I am trying something like below
UIView * view = [UIView new];
view.frame = CGRectMake(50, 50, 200, 200);
view.bounds = CGRectMake(0, 0, 400, 400);
view.backgroundColor = [UIColor grayColor];
UIButton * btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[btn setFrame:CGRectMake(50, 50, 300, 50)];
[btn setTitle:#"Button" forState:UIControlStateNormal];
[view addSubview:btn];
CALayer * layer = [view layer];
[layer drawInContext:ctx];
My questions is
1) Like we draw images or text with CGContextRef , can we draw a UIView instance the same way ?
I am not so familliar with the core graphics framework , so please let me know the possibilities . My basic aim is to be able to draw custom views in drawRect using CGContextRef by any means .
Thank you in advance !!!
You have to implement -(void)drawRect:(CGRect)rect method in your subclass of UIView. In this method you should draw to the current context.
Related
I have seen this answer
https://stackoverflow.com/a/9243472/563381
And while it works well visual as soon as you set the mask on the Navigation bar's layer it no longer responds to touches... So the back button that appears on the bar can't be clicked. Any solution to cause touches to go through a CALAyer? I didnt think CALayer's blocked touches or that a mask would ever block touches.
Well, I really don't know why CALayer blocks touches and this sounds odd to me...
The way I round corners of UINavigationBar consists in putting 2 UIImageView (10x10 pixels) in the corners and add 2 images to them. These images work as a mask, without blocking touches. If you use antialiasing to draw your images, the look is perfect.
You should try to use this code:
self.navigationController.navigationBar.translucent = YES;
This wil turn on your back button.You can see your button, but its in another layer. That's why it will not work the touches..
UPDATE:
Use this line of code for test. This will work like a charm for you.
//Style UINavigationBar
UIView *background = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 320, 44)];
background.backgroundColor = [UIColor blackColor];
[self.view addSubview:background];
self.navigationController.navigationBar.tintColor = [UIColor cyanColor];
self.navigationController.navigationBar.translucent = YES;
CALayer *capa = [self.navigationController navigationBar].layer;
[capa setShadowColor: [[UIColor blackColor] CGColor]];
[capa setShadowOpacity:0.85f];
[capa setShadowOffset: CGSizeMake(0.0f, 1.5f)];
[capa setShadowRadius:2.0f];
[capa setShouldRasterize:YES];
//Round
CGRect bounds = capa.bounds;
bounds.size.height += 10.0f; //I'm reserving enough room for the shadow
UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:bounds
byRoundingCorners:(UIRectCornerTopLeft | UIRectCornerTopRight)
cornerRadii:CGSizeMake(10.0, 10.0)];
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.frame = bounds;
maskLayer.path = maskPath.CGPath;
[capa addSublayer:maskLayer];
capa.mask = maskLayer;
//Back Btn
UIButton *btnback = [UIButton buttonWithType:UIButtonTypeCustom];
[btnback setFrame:CGRectMake(0, 0, 54, 29)];
[btnback setBackgroundImage:[UIImage imageNamed:#"back.png"] forState:UIControlStateNormal];
UILabel * btnlabel = [[UILabel alloc]initWithFrame:CGRectMake(15, 0, 40, 23)];
btnlabel.backgroundColor = [UIColor clearColor];
btnlabel.textColor = [UIColor whiteColor];
btnlabel.font = [UIFont boldSystemFontOfSize:13];
btnlabel.text = #"back";
[btnback addSubview:btnlabel];
[btnback addTarget:self action:#selector(backHome:) forControlEvents:UIControlEventTouchUpInside];
self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc]initWithCustomView:btnback];
Please check below image. i have added scrollview in "BLACK" color and added subview in "GREY" color. now i want to make subview transparent which is define as "WHITE" color.
Please refer the below code. Let me know how to make button transparent with particular frame or let me know if you have any alternative for that.
self.scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0.0, 40.0, self.frame.size.width, 300.0)];
self.scrollView.contentSize = CGSizeMake(self.bounds.size.width,ViewHeight);
self.scrollView.autoresizingMask=UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
self.scrollView.delegate = self;
self.scrollView.backgroundColor =[UIColor blackColor];
[self.view addSubview:self.scrollView
UIButton *butApp = [UIButton buttonWithType:UIButtonTypeCustom];
[butApp setFrame:CGRectMake(x, y , w, h)];
[butApp setBackgroundColor:[UIColor greyColor]];
[self.scrollView addSubview:butApp];
UIButton* gapButton = [UIButton buttonWithType:UIButtonTypeCustom];
[gapButton setFrame:CGRectMake(x+3, y+10, w-6, 10)];
[gapButton setBackgroundColor:[UIColor whiteColor]];
[self.scrollView addSubview:gapButton];
Instead of this gapButton i need transparent portion in grey color so user can see black color in that portion.
Try this, I suggested it in comments. Other answer requires subclassing UIButton, which you suggested was not ideal in your situation.
UIButton *butApp = [UIButton buttonWithType:UIButtonTypeCustom];
[butApp setFrame:CGRectMake(x, y , w, h)];
//[butApp setBackgroundColor:[UIColor greyColor]]; //replace this...
[butApp setBackgroundImage:[UIImage imageNamed:#"greyWithHoleInCenter.png"]
forState:UIControlStateNormal]; //...with this
[self.scrollView addSubview:butApp];
I created a crude .png file to represent the kind of backgroundImage you might be looking for. Note that the center is clear, not white. Therefore, it should show whatever image is behind it:
Ok. Funny question. In my opinion you have to override drawRect: + drawInContext: methods by subclassing UIView class.
You also need to set the container view (the gray view) + button bg to clearColor
-(void)drawRect:(CGRect)r
{
// Let this method blank will cause drawLayer:InContext to be called
}
-(void)drawLayer:(CALayer*)layer inContext:(CGContextRef)context
{
// Fill the bg with gray
CGContextSetFillColorWithColor(context, [UIColor grayColor].CGColor);
CGContextFillRect(context, self.bounds);
// I clear the subview frames
for (UIView * v in [self subviews]) // I do it for all subviews
{
CGContextSetBlendMode(context, kCGBlendModeClear);
CGContextFillRect(context, v.frame);
}
}
I am trying to add a non-standard color to the cell when its highlighted. FOr this i create a view with the background color that i want and set it as the selectedBackgroundView for the cell.
All is fine.
UIView *selectionView = [[UIView alloc] init];
[selectionView setBackgroundColor:[UIColor colorWithRed:(121/255.0) green:(201/255.0) blue:(209/255.0) alpha:1.0]];
[cell setSelectedBackgroundView:selectionView];
My question, can i change the frame of the selectedBackgroundView so that it highlights only a part of the cell (to be precise, i want the selectionBackroundView to have an X-offset of 20 pixels).
is there any easy way of doing this ?
Updated code :
UIView *selectionView = [[UIView alloc] init];
[selectionView setBackgroundColor:[UIColor clearColor]];
UIView *selectionSubView = [[UIView alloc] initWithFrame:(CGRectMake(20.0f, 0.0f, 300.0f, 72.0f))];
[selectionSubView setBackgroundColor:[UIColor colorWithRed:(121/255.0) green:(201/255.0) blue:(209/255.0) alpha:1.0]];
UIView *clearView = [[UIView alloc] initWithFrame:(CGRectMake(0.0f, 0.0f, 20.0f, 72.0f))];
[clearView setBackgroundColor: [UIColor clearColor]];
[selectionView addSubview: selectionSubView];
[selectionView addSubview: clearView];
[cell setSelectedBackgroundView: selectionView];
THis doesn seem to work either. I have added this code in the 'cellForRowAtIndexPath'
Thanks in advance
You could put a smaller UIView as subview of your selectionView and change tha background color of that view.
You can do like this.
You create the separate file for UIView as below.
TestView.m
- (id)initWithFrame:(CGRect)frame {
self = [super initWithFrame:frame];
if (self) {
// Initialization code.
[self setBackgroundColor:[UIColor clearColor]];
}
return self;
}
// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
- (void)drawRect:(CGRect)rect {
/* Draw a circle */
// Get the contextRef
CGContextRef contextRef = UIGraphicsGetCurrentContext();
// Set the border width
CGContextSetLineWidth(contextRef, 1.0);
// Set the circle fill color to GREEN
CGContextSetRGBFillColor(contextRef, 100.0, 255.0, 0.0, 1.0);
// Set the cicle border color to BLUE
CGContextSetRGBStrokeColor(contextRef, 0.0, 0.0, 255.0, 1.0);
// Fill the circle with the fill color
CGContextFillRect(contextRef, CGRectMake(20, 0, rect.size.width, rect.size.height));
// Draw the circle border
//CGContextStrokeRectWithWidth(contextRef, rect, 10);//(contextRef, rect);
}
And this Custom View you can use as a background View for cell selection like this.
TestView *bgView = [[TestView alloc] initWithFrame:cell.frame]; // Creating a view for the background...this seems to be required.
cell.selectedBackgroundView = bgView;
May be this help you.
Thanks,
Minesh Purohit.
Does the cell have fixed size and highlight area ?
If yes, create an image and use image view as the selectedBackgroundView
Try to set frame size for selectionView where x = 20. I am not sure about this but I guess it should work for your given scenario.
I created a button, with a custom image and displayed it in a frame.
Now I'm trying to change the button's frame, inside an animation block.
Unfortunately, it doesn't seem to work - the frame doesn't change as expected.
I have written the following code:
UIButton *movingButton = [[UIButton buttonWithType:UIButtonTypeCustom] retain];
UIImage *image = [UIImage imageNamed:#"A_normal_image.png"];
[movingButton setImage:image forState:UIControlStateNormal];
movingButton.frame = CGRectMake(160, 240, 0, 0);
[movingButton addTarget:self action:#selector(moveButton:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:movingButton];
CGRect newFrame CGRectMake(20, 120, 44, 88);
[UIView animateWithDuration:0.5 animations:^{ movingButton.frame = newFrame; }];
[movingButton release];
Am I missing something? How should I do that then?
Thanks in advance,
Sagiftw
You should use floats instead of ints:
movingButton.frame = CGRectMake(160, 240, 0, 0);
to:
movingButton.frame = CGRectMake(160.0f, 240.0f, 0.0f, 0.0f);
I want to use an image of size 27x27 with the center 1 pixel stretchable as the backgroundImage of an UIButton. Here is my code:
[button setBackgroundImage:[UIImage imageNamed:#"button_image"] forState:UIControlStateNormal];
button.frame = CGRectMake(0.f, 0.f, 27.f, 27.f);
button.contentStretch = CGRectMake(13.f/27.f, 13.f/27.f, 1.f/27.f, 1.f/27.f);
[button setTitle:NSLocalizedString(#"long title", #"long title") forState:UIControlStateNormal];
[button sizeToFit];
CGRect buttonFrame = button.frame;
buttonFrame.size.width += 18.f * 2;
button.frame = buttonFrame;
But the result is no different from that without setting contentStretch at all.
So how to correctly use contentStretch to achieve what I want?
Please don't tell me again and again that I can achieve the same effect with stretchableImageWithLeftCapWidth:topCapHeight:. I know that and it's apparently not what I'm asking for. I just want to know how to properly use contentStretch. Thanks.
One issue I see is that you're dividing using integer division. 1 / 27 is equal to 0. 1.0 / 27.0 is equal to 0.037...
If all you want is a stretchable background on your button, check out stretchableImageWithLeftCapWidth:topCapHeight: on UIImage. Create the stretchable image that way, then set it to the background of your button.
I don't know the special behaviour with UIButtons (I'd also suggest to use stretchableImages there as it is a compound view). However, if you want to use contentStretch you could do so on an UIView given your data this was:
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0,0,100,100)];
view.layer.contents = (id)[[UIImage imageNamed:#"button_image"] CGImage];
view.contentStretch = CGRectMake(13./27., 13./27., 1./27., 1./27.);
This should be enough to have a UIView with a stretchable background.
Use -[UIImage stretchableImageWithLeftCapWidth:topCapHeight:].
I put this in the init method of a subclass of UIView:
// Add errorBackground & errorLabel.
rect.size.height = 26.0f;
errorBackground = [[UIImageView alloc] initWithFrame:rect];
errorBackground.image = [[UIImage imageNamed:#"ErrorBubble.png"]
stretchableImageWithLeftCapWidth:13 topCapHeight:0];
UILabel *errorLabel = [[UILabel alloc] initWithFrame:
CGRectMake(0.0f, 0.0f, rect.size.width, rect.size.height)];
errorLabel.autoresizingMask = UIViewAutoresizingFlexibleWidth;
errorLabel.backgroundColor = [UIColor clearColor];
errorLabel.textAlignment = UITextAlignmentCenter;
errorLabel.font = [UIFont systemFontOfSize:14.0f];
errorLabel.text = #"1 Failed Passcode Attempt";
errorLabel.textColor = [UIColor whiteColor];
errorLabel.shadowColor = [UIColor blackColor];
errorLabel.shadowOffset = CGSizeMake(0.0f, -1.0f);
[errorBackground addSubview:errorLabel];
[errorLabel release];
[self addSubview:errorBackground];
ErrorBubble.png:
ErrorBubble#2x.png:
Unsatisfying but simple answer:
You can't, until Apple fixes this. IMO it's a long outstanding and very annoying bug.
The UIButton implementation consists of a couple of subviews, and the (internal) background view does not seem to reflect the settings done on the UIButton view.