Isn't UIButton supposed to become grayish/grayer when enabled=NO ?
I have a simple UIButton on a blackbackground (no custom images, no custom nothing, just dragged it with IB and changed size and title).
And when I set it programatically to become disabled it stays white as hell!
For now I'm using a small stupid workaround: hidden blackbg 0,5 alpha UIView on top of the button that becomes hidden=NO when I need to disable the button... but I would like to set the button properly...
Any thoughts?
There is another way without having to alpha the whole button:
[startButton setTitleColor:[UIColor grayColor] forState:UIControlStateDisabled];
Then whenever you set the enabled property to NO, the button's text will automatically gray out.
There is no way to make a UIButton "grayer". But you can use that trick :
UIButton *myButton;
myButton.alpha = 0.4;
myButton.enabled = NO;
So your UIButton looks like unusable ;)
Simply make a UIButton category like the following and import #import "UIButton+StateColors.h" in the classes where you want to use it.
.h
#import <UIKit/UIKit.h>
#interface UIButton (StateColors)
-(void)makeDisabled:(BOOL)flag;
#end
.m
#import "UIButton+StateColors.h"
#define ENABLED_BUTTON_ALPHA 1
#define DISABLED_BUTTON_ALPHA 0.3
#implementation UIButton (StateColors)
-(void)makeDisabled:(BOOL)flag {
self.enabled = !flag;
self.alpha = flag ? DISABLED_BUTTON_ALPHA : ENABLED_BUTTON_ALPHA;
}
#end
And use it like this...
[self.emailBtn makeDisabled:NO];
[self.printBtn makeDisabled:YES];
It's a universal solution I hope...
I happened upon this question and Apple has published a new UIKit User Interface Catalog for working with Buttons in iOS 7.
In response to your question, the UIButton Class now exposes a property called adjustsImageWhenDisabled, which is "a Boolean value that determines whether the image changes when the button is disabled."
If this adjustsImageWhenDisabled property is set to "YES, the image is drawn darker when the button is disabled. The default value is YES."
I face the same problem because I had set background color.
I removed the background color and set it for UIControlStateNormal only and the default behaviour for enable/disable started to appear.
If you are setting background color instead of image try this category for converting UIColor to UIImage:
copied from here:
+ (UIImage *)imageWithColor:(UIColor *)color
{
CGRect rect = CGRectMake(0.0f, 0.0f, 1.0f, 1.0f);
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, [color CGColor]);
CGContextFillRect(context, rect);
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
then use this:
[self.loginButton setBackgroundImage:[UIImage imageWithColor:greenColor] forState:UIControlStateNormal];
self.loginButton.enabled = NO;
to set the color as background. Now when you enable/disable, the gray effect should appear.
Related
Its a very basic question - but i could not find the answer to it anywhere.
I would like a back button like the default one that shows up in a navigation bar, but with a image in the background.
Even with customization, how to calculate the size/length of the button as per the title?
Thanks a ton for the help,in advance!
UPDATE:
Thanks guys! but the answer that i finally implemented was this:
#implementation UINavigationBar (UINavigationBarCategory)
-(void)drawRect:(CGRect)rect
{
UIColor *color = [UIColor colorWithRed:(13.0/255.0) green:(183.0/255.0) blue:(255.0/255.0) alpha:1.0];
// use a custom color for the back button which i got using the digital color meter on my nav bar image :P
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColor(context, CGColorGetComponents( [color CGColor]));
CGContextFillRect(context, rect);
self.tintColor = color;
// use a custom background image for my navigation bar
UIImage *img = [UIImage imageNamed: Navigation_img];
[img drawInRect:CGRectMake(0,0,img.size.width,img.size.height)];
}//worked satisfactorily for me
#end
Create a UIButton using your own UIImage to mimic the shape you want.
The UIImage must be a stretchable type, that is, you would set the leftCapWidth to be the size of your back arrow
Set the UIButton's title to whatever you like
Create a new UIBarButtonItem using your new button as a custom view
Set this to your navigationItems leftBarButtonItem property.
The button will automatically size to fit your title.
Use sizeWithFont: NSString method to calculate the size of the title.
See NSString UIKit Additions Reference
To find out the width of specific text, you may use following methods.
NSString *str=#"Back";
CGSize sizeOfBack = [str sizeWithFont:[UIFont systemFontOfSize:14] constrainedToSize:CGSizeMake(30, CGFLOAT_MAX) lineBreakMode:UILineBreakModeWordWrap];
Let me explain above two statements.
the text that you want to have in your string.
sizewithfont method will allow you to calculate the size.
Here, sizeOfBack.width will give me the width acquired by 14System sized string.
Hope it helps to you. let me know by comments, if you have yet doubts regarding this.
I have read this and change UINavigationBar's background:
#implementation UINavigationBar (CustomImage)
- (void)drawRect:(CGRect)rect {
UIImage *image = [UIImage imageNamed: #"top-with-logo.png"];
[image drawInRect:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
}
#end
you see, I add a image named top-with-logo.png, and I want to change the background view by adding an image named top-without-logo.png. But the code above will change the background forever and i cannont change any more. Do you know how?
Thank you very much.
I'm not sure I understand what you mean, but you can place a Boolean ivar on your app's delegate. then in the function you load top-with-logo.png if it's true/false and load top-without-logo.png if it's the other value. then, when you want to change the logo, just change the Boolean's value and call setNeedsDisplay on the navigationBar.
if you use xib files, you can also subclass UINavigationBar, and instead of using a catagory you override the drawRect function and place the variable as an instance variable as a subclass, I believe it is cleaner, but you can only set that up in Interface builder ( otherwise there's no way to tell a UINavigationController to use a different class for the navigationBar property )
You can use,
UINavigationBar *navigationBar = self.navigationController.navigationBar;
UIImage *image = [UIImage imageNamed: #"NavBar-Wood.png"];
[navigationBar setBackgroundImage:image forBarMetrics: UIBarMetricsDefault];
self.navigationController.navigationBar.tintColor = [UIColor brownColor];
I understand that the only way to change the color of the text of the back button is to make your own custom button:
self.navigationItem.backBarButtonItem = yourCustomBackButton;
My question is: How do I create a back button that takes tint color into account and looks exactly the same as the default back button except for the color of the text (unless it's white)?
Add a category to the UINavigationBar and set it's background color there. This code also shows how to use an image.
#implementation UINavigationBar (UINavigationBarCategory)
- (void)drawRect:(CGRect)rect {
/***
// use a custom color
UIColor *color = [UIColor colorWithRed:.455 green:.365 blue:0 alpha:.9];
3 CGContextRef context = UIGraphicsGetCurrentContext();
4 CGContextSetFillColor(context, CGColorGetComponents( [color CGColor]));
5 CGContextFillRect(context, rect);
6 self.tintColor = color;
***/
// use a custom background image
UIImage *img = [UIImage imageNamed: [PlistVariables sharedInstance].navbarBackgroundImageName ];
[img drawInRect:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
self.tintColor = [PlistVariables sharedInstance].navbarTintColor;
}
Here's some sample output using RGB 192,93,0 for background brown:
It's really not possible to change the text color of the back button. You can however assign a custom view to the leftBarButtonItem property. I've put together a simple little project showing how to do that that recreates the in/out animation of the standard iOS UI. Takes a bit of hacking, but you should be able to assign a button with a label in it to the custom view and update that.
https://github.com/typeoneerror/BBCustomBackButtonViewController
Basically I want a custom UINavigationBar. I don't want it to be "translucent" or anything, like the pictures app.
I basically want to completely remove it, but I still want to be able to add back buttons and such when navigation controllers are pushed, and I want the views (EG: UITableViewController) to be pushed down below it.
Like this:
Any ideas how to achieve this at all?
Thanks
#implementation UINavigationBar (background)
- (void)drawRect:(CGRect)rect {
UIImage *image = [UIImage imageNamed:#"navigationbar.png"];
[image drawInRect:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
}
#end
basically, its not completely see through - its a visual lie. The only way to do it realistically is to override UINavigationBar's drawRect: method, as shown above.
To see through the UINavigationBar, if you choose to have one, just:
self.navigationController.navigationBar.translucent=YES;
You'll have to change the tint/color to match the background if you want it to appear like the image you posted.
At the beginning of your AppDelegate subclass UINavigationBar as below:
#interface CustomNavBar : UINavigationBar
#end
#implementation CustomNavBar
- (void)drawRect:(CGRect)rect {
UIImage *image = [UIImage imageNamed:#"bar.png"];
[image drawInRect:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
}
and then in the AppDelegate do this magic:
//Set custom NavigationBar
[self.navController setValue:[[CustomNavBar alloc]init] forKeyPath:#"navigationBar"];
//Set tint to match bar.png
self.navController.navigationBar.tintColor = [UIColor colorWithRed:0.93 green:0.43 blue:0 alpha:1];
//Set font for NavigationBar
[self.navController.navigationBar setTitleTextAttributes:[NSDictionary dictionaryWithObjectsAndKeys:[UIFont fontWithName:#"Comfortaa-Bold" size:20], UITextAttributeFont, nil]];
That should give you a lot more control over UINavigationController look & feel.
Hard to tell, could be the UINavigationBar is there and color matches the UIView background or, there is no UINavigationBar, just a view with custom buttons and UILabel on top. Pick an approach and code it, or ask the question again with more specifics.
When you try deleting a note in iPhone's Notes application, an UIActionSheet pops up. The sheet is translucent (but not black translucent). How is that achieved? Is it possible to make the background of UIActionSheet a certain color?
I usually implement the following delegate method:
- (void)willPresentActionSheet:(UIActionSheet *)actionSheet
Just to make a sample. In this case I use a stretched png as a background:
- (void)willPresentActionSheet:(UIActionSheet *)actionSheet {
UIImage *theImage = [UIImage imageNamed:#"detail_menu_bg.png"];
theImage = [theImage stretchableImageWithLeftCapWidth:32 topCapHeight:32];
CGSize theSize = actionSheet.frame.size;
// draw the background image and replace layer content
UIGraphicsBeginImageContext(theSize);
[theImage drawInRect:CGRectMake(0, 0, theSize.width, theSize.height)];
theImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
[[actionSheet layer] setContents:(id)theImage.CGImage];
}
and this is the result:
alt text http://grab.by/4yF1
You can use the code below:
actionSheetObj.actionSheetStyle=UIActionSheetStyleBlackOpaque;
or
actionSheetObj.actionSheetStyle=UIActionSheetStyleBlackTranslucent;
actionSheetObj.actionSheetStyle=UIActionSheetStyleBlackTranslucent;
It's not too difficult. You can use the following code:
CGSize mySize = myActionSheet.bounds.size;
CGRect myRect = CGRectMake(0, 0, mySize.width, mySize.height);
UIImageView *redView = [[[UIImageView alloc] initWithFrame:myRect] autorelease];
[redView setBackgroundColor:[UIColor colorWithRed:1.0 green:0.0 blue:0.0 alpha:0.5]];
[myActionSheet insertSubview:redView atIndex:0];
Just make sure you present the UIActionSheet before doing this or the size wont be set. That makes it kind of ugly, but you could do something like:
[myActionSheet showInView:self.view];
if (!redAdded) {
redAdded = YES;
//THE ABOVE CODE GOES HERE
}
You can definitely adjust the opacity by setting the alpha value. Interface Builder lets you edit the value directly, but in code I think you would do:
[[myActionSheet view] setOpaque:NO];
[[myActionSheet view] setAlpha:0.5];
I'm not sure if you need the setOpaque call or not - I think that is used to help optimize performance, as the iPhone won't try to render anything hidden by the opaque view.
It looks black to me (note: using 2.2.1). The only reason there's a color to it is because of the yellow behind it.
One option would be to use the black transparent background and find out the size and speed of the action sheet. Then create a view and animate it in at the same time you show the action sheet, just underneath it, to give it a tint different than the color naturally behind the action sheet. You would have to make the color view also translucent so you could see behind that as well.
I'm not sure if you can, but you might also try adjusting the opacity of the action sheet itself as well.