the viewWillAppear method reloads the UICollectionView like so:
[self.collectionView reloadData];
5) Re-entering the visual debugger shows that the hierarchy seems shifted, and the yellow row is now untappable, but the red and green rows can be tapped.
What could be the reason for this? I'll post any relevant code, ask for what parts you'd like to see.
Update
The UIViewController displaying the UICollectionView
- (UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
ShareViewCell *view = [collectionView dequeueReusableCellWithReuseIdentifier:#"share" forIndexPath:indexPath];
view.share = [self.sharesController shareAtIndex:indexPath.item];
return view;
}
Custom cell:
- (instancetype)initWithFrame:(CGRect)frame
{
if (self = [super initWithFrame:frame]) {
self.leftBorderView = [UIView new];
[self.contentView addSubview:self.leftBorderView];
self.label = [UILabel new];
self.label.font = [UIFont boldSystemFontOfSize:10];
self.label.numberOfLines = 0;
self.label.lineBreakMode = NSLineBreakByWordWrapping;
[self.contentView addSubview:self.label];
}
return self;
}
- (void)layoutSubviews
{
[super layoutSubviews];
self.leftBorderView.frame = CGRectMake(0, 0, 1.5, self.bounds.size.height);
CGSize labelSize = [self.label sizeThatFits:CGSizeMake(self.bounds.size.width - 10.0f, MAXFLOAT)];
NSTimeInterval durationOfShare = [self.share.endSpan timeIntervalSinceDate:self.share.startSpan] / 3600;
CGFloat middleOfCell = self.bounds.size.height / 2;
CGFloat yPositionToUse = middleOfCell - (labelSize.height / 2);
if (durationOfShare < 0.25)
{
[self.label setHidden:YES];// to small to be shown
} else if (durationOfShare > 0.5)
{
yPositionToUse = 8; // show it at the top
}
self.label.frame = CGRectMake(8, yPositionToUse, labelSize.width, labelSize.height);
}
Update 2
Is the UICollectionReusableView blocking tap of the UICollectionViewCell?
Ok,
First, you should be more precise in your question : you're using some code found on some question on StackOverflow.
The code seems to be this Calendar UI made with UICollectionView.
This is a sample code, quickly built for the sake of a StackOverflow answer (with a bounty). It's not finished, has no contributors, and you should try to read it and improve over it !
From your debugger's captures, it seems you have some view which overlays on top of your collectionView's cells.
From reading this code, I see it uses some supplementary view to present 'hour' blocks. This supplementary view class is HourReusableView. And it's the view coming on top on your debugger's captures
CalendarViewLayout is responsible to compute these supplementary views frame, as it does for colored event blocks (see method - (void)prepareLayout)
I might bet that these supplementary views's Z-order isn't predictable - all views have a default zIndex of 0. One way to fix it ? After line 67 of this file, set a negative zIndex on the UICollectionViewLayoutAttributes of the hour block. This way, you make sure hour supplementary views are always behind your cells, and don't intercept the cell's touch

iOS: Autolayout causing UIScrollView to not scroll

I have set up a UIScrollView with which I want to display 12 images (only 8 fit on screen) laid out horizontally. In the following image you can see the problem I'm having (which makes my scroll view not scroll), my constraints and the UIScrollView which I have added on storyboard:
I have called the following method on -(void)viewDidLoad, where I "set up"my scrollview (itemList is my scroll view property and itemNames a array with the images'names):
- (void)setupHorizontalScrollView
{
self.itemList.delegate = self;
[self.itemList setTranslatesAutoresizingMaskIntoConstraints:NO];
[self.itemList setBackgroundColor:[UIColor blackColor]];
[self.itemList setCanCancelContentTouches:NO];
self.itemList.indicatorStyle = UIScrollViewIndicatorStyleWhite;
self.itemList.clipsToBounds = NO;
self.itemList.scrollEnabled = YES;
self.itemList.pagingEnabled = NO;
NSInteger tot=0;
CGFloat cx = 0;
for (; ; tot++) {
if (tot==12) {
break;
}
UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:[self.itemNames objectAtIndex:tot]]];
CGRect rect = imageView.frame;
rect.size.height = 40;
rect.size.width = 40;
rect.origin.x = cx;
rect.origin.y = 0;
imageView.frame = rect;
[self.itemList addSubview:imageView];
cx += imageView.frame.size.width;
}
[self.itemList setContentSize:CGSizeMake(cx, [self.itemList bounds].size.height)];
}
I have added the [self.itemList setTranslatesAutoresizingMaskIntoConstraints:NO]; because I saw this suggestion on other posts, but it doesn't work with or without it. The only way it works is if I uncheck use AutoLayout on the storyboard, but that moves the UIImageViewI use to look as a navigation bar to the bottom of the screen.
I don't know what to do anymore, any help is appreciated :)
Try to set your scrollView's Content size int "viewDidLayoutSubviews" method with keeping the autolayouts set.
-(void)viewDidLayoutSubviews
{
[self.itemList setContentSize:CGSizeMake(required_width, required_height)];
}
Two Solutions:
Create different constraints that can be satisfied simultaneously (you will have to edit). I think the problem is your bottom space and top space constraints are mutually exclusive. please remove one and try again. IF this is difficult for you, try adding another UIView to contain the UIScrollView to help manage your constraints, it might seem odd at first, but sometimes adding another view to contain your view actually makes it simpler at each level.
Turn off Autolayout, and change the autoresize masks of your UIImageView to be what you wish.
Insert: [scrollView setContentSize:CGSizeMake(x,y)]; in the following method:
-(void)viewWillAppear:(BOOL)animated

Centering and sizeToFit subview at run time and during orientation changes

The is the first of several problems I'm having setting up some UIViews and subviews. I have a UIView that is dynamically positioned on screen at run time. That UIView (master) contains another UIView (child) which wraps a UIImageView and a UILabel. Here are the requirements I have for this arrangement:
The child UIView must stay centered in the master UIView when the device rotates.
The text in the UILabel can be very long or very short and the child UIView with the image and text must still remain centered.
I would like to avoid subclassing UIView to handle this scenario and I would also like to avoid any frame/positioning code in willRotateToInterfaceOrientation. I'd like to handle all of this with some autoresizingMask settings in I.B. and maybe a little forced resizing code, if possible.
This is the arrangement of controls in Interface Builder(highlighted in red):
With Interface Builder, the autoresizingMask properties have been set like so, for the described controls
UIView (master): Flexible top margin, Flexible left margin, Flexible right margin, Flexible width
UIView (child): Flexible top margin, Flexible bottom margin, Flexible left margin, Flexible right margin, Flexible width, Flexible height. (All modes, except None)
UIImageView: Flexible right margin
UILabel: Flexible right margin
This is the view (red bar with image and text) after it's been added programmatically at run time while in portrait mode:
The master UIView's background is a light-red colored image. The child UIView's background is slightly darker than that, and the UILabel's background is even darker. I colored them so that I could see their bounds as the app responded to rotation.
It's clear to me that:
It is not centered but ...
After changing the text from it's default value in I.B from "There is no data in this map extent." to "TEST1, 123." the label contracts correctly.
This is the view after it's been added while in portrait and then rotated to landscape mode:
From here I can see that:
It is still not centered and perhaps at its original frame origin prior to rotation
The UIView (child) has expanded to fill more of the screen when it shouldn't.
The UIView (master) has properly expanded to fill the screen width.
This is the code that got me where I am now. I call the method showNoDataStatusView from viewDidLoad:
// Assuming
#define kStatusViewHeight 20
- (void)showNoDataStatusView {
if (!self.noDataStatusView.superview) {
self.noDataStatusView.frame = CGRectMake(self.mapView.frame.origin.x,
self.mapView.frame.origin.y,
self.mapView.frame.size.width,
kStatusViewHeight);
self.noDataStatusView.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:#"bgRedStatus.png"]];
// Position the label view in the center
self.noDataStatusLabelView.center = CGPointMake(self.noDataStatusView.frame.size.width/2,
self.noDataStatusView.frame.size.height/2);
// Test different text
self.noDataStatusLabel.text = #"Testing, 123.";
// Size to fit label
[self.noDataStatusLabel sizeToFit];
// Test the status label view resizing
[self.noDataStatusLabelView resizeToFitSubviews];
// Add view as subview
[self.view addSubview:self.noDataStatusView];
}
}
Please note the following:
resizeToFitSubviews is a category I placed on UIView once I found that UIView's won't automatically resize to fit their subviews even when you call sizeToFit. This question, and this question explained the issue. See the code for the category, below.
I have thought about creating a UIView subclass that handles all this logic for me, but it seems like overkill. It should be simple to arrange this in I.B. right?
I have tried setting every resizing mask setting in the book, as well as adjusting the order in which the resizing of the label and view occur as well as the point at which the master view is added as a subview. Nothing seems to be working as I get odd results every time.
UIView resizeToFitSubviews category implementation method:
-(void)resizeToFitSubviews
{
float width = 0;
float height = 0;
// Loop through subviews to determine max height/width
for (UIView *v in [self subviews]) {
float fw = v.frame.origin.x + v.frame.size.width;
float fh = v.frame.origin.y + v.frame.size.height;
width = MAX(fw, width);
height = MAX(fh, height);
}
[self setFrame:CGRectMake(self.frame.origin.x, self.frame.origin.y, width, height)];
}
What I want to know is why the UIView (child) is not properly centered after it's superview is added to the view hierarchy. It looks as though its got the proper width, but is somehow retaining the frame it had in I.B. when the label read "There is no data in this map extent."
I want to also know why it's not centered after device rotation and whether or not the approach I'm taking here is wise. Perhaps this is causing the other issues I'm having. Any UIView layout help here would be greatly appreciated.
Thanks!
If you are able to target iOS 6 you could use the new Auto Layout functionality to make this much much easier to manage - I've been reading a great tutorial by Ray Wenderlich that seems to be perfect to solve the problem you are seeing.
The problem here is that my UIView (master) does not layout it's subviews automatically when the device rotates and the "springs & struts" layout method used to position the image and interior UIView was inefficient. I solved the problem by doing two things.
I got rid of the internal UIView (child) instance, leaving only the UIView (master) and inside of that a UILabel and UIImageView.
I then created a UIView subclass called StatusView and in it I implement the layoutSubviews method. In its constructor I add a UIImageView and UILabel and position them dynamically. The UILabel is positioned first based on the size of the text and then the UIImageView is placed just to the left of it and vertically centered. That's it. In layoutSubviews I ensure that the positions of the elements are adjusted for the new frame.
Additionally, since I need to swap the background, message and possibly the image in some circumstances, it made sense to go with a custom class. There may be memory issues here/there but I'll iron them out when I run through this with the profiling tool.
Finally, I'm not totally certain if this code is rock solid but it does work. I don't know if I need the layout code in my init method, either. Layout subviews seems to be called shortly after the view is added as a subview.
Here's my class header:
#import <UIKit/UIKit.h>
typedef enum {
StatusViewRecordCountType = 0,
StatusViewReachedMaxRecordCountType = 1,
StatusViewZoomInType = 2,
StatusViewConnectionLostType = 3,
StatusViewConnectionFoundType = 4,
StatusViewNoDataFoundType = 5,
StatusViewGeographyIntersectionsType = 6,
StatusViewRetreivingRecordsType = 7
} StatusViewType;
#interface StatusView : UIView
#property (strong, nonatomic) NSString *statusMessage;
#property (nonatomic) StatusViewType statusViewType;
- (id)initWithFrame:(CGRect)frame message:(NSString*)message type:(StatusViewType)type;
#end
... and implementation:
#import "StatusView.h"
#define kConstrainSizeWidthOffset 10
#define kImageBufferWidth 15
#interface StatusView ()
#property (nonatomic, strong) UILabel *statusMessageLabel;
#property (nonatomic, strong) UIFont *statusMessageFont;
#property (nonatomic, strong) UIImage *statusImage;
#property (nonatomic, strong) UIImageView *statusImageView;
#end
#implementation StatusView
#synthesize statusMessageLabel = _statusMessageLabel;
#synthesize statusMessageFont = _statusMessageFont;
#synthesize statusImageView = _statusImageView;
#synthesize statusMessage = _statusMessage;
#synthesize statusViewType = _statusViewType;
#synthesize statusImage = _statusImage;
- (id)initWithFrame:(CGRect)frame message:(NSString *)message type:(StatusViewType)type {
self = [super initWithFrame:frame];
if (self) {
if (message != nil) {
_statusMessage = message;
_statusMessageFont = [UIFont fontWithName:#"Avenir-Roman" size:15.0];
CGSize constrainSize = CGSizeMake(self.frame.size.width - kImageBufferWidth - kConstrainSizeWidthOffset, self.frame.size.height);
// Find the size appropriate for this message
CGSize messageSize = [_statusMessage sizeWithFont:_statusMessageFont constrainedToSize:constrainSize];
// Create label and position at center of status view
CGRect labelFrame = CGRectMake(self.frame.origin.x,
self.frame.origin.y,
messageSize.width,
messageSize.height);
_statusMessageLabel = [[UILabel alloc] initWithFrame:labelFrame];
_statusMessageLabel.backgroundColor = [UIColor clearColor];
_statusMessageLabel.textColor = [UIColor whiteColor];
_statusMessageLabel.font = _statusMessageFont;
// Set shadow and color
_statusMessageLabel.shadowOffset = CGSizeMake(0, 1);
_statusMessageLabel.shadowColor = [UIColor blackColor];
// Center the label
CGPoint centerPoint = CGPointMake(self.frame.size.width / 2, self.frame.size.height / 2);
_statusMessageLabel.center = centerPoint;
// Gets rid of fuzziness
_statusMessageLabel.frame = CGRectIntegral(_statusMessageLabel.frame);
// Flex both the width and height as well as left and right margins
_statusMessageLabel.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin;
// Set label text
_statusMessageLabel.text = _statusMessage;
[self addSubview:_statusMessageLabel];
}
self.statusViewType = type;
if (_statusImage != nil) {
// Create image view
_statusImageView = [[UIImageView alloc] initWithImage:_statusImage];
// Vertically center the image
CGPoint centerPoint = CGPointMake(_statusMessageLabel.frame.origin.x - kImageBufferWidth,
self.frame.size.height / 2);
_statusImageView.center = centerPoint;
[self addSubview:_statusImageView];
}
}
return self;
}
- (void)layoutSubviews {
CGSize constrainSize = CGSizeMake(self.frame.size.width - kImageBufferWidth - kConstrainSizeWidthOffset, self.frame.size.height);
// Find the size appropriate for this message
CGSize messageSize = [_statusMessage sizeWithFont:_statusMessageFont constrainedToSize:constrainSize];
// Create label and position at center of status view
CGRect labelFrame = CGRectMake(self.frame.origin.x,
self.frame.origin.y,
messageSize.width,
messageSize.height);
_statusMessageLabel.frame = labelFrame;
// Center the label
CGPoint centerPoint = CGPointMake(self.frame.size.width / 2, self.frame.size.height / 2);
_statusMessageLabel.center = centerPoint;
// Gets rid of fuzziness
_statusMessageLabel.frame = CGRectIntegral(_statusMessageLabel.frame);
if (_statusImageView != nil) {
// Vertically center the image
CGPoint centerPoint = CGPointMake(_statusMessageLabel.frame.origin.x - kImageBufferWidth,
self.frame.size.height / 2);
_statusImageView.center = centerPoint;
}
}
#pragma mark - Custom setters
- (void)setStatusMessage:(NSString *)message {
if (_statusMessage == message) return;
_statusMessage = message;
_statusMessageLabel.text = _statusMessage;
// Force layout of subviews
[self setNeedsLayout];
[self layoutIfNeeded];
}
- (void)setStatusViewType:(StatusViewType)statusViewType {
_statusViewType = statusViewType;
UIColor *bgColor = nil;
switch (_statusViewType) {
// Changes background and image based on type
}
self.backgroundColor = bgColor;
if (_statusImageView != nil) {
_statusImageView.image = _statusImage;
}
}
#end
Then in my view controller I can do this:
CGRect statusFrame = CGRectMake(self.mapView.frame.origin.x,
self.mapView.frame.origin.y,
self.mapView.frame.size.width,
kStatusViewHeight);
self.staticStatusView = [[StatusView alloc] initWithFrame:statusFrame message:#"600 records found :)" type:StatusViewRecordCountType];
self.staticStatusView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin;
[self.view addSubview:self.staticStatusView];
... and later on I can change it up by doing this:
self.staticStatusView.statusMessage = #"No data was found here";
self.staticStatusView.statusViewType = StatusViewNoDataFoundType;
Now I've got a reusable class rather than 12 UIView instances floating around my NIB with various settings and properties.

multiple UIPickerViews - without a .xib

I have a view. I would like to be able to put 1-3 UIPickerViews in it. The number of UIPickerViews is determined by the value of a variable myVariable. Each UIPickerView is different. Some of the values for myVariable mean that there will only be one UIPickerView in the view, but some mean that I will have to put 2 or 3 in the view, and it will be laid out vertically (so one UIPickerView is directly above the other). Right now, every case where myVariable means that it needs only 1 UIPickerView, I'm putting them in the view like this:
if (myVariable == kNeedsOnlyOnePicker)
{
myPicker = [[UIPickerView alloc] initWithFrame:self.view.frame];
[myPicker setDelegate:self];
[myPicker setDataSource:self];
myPicker.showsSelectionIndicator = YES;
[self.view addSubview:myPicker];
}
However, I'm just not sure how to tell the code something like this:
if (myVariable == kNeedsTwoPickers)
{
// put myPicker and myOtherPicker in self.view,
// and put myPicker above myOtherPicker.
}
I have a hunch I won't be able to use the .xib to do something like this, because I won't be able to set up different layouts (e.g. picker 1 above picker 2, picker 2 above picker 3, only picker 3).
TL;DR how do I programmatically say, "this subview will go above this other subview" or "this picker will go above this other picker"?
Specific methods/examples and/or general ideas would be great.
Thanks!
I found that I could set the frame for the subview and calculate its coordinates.
- (void)layout
{
for (int i= 0; i < [self.view.subviews count]; i++)
{
// calculate x, y, width, and height
UIView *subview = [self.view.subviews objectAtIndex:i];
subview.frame = CGRectMake(x, y, width, height);
}
}

How to change UIPickerView height

Is it possible to change the height of UIPickerView? Some applications seem to have shorter PickerViews but setting a smaller frame doesn't seem to work and the frame is locked in Interface Builder.
It seems obvious that Apple doesn't particularly invite mucking with the default height of the UIPickerView, but I have found that you can achieve a change in the height of the view by taking complete control and passing a desired frame size at creation time, e.g:
smallerPicker = [[UIPickerView alloc] initWithFrame:CGRectMake(0.0, 0.0, 320.0, 120.0)];
You will discover that at various heights and widths, there are visual glitches. Obviously, these glitches would either need to be worked around somehow, or choose another size that doesn't exhibit them.
None of the above approaches work in iOS 4.0
The pickerView's height is no longer re-sizable. There is a message which gets dumped to console if you attempt to change the frame of a picker in 4.0:
-[UIPickerView setFrame:]: invalid height value 66.0 pinned to 162.0
I ended up doing something quite radical to get the effect of a smaller picker which works in both OS 3.xx and OS 4.0. I left the picker to be whatever size the SDK decides it should be and instead made a cut-through transparent window on my background image through which the picker becomes visible. Then simply placed the picker behind (Z Order wise) my background UIImageView so that only a part of the picker is visible which is dictated by the transparent window in my background.
There are only three valid heights for UIPickerView (162.0, 180.0 and 216.0).
You can use the CGAffineTransformMakeTranslation and CGAffineTransformMakeScale functions to properly fit the picker to your convenience.
Example:
CGAffineTransform t0 = CGAffineTransformMakeTranslation (0, pickerview.bounds.size.height/2);
CGAffineTransform s0 = CGAffineTransformMakeScale (1.0, 0.5);
CGAffineTransform t1 = CGAffineTransformMakeTranslation (0, -pickerview.bounds.size.height/2);
pickerview.transform = CGAffineTransformConcat (t0, CGAffineTransformConcat(s0, t1));
The above code change the height of picker view to half and re-position it to the exact (Left-x1, Top-y1) position.
Try:
pickerview.transform = CGAffineTransformMakeScale(.5, 0.5);
In iOS 4.2 & 4.3 the following works:
UIDatePicker *datePicker = [[UIDatePicker alloc] init];
datePicker.frame = CGRectMake(0, 0, 320, 180);
[self addSubview:datePicker];
The following does not work:
UIDatePicker *datePicker = [[UIDatePicker alloc] initWithFrame:CGRectMake(0, 0, 320, 180)];
[self addSubview:datePicker];
I have an app that is in the app store with a 3 line date picker. I thought the height change may have been prevented because you see the text under the date picker's border, but this happens to the normal 216 height date picker too.
Which is the bug? Your guess is as good as mine.
Also there are 3 valid heights for UIDatePicker (and UIPickerView) 162.0, 180.0, and 216.0. If you set a UIPickerView height to anything else you will see the following in the console when debugging on an iOS device.
2011-09-14 10:06:56.180 DebugHarness[1717:707] -[UIPickerView setFrame:]: invalid height value 300.0 pinned to 216.0
As of iOS 9, you can freely change UIPickerView's width and height. No need to use the above mentioned transform hacks.
I have found that you can edit the size of the UIPickerView - just not with interface builder. open the .xib file with a text editor and set the size of the picker view to whatever you want. Interface builder does not reset the size and it seems to work. I'm sure apple locked the size for a reason so you'll have to experiment with different sizes to see what works.
Advantages:
Makes setFrame of UIPickerView behave like it should
No transform code within your UIViewController
Works within viewWillLayoutSubviews to rescale/position the UIPickerView
Works on the iPad without UIPopover
The superclass always receives a valid height
Works with iOS 5
Disadvantages:
Requires you to subclass UIPickerView
Requires the use of pickerView viewForRow to undo the transformation for the subViews
UIAnimations might not work
Solution:
Subclass UIPickerView and overwrite the two methods using the following code. It combines subclassing, fixed height and the transformation approach.
#define FIXED_PICKER_HEIGHT 216.0f
- (void) setFrame:(CGRect)frame
{
CGFloat targetHeight = frame.size.height;
CGFloat scaleFactor = targetHeight / FIXED_PICKER_HEIGHT;
frame.size.height = FIXED_PICKER_HEIGHT;//fake normal conditions for super
self.transform = CGAffineTransformIdentity;//fake normal conditions for super
[super setFrame:frame];
frame.size.height = targetHeight;
CGFloat dX=self.bounds.size.width/2, dY=self.bounds.size.height/2;
self.transform = CGAffineTransformTranslate(CGAffineTransformScale(CGAffineTransformMakeTranslation(-dX, -dY), 1, scaleFactor), dX, dY);
}
- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view
{
//Your code goes here
CGFloat inverseScaleFactor = FIXED_PICKER_HEIGHT/self.frame.size.height;
CGAffineTransform scale = CGAffineTransformMakeScale(1, inverseScaleFactor);
view.transform = scale;
return view;
}
An easy way to change the visible height of a picker view is to embed the picker in a UIView, adjust the parent view's height to the height you want to see of the picker, then enable "Clip Subviews" in Interface Builder on the parent UIView or set view.clipsToBounds = true in code.
I wasn't able to follow any of the above advice.
I watched multiple tutorials and found this one the most beneficial:
I added the following code to set the new height inside the "viewDidLoad" method, which worked in my app.
UIPickerView *picker = [[UIPickerView alloc] initWithFrame:CGRectMake(0.0, 0.0, 320.0, 120.0)];
[self.view addSubview:picker];
picker.delegate = self;
picker.dataSource = self;
Hope this was helpful!
This has changed a lot in iOS 9 (in iOS 8 it's pretty similar to what we're seeing here). If you can afford to target iOS 9 only, then you resize the UIPickerView as you see fit, by setting its frame. Good!
Here it is from iOS 9 Release Notes
UIPickerView and UIDatePicker are now resizable and
adaptive—previously, these views would enforce a default size even if
you attempted to resize them. These views also now default to a width
of 320 points on all devices, instead of to the device width on
iPhone.
Interfaces that rely on the old enforcement of the default size will
likely look wrong when compiled for iOS 9. Any problems encountered
can be resolved by fully constraining or sizing picker views to the
desired size instead of relying on implicit behavior.
I am working with ios 7, Xcode 5. I was able to adjust the height of date picker indirectly by enclosing it in a view. The container views height can be adjusted.
Create a view in IB or code. Add your picker as a subview of this view. Resize the view. This is easiest to do in IB. Create constraints from the view to its superview and from the picker to this new view.
Since the Picker curves around it spills out over the top and bottom of the view. You can see in IB when you add top and bottom constraints from the picker to the view it shows a standard space something like 16 points above and below the superview container. Set the view to clip it if you don't want this behaviour (ugly warning).
Here's what it looks like at 96 points high on an iPhone 5. The picker with the spillover is about 130 points high. Pretty skinny!
I'm using this in my project to prevent the picker from spreading out to an unnecessary height. This technique trims it down and forces a tighter spill over. It actually looks slicker to be a bit more compact.
Here's an image of the view showing the spillover.
Here's the IB constraints I added.
As mentioned above UIPickerView is now resizable. I just want to add though that if you want to change the pickerView's height in a tableView Cell, I didn't have any success with setting the height anchor to a constant. However, using lessThanOrEqualToConstant seems to work.
class PickerViewCell: UITableViewCell {
let pickerView = UIPickerView()
func setup() {
// call this from however you initialize your cell
self.contentView.addSubview(self.pickerView)
self.pickerView.translatesAutoresizingMaskIntoConstraints = false
let constraints: [NSLayoutConstraint] = [
// pin the pickerView to the contentView's layoutMarginsGuide
self.pickerView.leadingAnchor.constraint(equalTo: self.contentView.layoutMarginsGuide.leadingAnchor),
self.pickerView.topAnchor.constraint(equalTo: self.contentView.layoutMarginsGuide.topAnchor),
self.pickerView.trailingAnchor.constraint(equalTo: self.contentView.layoutMarginsGuide.trailingAnchor),
self.pickerView.bottomAnchor.constraint(equalTo: self.contentView.layoutMarginsGuide.bottomAnchor),
// set the height using lessThanOrEqualToConstant
self.pickerView.heightAnchor.constraint(lessThanOrEqualToConstant: 100)
]
NSLayoutConstraint.activate(constraints)
}
}
Even thought it is not resizing, another trick may help in the situation when the UIPicker is located at the bottom of the screen.
One can try moving it slightly downwards, but the central row should remain visible. This will help reveal some space above the picker since bottom rows will be offscreen.
I repeat that this is not the way of changing UIPicker view's height but some idea on what you can do if all other attempts fail.
Ok, after struggling for a long time with the stupid pickerview in iOS 4, I've decided to change my control into simple table:
here is the code:
ComboBoxView.m = which is actually looks more like pickerview.
//
// ComboBoxView.m
// iTrophy
//
// Created by Gal Blank on 8/18/10.
//
#import "ComboBoxView.h"
#import "AwardsStruct.h"
#implementation ComboBoxView
#synthesize displayedObjects;
#pragma mark -
#pragma mark Initialization
/*
- (id)initWithStyle:(UITableViewStyle)style {
// Override initWithStyle: if you create the controller programmatically and want to perform customization that is not appropriate for viewDidLoad.
if ((self = [super initWithStyle:style])) {
}
return self;
}
*/
#pragma mark -
#pragma mark View lifecycle
/*
- (void)viewDidLoad {
[super viewDidLoad];
// Uncomment the following line to display an Edit button in the navigation bar for this view controller.
// self.navigationItem.rightBarButtonItem = self.editButtonItem;
}
*/
/*
- (void)viewWillAppear:(BOOL)animated {
[super viewWillAppear:animated];
}
*/
/*
- (void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
}
*/
/*
- (void)viewWillDisappear:(BOOL)animated {
[super viewWillDisappear:animated];
}
*/
/*
- (void)viewDidDisappear:(BOOL)animated {
[super viewDidDisappear:animated];
}
*/
/*
// Override to allow orientations other than the default portrait orientation.
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
// Return YES for supported orientations
return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
*/
#pragma mark -
#pragma mark Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
// Return the number of sections.
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
// Return the number of rows in the section.
self.tableView.separatorStyle = UITableViewCellSeparatorStyleSingleLine;
return [[self displayedObjects] count];
}
// Customize the appearance of table view cells.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
NSString *MyIdentifier = [NSString stringWithFormat:#"MyIdentifier %i", indexPath.row];
UITableViewCell *cell = (UITableViewCell *)[tableView dequeueReusableCellWithIdentifier:MyIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:MyIdentifier] autorelease];
//cell.contentView.frame = CGRectMake(0, 0, 230.0,16);
UILabel *label = [[[UILabel alloc] initWithFrame:CGRectMake(0, 5, 230.0,19)] autorelease];
VivatAwardsStruct *vType = [displayedObjects objectAtIndex:indexPath.row];
NSString *section = [vType awardType];
label.tag = 1;
label.font = [UIFont systemFontOfSize:17.0];
label.text = section;
label.textAlignment = UITextAlignmentCenter;
label.baselineAdjustment = UIBaselineAdjustmentAlignCenters;
label.adjustsFontSizeToFitWidth=YES;
label.textColor = [UIColor blackColor];
//label.autoresizingMask = UIViewAutoresizingFlexibleHeight;
[cell.contentView addSubview:label];
//UIImage *image = nil;
label.backgroundColor = [UIColor whiteColor];
//image = [awards awardImage];
//image = [image imageScaledToSize:CGSizeMake(32.0, 32.0)];
//[cell setAccessoryType:UITableViewCellAccessoryDisclosureIndicator];
//UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
//cell.accessoryView = imageView;
//[imageView release];
}
return cell;
}
/*
// Override to support conditional editing of the table view.
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath {
// Return NO if you do not want the specified item to be editable.
return YES;
}
*/
/*
// Override to support editing the table view.
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {
if (editingStyle == UITableViewCellEditingStyleDelete) {
// Delete the row from the data source
[tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:YES];
}
else if (editingStyle == UITableViewCellEditingStyleInsert) {
// Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
}
}
*/
/*
// Override to support rearranging the table view.
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath {
}
*/
/*
// Override to support conditional rearranging of the table view.
- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath {
// Return NO if you do not want the item to be re-orderable.
return YES;
}
*/
#pragma mark -
#pragma mark Table view delegate
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
// Navigation logic may go here. Create and push another view controller.
/*
<#DetailViewController#> *detailViewController = [[<#DetailViewController#> alloc] initWithNibName:#"<#Nib name#>" bundle:nil];
// ...
// Pass the selected object to the new view controller.
[self.navigationController pushViewController:detailViewController animated:YES];
[detailViewController release];
*/
}
#pragma mark -
#pragma mark Memory management
- (void)didReceiveMemoryWarning {
// Releases the view if it doesn't have a superview.
[super didReceiveMemoryWarning];
// Relinquish ownership any cached data, images, etc that aren't in use.
}
- (void)viewDidUnload {
// Relinquish ownership of anything that can be recreated in viewDidLoad or on demand.
// For example: self.myOutlet = nil;
}
- (void)dealloc {
[super dealloc];
}
#end
Here is the .h file for that:
//
// ComboBoxView.h
// iTrophy
//
// Created by Gal Blank on 8/18/10.
//
#import <UIKit/UIKit.h>
#interface ComboBoxView : UITableViewController {
NSMutableArray *displayedObjects;
}
#property (nonatomic, retain) NSMutableArray *displayedObjects;
#end
now, in the ViewController where I had Apple UIPickerView I replaced with my own ComboBox view and made it size what ever I wish.
ComboBoxView *mypickerholder = [[ComboBoxView alloc] init];
[mypickerholder.view setFrame:CGRectMake(50, 220, 230, 80)];
[mypickerholder setDisplayedObjects:awardTypesArray];
that's it, now the only thing is left is to create a member variable in the combobox view that will hold current row selection, and we are good to go.
Enjoy everyone.
You can not generally do it in xib or setting frame programtically but if you open its parent xib as source and change height from there then it works.Right click the xib within which pickerview is contained,Search pickerview and you can find height,width etc in that tag,Change height there then save file.
<pickerView contentMode="scaleToFill" id="pai-pm-hjZ">
<rect key="frame" x="0.0" y="41" width="320" height="100"/>
<autoresizingMask key="autoresizingMask" widthSizable="YES" flexibleMaxY="YES"/>
<connections>
<outlet property="dataSource" destination="-1" id="Mo2-zp-Sl4"/>
<outlet property="delegate" destination="-1" id="nfW-lU-tsU"/>
</connections>
</pickerView>
As far as I know, it's impossible to shrink the UIPickerView. I also haven't actually seen a shorter one used anywhere. My guess is that it was a custom implementation if they did manage to shrink it.
If you want to create your picker in IB, you can post-resize it to a smaller size. Check to make sure it still draws correctly though, as there comes a point where it looks heinous.
Swift: You need to add a subview with clip to bounds
var DateView = UIView(frame: CGRectMake(0, 0, view.frame.width, 100))
DateView.layer.borderWidth=1
DateView.clipsToBounds = true
var myDatepicker = UIDatePicker(frame:CGRectMake(0,-20,view.frame.width,162));
DateView.addSubview(myDatepicker);
self.view.addSubview(DateView)
This should add a clipped 100 height date picker in the top of the view controller.
My trick: use datepicker's mask layer to make datePicker some part visible. as you see just like change the datepicke's frame.
- (void)timeSelect:(UIButton *)timeButton {
UIDatePicker *timePicker = [[UIDatePicker alloc] initWithFrame:CGRectMake(0, 0, kScreenWidth, 550)];
timePicker.backgroundColor = [UIColor whiteColor];
timePicker.layer.mask = [self maskLayerWithDatePicker:timePicker];
timePicker.layer.masksToBounds = YES;
timePicker.datePickerMode = UIDatePickerModeTime;
[self.view addSubview:timePicker];
}
- (CALayer *)maskLayerWithDatePicker:(UIDatePicker *)datePicker {
CAShapeLayer *shapeLayer = [[CAShapeLayer alloc] init];
UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(0, 0, datePicker.width*0.8, datePicker.height*0.8) cornerRadius:10];
shapeLayer.path = path.CGPath;
return shapeLayer;
}
I use a mask layer to change it's display size
// swift 3.x
let layer = CALayer()
layer.frame = CGRect(x: 0,y:0, width: displayWidth, height: displayHeight)
layer.backgroundColor = UIColor.red.cgColor
pickerView.layer.mask = layer
Embed in a stack view. Stack view is a component recently added by Apple in their iOS SDK to reflect grid based implementations in java script web based front end libraries such as bootstrap.
After a long day of scratching my head, I've found something that works for me. The codes below will recreate the UIDatePicker everytime the user change the phone orientation. This will remove whatever glitches that the UIDatePicker have after an orientation change.
Since we are recreating the UIDatePicker, we need an instance variable that will keep the selected date value. The codes below are tested on iOS 4.0.
#interface AdvanceDateViewController : UIViewController<UIPickerViewDelegate> {
UIDatePicker *datePicker;
NSDate *date;
}
#property (nonatomic, retain) UIDatePicker *datePicker;
#property (nonatomic, retain) NSDate *date;
-(void)resizeViewWithOrientation:(UIInterfaceOrientation) orientation;
#end
#implementation AdvanceDateViewController
#synthesize datePicker, date;
- (void)viewDidLoad {
[super viewDidLoad];
[self resizeViewWithOrientation:self.interfaceOrientation];
}
-(void)viewWillAppear:(BOOL)animated{
[super viewWillAppear:animated];
[self resizeViewWithOrientation:self.interfaceOrientation];
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
return YES;
}
-(void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration{
[super willRotateToInterfaceOrientation:toInterfaceOrientation duration:duration];
[self resizeViewWithOrientation:toInterfaceOrientation];
}
-(void)resizeViewWithOrientation:(UIInterfaceOrientation) orientation{
[self.datePicker removeFromSuperview];
[self.datePicker removeTarget:self action:#selector(refreshPickupDate) forControlEvents:UIControlEventValueChanged];
self.datePicker = nil;
//(Re)initialize the datepicker, thanks to Apple's buggy UIDatePicker implementation
UIDatePicker *dummyDatePicker = [[UIDatePicker alloc] init];
self.datePicker = dummyDatePicker;
[dummyDatePicker release];
[self.datePicker setDate:self.date animated:YES];
[self.datePicker addTarget:self action:#selector(refreshPickupDate) forControlEvents:UIControlEventValueChanged];
if(UIInterfaceOrientationIsLandscape(orientation)){
self.datePicker.frame = CGRectMake(0, 118, 480, 162);
} else {
self.datePicker.frame = CGRectMake(0, 200, 320, 216);
}
[self.view addSubview:self.datePicker];
[self.view setNeedsDisplay];
}
#end
stockPicker = [[UIPickerView alloc] init];
stockPicker.frame = CGRectMake(70.0,155, 180,100);
If You want to set the size of UiPickerView. Above code is surely gonna work for u.
In iOS 5.0, I got the following to work:
UIDatePicker *picker = [[UIDatePicker alloc] init];
picker.frame = CGRectMake(0.0, 0.0, 320.0, 160.0);
This created a date picker like the one Apple uses in the Calendar app when creating a new event in landscape mode. (3 rows high instead of 5.) This didn't work when I set the frame within the initWithFrame: method, but so far works when setting it using a separate method.
for iOS 5:
if you take a quick look at the UIPickerView Protocol Reference
you'll find
– pickerView:rowHeightForComponent:
– pickerView:widthForComponent:
I think is the first one you're looking for

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