UISlider with ProgressView combined - objective-c

Is there an apple-house-made way to get a UISlider with a ProgressView. This is used by many streaming applications e.g. native quicktimeplayer or youtube.
(Just to be sure: i'm only in the visualization interested)
cheers Simon

Here's a simple version of what you're describing.
It is "simple" in the sense that I didn't bother trying to add the shading and other subtleties. But it's easy to construct and you can tweak it to draw in a more subtle way if you like. For example, you could make your own image and use it as the slider's thumb.
This is actually a UISlider subclass lying on top of a UIView subclass (MyTherm) that draws the thermometer, plus two UILabels that draw the numbers.
The UISlider subclass eliminates the built-in track, so that the thermometer behind it shows through. But the UISlider's thumb (knob) is still draggable in the normal way, and you can set it to a custom image, get the Value Changed event when the user drags it, and so on. Here is the code for the UISlider subclass that eliminates its own track:
- (CGRect)trackRectForBounds:(CGRect)bounds {
CGRect result = [super trackRectForBounds:bounds];
result.size.height = 0;
return result;
}
The thermometer is an instance of a custom UIView subclass, MyTherm. I instantiated it in the nib and unchecked its Opaque and gave it a background color of Clear Color. It has a value property so it knows how much to fill the thermometer. Here's its drawRect: code:
- (void)drawRect:(CGRect)rect {
CGContextRef c = UIGraphicsGetCurrentContext();
[[UIColor whiteColor] set];
CGFloat ins = 2.0;
CGRect r = CGRectInset(self.bounds, ins, ins);
CGFloat radius = r.size.height / 2.0;
CGMutablePathRef path = CGPathCreateMutable();
CGPathMoveToPoint(path, NULL, CGRectGetMaxX(r) - radius, ins);
CGPathAddArc(path, NULL, radius+ins, radius+ins, radius, -M_PI/2.0, M_PI/2.0, true);
CGPathAddArc(path, NULL, CGRectGetMaxX(r) - radius, radius+ins, radius, M_PI/2.0, -M_PI/2.0, true);
CGPathCloseSubpath(path);
CGContextAddPath(c, path);
CGContextSetLineWidth(c, 2);
CGContextStrokePath(c);
CGContextAddPath(c, path);
CGContextClip(c);
CGContextFillRect(c, CGRectMake(r.origin.x, r.origin.y, r.size.width * self.value, r.size.height));
}
To change the thermometer value, change the MyTherm instance's value to a number between 0 and 1, and tell it to redraw itself with setNeedsDisplay.

This is doable using the standard controls.
In Interface Builder place your UISlider immediately on top of your UIProgressView and make them the same size.
On a UISlider the background horizontal line is called the track, the trick is to make it invisible. We do this with a transparent PNG and the UISlider methods setMinimumTrackImage:forState: and setMaximumTrackImage:forState:.
In the viewDidLoad method of your view controller add:
[self.slider setMinimumTrackImage:[UIImage imageNamed:#"transparent.png"] forState:UIControlStateNormal];
[self.slider setMaximumTrackImage:[UIImage imageNamed:#"transparent.png"] forState:UIControlStateNormal];
where self.slider refers to your UISlider.
I've tested the code in Xcode, and this will give you a slider with an independent progress bar.

Solution that suits my design:
class SliderBuffering:UISlider {
let bufferProgress = UIProgressView(progressViewStyle: .Default)
override init (frame : CGRect) {
super.init(frame : frame)
}
convenience init () {
self.init(frame:CGRect.zero)
setup()
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
setup()
}
func setup() {
self.minimumTrackTintColor = UIColor.clearColor()
self.maximumTrackTintColor = UIColor.clearColor()
bufferProgress.backgroundColor = UIColor.clearColor()
bufferProgress.userInteractionEnabled = false
bufferProgress.progress = 0.0
bufferProgress.progressTintColor = UIColor.lightGrayColor().colorWithAlphaComponent(0.5)
bufferProgress.trackTintColor = UIColor.blackColor().colorWithAlphaComponent(0.5)
self.addSubview(bufferProgress)
}
}

Create a UISlider:
// 1
// Make the slider as a public propriety so you can access it
playerSlider = [[UISlider alloc] init];
[playerSlider setContinuous:YES];
[playerSlider setHighlighted:YES];
// remove the slider filling default blue color
[playerSlider setMaximumTrackTintColor:[UIColor clearColor]];
[playerSlider setMinimumTrackTintColor:[UIColor clearColor]];
// Chose your frame
playerSlider.frame = CGRectMake(--- , -- , yourSliderWith , ----);
// 2
// create a UIView that u can access and make it the shadow of your slider
shadowSlider = [[UIView alloc] init];
shadowSlider.backgroundColor = [UIColor lightTextColor];
shadowSlider.frame = CGRectMake(playerSlider.frame.origin.x , playerSlider.frame.origin.y , playerSlider.frame.size.width , playerSlider.frame.origin.size.height);
shadowSlider.layer.cornerRadius = 4;
shadowSlider.layer.masksToBounds = YES;
[playerSlider addSubview:shadowSlider];
[playerSlider sendSubviewToBack:shadowSlider];
// 3
// Add a timer Update your slider and shadow slider programatically
[NSTimer scheduledTimerWithTimeInterval:1 target:self selector:#selector(updateSlider) userInfo:nil repeats:YES];
-(void)updateSlider {
// Update the slider about the music time
playerSlider.value = audioPlayer.currentTime; // based on ur case
playerSlider.maximumValue = audioPlayer.duration;
float smartWidth = 0.0;
smartWidth = (yourSliderFullWidth * audioPlayer.duration ) / 100;
shadowSlider.frame = CGRectMake( shadowSlider.frame.origin.x , shadowSlider.frame.origin.y , smartWidth , shadowSlider.frame.size.height);
}
Enjoy! P.S. I might have some typos.

Idea 1:
You could easily use the UISlider as a progress view by subclassing it. It responds to methods such as 'setValue:animated:' with which you can set the value (i.e: progress) of the view.
Your only 'restriction' creating what you see in your example is the buffer bar, which you could create by 'creatively' skinning the UISlider (because you can add custom skins to it), and perhaps set that skin programmatically.
Idea 2:
Another (easier) option is to subclass UIProgressView, and create a UISlider inside that subclass. You can skin the UISlider to have a see-through skin (no bar, just the knob visible) and lay it over the UIProgressView.
You can use the UIProgressView for the pre-loading (buffering) and the UISlider for movie control / progress indication.
Seems fairly easy :-)
Edit: to actually answer your question, there is no in-house way, but it would be easy to accomplish with the tools given.

You can do some trick like this, it's more easy and understanding. Just insert the code bellow in your UISlider subclass.
- (void)layoutSubviews
{
[super layoutSubviews];
if (_availableDurationImageView == nil) {
// step 1
// get max length that our "availableDurationImageView" will show
UIView *maxTrackView = [self.subviews objectAtIndex:self.subviews.count - 3];
UIImageView *maxTrackImageView = [maxTrackView.subviews objectAtIndex:0];
_maxLength = maxTrackImageView.width;
// step 2
// get the right frame where our "availableDurationImageView" will place in superView
UIView *minTrackView = [self.subviews objectAtIndex:self.subviews.count - 2];
_availableDurationImageView = [[UIImageView alloc] initWithImage:[[UIImage imageNamed:#"MediaSlider.bundle/4_jindu_huancun.png"] resizableImageWithCapInsets:UIEdgeInsetsMake(0, 2, 0, 2)]];
_availableDurationImageView.opaque = NO;
_availableDurationImageView.frame = minTrackView.frame;
[self insertSubview:_availableDurationImageView belowSubview:minTrackView];
}
}
- (void)setAvailableValue:(NSTimeInterval)availableValue
{
if (availableValue >=0 && availableValue <= 1) {
// use "maxLength" and percentage to set our "availableDurationImageView" 's length
_availableDurationImageView.width = _maxLength * availableValue;
}
}

Adding on matt's solution, note that as of iOS 7.0, implementing trackRectForBounds: is rendered impossible. Here is my solution to this problem :
In your UISlider subclass, do this :
-(void)awakeFromNib
{
[super awakeFromNib];
UIImage* clearColorImage = [UIImage imageWithColor:[UIColor clearColor]];
[self setMinimumTrackImage:clearColorImage forState:UIControlStateNormal];
[self setMaximumTrackImage:clearColorImage forState:UIControlStateNormal];
}
with imageWithColor as this function :
+ (UIImage*) imageWithColor:(UIColor*)color
{
return [UIImage imageWithColor:color andSize:CGSizeMake(1.0f, 1.0f)];
}
That will properly take care of this annoying trackRectangle.
I spent too much time looking for a solution to this problem, here's hoping that'll save some time to another poor soul ;).

Here is a solution in Objective C. https://github.com/abhimuralidharan/BufferSlider
The idea is to create a UIProgressview as a property in the UISlider subclass and add the required constraints programatically.
#import <UIKit/UIKit.h> //.h file
#interface BufferSlider : UISlider
#property(strong,nonatomic) UIProgressView *bufferProgress;
#end
#import "BufferSlider.h" //.m file
#implementation BufferSlider
- (instancetype)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
[self setup];
}
return self;
}
-(void)setup {
self.bufferProgress = [[UIProgressView alloc] initWithFrame:self.bounds];
self.minimumTrackTintColor = [UIColor redColor];
self.maximumTrackTintColor = [UIColor clearColor];
self.value = 0.2;
self.bufferProgress.backgroundColor = [UIColor clearColor];
self.bufferProgress.userInteractionEnabled = NO;
self.bufferProgress.progress = 0.7;
self.bufferProgress.progressTintColor = [[UIColor blueColor] colorWithAlphaComponent:0.5];
self.bufferProgress.trackTintColor = [[UIColor lightGrayColor] colorWithAlphaComponent:2];
[self addSubview:self.bufferProgress];
[self setThumbImage:[UIImage imageNamed:#"redThumb"] forState:UIControlStateNormal];
self.bufferProgress.translatesAutoresizingMaskIntoConstraints = NO;
NSLayoutConstraint *left = [NSLayoutConstraint constraintWithItem:self.bufferProgress attribute:NSLayoutAttributeLeft relatedBy:NSLayoutRelationEqual toItem:self attribute:NSLayoutAttributeLeft multiplier:1 constant:0];
NSLayoutConstraint *centerY = [NSLayoutConstraint constraintWithItem:self.bufferProgress attribute:NSLayoutAttributeCenterY relatedBy:NSLayoutRelationEqual toItem:self attribute:NSLayoutAttributeCenterY multiplier:1 constant:0.75]; // edit the constant value based on the thumb image
NSLayoutConstraint *right = [NSLayoutConstraint constraintWithItem:self.bufferProgress attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:self attribute:NSLayoutAttributeTrailing multiplier:1 constant:0];
[self addConstraints:#[left,right,centerY]];
[self sendSubviewToBack:self.bufferProgress];
}
- (instancetype)initWithCoder:(NSCoder *)coder
{
self = [super initWithCoder:coder];
if (self) {
[self setup];
}
return self;
}
#end

for Swift5
First, add tap gesture to slider:
let tap_gesture = UITapGestureRecognizer(target: self, action: #selector(self.sliderTapped(gestureRecognizer:)))
self.slider.addGestureRecognizer(tap_gesture)
Then, implement this function:
#objc func sliderTapped(gestureRecognizer: UIGestureRecognizer) {
let locationOnSlider = gestureRecognizer.location(in: self.slider)
let maxWidth = self.slider.frame.size.width
let touchLocationRatio = locationOnSlider.x * CGFloat(self.slider.maximumValue) / CGFloat(maxWidth)
self.slider.value = Float(touchLocationRatio)
print("New value: ", round(self.slider.value))
}

Related

Not getting UIImageView Rounded Border while Added Multiplier for UIImageViwe

In Storyboard I applied Multiplier for height and width to UIImageView then I just want to rounded border so I used below code its not work for all iPhones.
_profileImgView.clipsToBounds = YES;
_profileImgView.layer.backgroundColor = color.CGColor;
_profileImgView.layer.cornerRadius =_profileImgView.frame.size.width/2;
_profileImgView.layer.borderColor = [UIColor colorWithRed:253.0/255.0 green:182.0/255.0 blue:43.0/255.0 alpha:100].CGColor;
_profileImgView.layer.borderWidth = 5.0f;
Since your corner radius depends on your frame size, you need to update it whenever the frame size changes. If you are using storyboards for your design, you will get the frame size that is in the design when viewDidLoad is called. If the frame size differs for different devices, you will get the final size at a later point in time in the views layoutSubviews or possibly the view controller's viewDidLayoutSubviews.
My suggested solution is to sub-class UIImageView and put the specifics for the image view in awakeFromNib and layoutSubviews, then use this class instead of UIImageView where appropriate.
// CircularImageView.h
#import <UIKit/UIKit.h>
#interface CircularImageView : UIImageView
#end
// CircularImageView.m
#implementation CircularImageView
- (void)awakeFromNib {
[super awakeFromNib];
self.clipsToBounds = YES;
self.layer.borderColor = [UIColor colorWithRed:253.0/255.0 green:182.0/255.0 blue:43.0/255.0 alpha:100].CGColor;
self.layer.borderWidth = 5.0f;
}
- (void)layoutSubviews {
[super layoutSubviews];
self.layer.cornerRadius = self.frame.size.width / 2;
}
#end
implement this code in same Viewcontroller class it is work for me
-(void)viewDidLayoutSubviews
{
[super viewDidLayoutSubviews];
_profileImgView.clipsToBounds = YES;
_profileImgView.layer.backgroundColor = color.CGColor;
_profileImgView.layer.cornerRadius =_profileImgView.frame.size.width/2;
_profileImgView.layer.borderColor = [UIColor colorWithRed:253.0/255.0 green:182.0/255.0 blue:43.0/255.0 alpha:100].CGColor;
_profileImgView.layer.borderWidth = 5.0f;
}

Content padding in custom view with Cocoa auto layout

I have a custom NSView subclass which has a border around itself. The border is drawn inside this view. Is it possible to respect this borders with auto layout?
For example, when I place the subview to my custom view and set constraints like this:
#"H:|-(myViewSubView)-|" (not #"H:|-(myViewBorderWidth)-(myViewSubView)-(myViewBorderWidth)-|")
#"V:|-(myViewSubView)-|"
the layout must be:
Horizontal: |-(myViewBorderWidth)-|myViewSubview|-(myViewBorderWidth)-|
Vertical: |-(myViewBorderWidth)-|myViewSubview|-(myViewBorderWidth)-|
I've tried to overwrite -bounds method in my view to return the bounds rect without the borders, but it doesn't help.
UPDATE
I just noticed that your question is talking about NSView (OS X), not UIView (iOS). Well, this idea should still be applicable, but you won't be able to drop my code into your project unchanged. Sorry.
ORIGINAL
Consider changing your view hierarchy. Let's say your custom bordered view is called BorderView. Right now you're adding subviews directly to BorderView and creating constraints between the BorderView and its subviews.
Instead, give the BorderView a single subview, which it exposes in its contentView property. Add your subviews to the contentView instead of directly to the BorderView. Then the BorderView can lay out its contentView however it needs to. This is how UITableViewCell works.
Here's an example:
#interface BorderView : UIView
#property (nonatomic, strong) IBOutlet UIView *contentView;
#property (nonatomic) UIEdgeInsets borderSize;
#end
If we're using a xib, then we have the problem that IB doesn't know that it should add subviews to the contentView instead of directly to the BorderView. (It does know this for UITableViewCell.) To work around that, I've made contentView an outlet. That way, we can create a separate, top-level view to use as the content view, and connect it to the BorderView's contentView outlet.
To implement BorderView this way, we'll need an instance variable for each of the four constraints between the BorderView and its contentView:
#implementation BorderView {
NSLayoutConstraint *topConstraint;
NSLayoutConstraint *leftConstraint;
NSLayoutConstraint *bottomConstraint;
NSLayoutConstraint *rightConstraint;
UIView *_contentView;
}
The contentView accessor can create the content view on demand:
#pragma mark - Public API
- (UIView *)contentView {
if (!_contentView) {
[self createContentView];
}
return _contentView;
}
And the setter can replace an existing content view, if there is one:
- (void)setContentView:(UIView *)contentView {
if (_contentView) {
[self destroyContentView];
}
_contentView = contentView;
[self addSubview:contentView];
}
The borderSize setter needs to arrange for the constraints to be updated and for the border to be redrawn:
- (void)setBorderSize:(UIEdgeInsets)borderSize {
if (!UIEdgeInsetsEqualToEdgeInsets(borderSize, _borderSize)) {
_borderSize = borderSize;
[self setNeedsUpdateConstraints];
[self setNeedsDisplay];
}
}
We'll need to draw the border in drawRect:. I'll just fill it with red:
- (void)drawRect:(CGRect)rect {
CGRect bounds = self.bounds;
UIBezierPath *path = [UIBezierPath bezierPathWithRect:bounds];
[path appendPath:[UIBezierPath bezierPathWithRect:UIEdgeInsetsInsetRect(bounds, self.borderSize)]];
path.usesEvenOddFillRule = YES;
[path addClip];
[[UIColor redColor] setFill];
UIRectFill(bounds);
}
Creating the content view is trivial:
- (void)createContentView {
_contentView = [[UIView alloc] init];
[self addSubview:_contentView];
}
Destroying it is slightly more involved:
- (void)destroyContentView {
[_contentView removeFromSuperview];
_contentView = nil;
[self removeConstraint:topConstraint];
topConstraint = nil;
[self removeConstraint:leftConstraint];
leftConstraint = nil;
[self removeConstraint:bottomConstraint];
bottomConstraint = nil;
[self removeConstraint:rightConstraint];
rightConstraint = nil;
}
The system will automatically call updateConstraints before doing layout and drawing if somebody has called setNeedsUpdateConstraints, which we did in setBorderSize:. In updateConstraints, we'll create the constraints if necessary, and update their constants based on borderSize. We also tell the system not to translate the autoresizing masks into constraints, because that tends to create unsatisfiable constraints.
- (void)updateConstraints {
self.translatesAutoresizingMaskIntoConstraints = NO;
self.contentView.translatesAutoresizingMaskIntoConstraints = NO;
[super updateConstraints];
if (!topConstraint) {
[self createContentViewConstraints];
}
topConstraint.constant = _borderSize.top;
leftConstraint.constant = _borderSize.left;
bottomConstraint.constant = -_borderSize.bottom;
rightConstraint.constant = -_borderSize.right;
}
All four constraints are created the same way, so we'll use a helper method:
- (void)createContentViewConstraints {
topConstraint = [self constrainContentViewAttribute:NSLayoutAttributeTop];
leftConstraint = [self constrainContentViewAttribute:NSLayoutAttributeLeft];
bottomConstraint = [self constrainContentViewAttribute:NSLayoutAttributeBottom];
rightConstraint = [self constrainContentViewAttribute:NSLayoutAttributeRight];
}
- (NSLayoutConstraint *)constrainContentViewAttribute:(NSLayoutAttribute)attribute {
NSLayoutConstraint *constraint = [NSLayoutConstraint constraintWithItem:_contentView attribute:attribute relatedBy:NSLayoutRelationEqual toItem:self attribute:attribute multiplier:1 constant:0];
[self addConstraint:constraint];
return constraint;
}
#end
I have put a complete working example in this git repository.
For future reference, you can override NSView.alignmentRectInsets to affect the position of the layout guides:
Custom views that draw ornamentation around their content can override
this property and return insets that align with the edges of the
content, excluding the ornamentation. This allows the constraint-based
layout system to align views based on their content, rather than just
their frame.
Link to documentation:
https://developer.apple.com/documentation/appkit/nsview/1526870-alignmentrectinsets
Have you tried setting the intrinsic size to include the border size?
- (NSSize)intrinsicContentSize
{
return NSMakeSize(width+bordersize, height+bordersize);
}
then you would set the content compression resistance priorities in both directions to be required:
[self setContentCompressionResistancePriority:NSLayoutPriorityRequired forOrientation:NSLayoutConstraintHorizontal];
[self setContentCompressionResistancePriority:NSLayoutPriorityRequired forOrientation:NSLayoutConstraintVertical];
The one solution I found is to overload the addConstraint: method and modify constraints before they'll be added:
- (void)addConstraint:(NSLayoutConstraint *)constraint
{
if(constraint.firstItem == self || constraint.secondItem == self) {
if(constraint.firstAttribute == NSLayoutAttributeLeading) {
constraint.constant += self.leftBorderWidth;
} else if (constraint.firstAttribute == NSLayoutAttributeTrailing) {
constraint.constant += self.rightBorderWidth;
} else if (constraint.firstAttribute == NSLayoutAttributeTop) {
constraint.constant += self.topBorderWidth;
} else if (constraint.firstAttribute == NSLayoutAttributeBottom) {
constraint.constant += self.bottomBorderWidth;
}
}
[super addConstraint:constraint];
}
And then also handle this constraints in xxxBorderWidth setters.

CAEmitterLayer not visible in my View Controller

I'm trying to add a simple particle effect overlay to one of my UIViewController instances. I've followed a couple of tutorials I found, but neither of them deal with view controllers and their storyboards are just a view out on its own with no controller, which is confusing.
Here's my code, I'm just trying to figure out why I can't see the particle effects. What am I missing? The view itself is definitely there and added (if I change its color or something I can see it), it's just empty, and isn't showing any particle effects. The image file referenced is definitely in the project and target, so what else have I done wrong here? Do I need to add the CAEmitterLayer to rainView somehow? The tutorials didn't offer any help on this part!
RainfallOverlay.h
#import <UIKit/UIKit.h>
#import <QuartzCore/QuartzCore.h>
#interface RainfallOverlay : UIView {
CAEmitterLayer *rainEmitter;
}
#end
RainfallOverlay.m
#import "RainfallOverlay.h"
#implementation RainfallOverlay
- (void) awakeFromNib
{
rainEmitter = (CAEmitterLayer *) self.layer;
rainEmitter.emitterPosition = CGPointMake(160, 100);
rainEmitter.emitterSize = CGSizeMake(10, 10);
rainEmitter.renderMode = kCAEmitterLayerAdditive;
CAEmitterCell *rain = [CAEmitterCell emitterCell];
rain.birthRate = 200;
rain.lifetime = 2.0;
rain.lifetimeRange = 1.5;
rain.color = [[UIColor colorWithRed: 0.2 green: 0.4 blue: 0.8 alpha: 0.1] CGColor];
rain.contents = (id) [[UIImage imageNamed: #"Particles_rain.png"] CGImage];
rain.name = #"rain";
rain.velocity = 150;
rain.velocityRange = 100;
rain.emissionRange = M_PI_2;
rain.emissionLongitude = 0.025 * 180 / M_PI;
rain.scaleSpeed = 0;
rain.spin = 0.5;
rainEmitter.emitterCells = [NSArray arrayWithObject: rain];
}
#end
ViewController.m viewDidLoad
RainfallOverlay *rainView = [[RainfallOverlay alloc] initWithFrame: CGRectMake(0, 0, 320, 250)];
[rainView setUserInteractionEnabled: NO];
[self.view bringSubviewToFront: rainView];
[self.view addSubview: rainView];
There are 2 problems:
awakeFromNib would only be called if the view is loaded from a nib file. In your case, you have to implement initWithFrame.
You have to override layerClass to that self.layer returns a CAEmitterLayer. Just casting the layer to CAEmitterLayer does not work.
So your RainfallOverlay implementation should look like this:
+ (Class)layerClass
{
return [CAEmitterLayer class];
}
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
rainEmitter = (CAEmitterLayer *) self.layer;
// ... remaining setup
}
return self;
}

Change the height of NavigationBar and UIBarButtonItem elements inside it in Cocoa Touch

I suppose it's not strictly in line with Apple guidelines but I guess it must be possible somehow. I'd like to change the height of navigation bar inside UINavigationController and the height of UIBarButtonItem elements inside that bar.
Using a trick from this question I managed to change the height of navigation bar but I can see no way of adjusting the height of bar button items.
If anyone knows how to change the size of bar button items, please help me out.
This is my solution. It works very well.
#interface UINavigationBar (CustomHeight)
#end
#implementation UINavigationBar (CustomHeight)
- (CGSize)sizeThatFits:(CGSize)size {
// Change navigation bar height. The height must be even, otherwise there will be a white line above the navigation bar.
CGSize newSize = CGSizeMake(self.frame.size.width, 40);
return newSize;
}
-(void)layoutSubviews {
[super layoutSubviews];
// Make items on navigation bar vertically centered.
int i = 0;
for (UIView *view in self.subviews) {
NSLog(#"%i. %#", i, [view description]);
i++;
if (i == 0)
continue;
float centerY = self.bounds.size.height / 2.0f;
CGPoint center = view.center;
center.y = centerY;
view.center = center;
}
}
Maybe this tutorial about a customized navbar will help you: Recreating the iBooks wood themed navigation bar
If you create a BarButtonItem with a UIImageView you can maybe change the framesize/boundsize of the custom UIImageView
UIImageView* imageView = [[[UIImageView alloc] initWithFrame:navigationController.navigationBar.frame] autorelease];
imageView.contentMode = UIViewContentModeLeft;
imageView.image = [UIImage imageNamed:#"NavBar-iPhone.png"];
[navigationController.navigationBar insertSubview:imageView atIndex:0];
So for your need you would give the -initWithFrame method appropriate values.
static CGFloat const CustomNavigationBarHeight = 74;
#implementation WTNavigationBar
- (CGSize)sizeThatFits:(CGSize)size{
size.width = 1024;
size.height = CustomNavigationBarHeight;
return size;
}
-(void)layoutSubviews {
[super layoutSubviews];
for (UIView *view in self.subviews) {
SFLog(#"view.class=%#",[view class]);
if ([view isKindOfClass:NSClassFromString(#"UINavigationItemButtonView")]) {
float centerY = self.bounds.size.height / 2.0f;
CGPoint center = view.center;
center.y = centerY;
view.center = center;
}
}
}
#end
in my iPad app,which has a fixed landscape orientation,I found I have to hardcode the size's width
I managed to do something similar by subclassing UINavigationBar and overriding -layoutSubviews. The code looks like:
-(void)layoutSubviews {
[super layoutSubviews];
int i = 0;
for (UIView *view in self.subviews) {
NSLog(#"%i. %#", i++, [view description]);
if ([view isKindOfClass:NSClassFromString(#"UINavigationButton")]) {
view.frame = CGRectMake(0, 0, 100, 50);
}
}
}
If you need to know how to subclass UINavigationBar, have a look at this very good answer.
I am not really sure about the NSClassFromString(#"UINavigationButton")] part. It works, but I did this as an experiment, and I'm not sure if this will get approved by Apple. I hope someone with a better knowledge might shed some light.
For the UINavigationbar
In iOS SDK 4.3 and beyond, there is a way (hack) to change the height of the UINavigationBar.
To change the height of UINavigationController, change its frame size in viewWillAppear:animated: function. Then, the height will stay customized throughout whole app.
For the UIBarButtonItems
I've actually run into this myself and the only thing I could come up with was leveraging initWithCustomView and passing in a UIButton with a defined frame.
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
/*
* Insert button styling
*/
button.frame = CGRectMake(0, 0, width, height);
UIBarButtonItem *barButtonItem = [[UIBarButtonItem alloc] initWithCustomView:button];
Otherwise UIBarButtonItem only has a width property that can be set but unfortunately not a height property. Another nifty thing I've done with initWithCustomView is to pass in a toolbar with a button and other things like activity indicators. Hope this helps.
How badly do you want this? And, how thin (or thick) do you want to make your navbar?
One approach would be to set the transform of the navbar to scale and translate it. If you scale it too much the title and button text will look wonky, but if you only need to shave a few pixels you might be allright.
Here's the result of scaling it to be 75% of full height (33 pixels tall):
And the code that produced this:
- (void)viewDidLoad
{
[super viewDidLoad];
self.navigationItem.title = #"Thin Navigation Bar";
self.navigationItem.rightBarButtonItem = [[[UIBarButtonItem alloc] initWithTitle: #"Press Me" style:UIBarButtonItemStyleBordered target: nil action: NULL ] autorelease];
CGFloat scale = .75;
CGFloat cy = 44.0 - ( 44.0 * scale );
self.navigationController.navigationBar.transform = CGAffineTransformScale( CGAffineTransformMakeTranslation( 0, -cy / 2.0 ), 1.0, scale ) ;
}
- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
CGFloat scale = .75;
CGFloat cy = 44.0 - ( 44.0 * scale );
CGRect r = self.view.frame;
r.origin.y -= cy;
r.size.height += cy;
self.view.frame = r;
}
Now, this does have a number of problems, which may or may not be solvable. #1 is that you're fighting with the UINavigationController to size and position the navbar and the view-controller views. Animating between view controllers that use this technique is likely going to look weird.
I'd be curious if you could solve the related issues...
One last thought: If you dont use a UINavigationController then there really aren't a whole lot of issues with this other than squished text. Or, you could use a navigation controller but hide the default navbar, and add the thin navbar to each of your child-view controller views. You could even subclass UINavigationBar and set the transform from within:
#interface TSThinNavBar : UINavigationBar
{
}
#end
#implementation TSThinNavBar
// assuming we'll always be constructed from a nib
- (id) initWithCoder:(NSCoder *)aDecoder
{
self = [super initWithCoder: aDecoder];
if ( self != nil )
{
CGFloat scale = .75;
CGFloat cy = 44.0 - ( 44.0 * scale );
self.transform = CGAffineTransformScale( CGAffineTransformMakeTranslation( 0, -cy / 2.0 ), 1.0, scale ) ;
}
return self;
}
#end

CGAffineTransformMakeScale Makes UIView Jump to Original Size before scale

I have a UIView that I set up to respond to pinch gestures and change its size, except, once you enlarge it and then try and pinch it again, it jumps to its original size (which just so happens to be 100x200). Here is the code:
#implementation ChartAxisView
- (id)initWithFrame:(CGRect)frame {
if ((self = [super initWithFrame:frame])) {
// do gesture recognizers
UIPinchGestureRecognizer *pinch = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:#selector(onPinch:)];
[self addGestureRecognizer:pinch];
[pinch release];
}
return self;
}
- (void)drawRect:(CGRect)rect {
CGContextRef context = UIGraphicsGetCurrentContext();
CGColorRef redColor = [UIColor colorWithRed:1.0 green:0.0 blue:0.0 alpha:1.0].CGColor;
CGContextSetFillColorWithColor(context, redColor);
CGContextFillRect(context, self.bounds);
}
- (void)onPinch: (UIPinchGestureRecognizer*) gesture {
self.transform = CGAffineTransformMakeScale(gesture.scale, gesture.scale);
}
- (void)dealloc {
[super dealloc];
}
#end
Any thoughts?
So there are two types of Scale (or, transform in general) functions: CGAffineTransformMakeScale and CGAffineTransformScale
The first one, CGAffineTransformMakeScale which you are using, always transforms with respect to the image's original size. And that is why you see the jump to its original size before the scaling happens.
The second one, CGAffineTransformScale, transforms from the image's current position. This is what you need. For this, it requires an additional 'transform' arg. The 'transform' arg in your case represents the enlarged image.
Read this very informative blog post about transformations.
- (void)onPinch: (UIPinchGestureRecognizer*) gesture {
if ([gesture state] == UIGestureRecognizerStateBegan)
{
curTransform = self.transform;
}
self.transform = CGAffineTransformScale(curTransform,gesture.scale, gesture.scale);
}
use CGAffineTransformScale instead of CGAffineTransformMakeScale
you will need a member -> CGAffineTransform curTransform;
;)
you can set transform with following code:
ivClone setTransform:CGAffineTransformMakeScale(scale, scale)];
and you can get current transform with following coee:
newV.transform.a //x scale
newV.transform.d // y scale