iOS using background in normal tableview - objective-c

I was wondering how I actually use background in normal tableview(non grouped). For example take a look at the clock app and the background there. Any ideas?

You can set the background of your table view using the same techniques as the grouped table view (something like self.tableView.backgroundView = anImageView;), but your cells' background are opaque and, therefore, will hide it.
You'll then have to set, in tableView:cellForRowAtIndexPath: the background color of your cells to clearColor [UIColor clearColor] and it's backgroundView to nil.
Run the app now, and there might still be something wrong: the background of the cell's labels is possibly also opaque (I say possibly because the cells might have picked up the cell background color and changed the background color of their subviews accordingly).
If it is the case, once again, in tableView:cellForRowAtIndexPath:, set the subviews's background color to clearColor.

You can also try to set image view with your own image as backgroundView:
UIImage *yourImage = ...
UIImageView *imageView = [[UIImageView alloc] initWithImage:yourImage];
self.tableView.backgroundView = imageView;
[imageView release];

Related

How do I stop view controllers from being clear color?

I have created a screen tutorial for my app.
I've done this by creating a PageViewController to manage 4 viewControllers.
In the PageViewController I have implemented the following code
self.modalPresentationStyle = UIModalPresentationFormSheet;
I have also set the alpha on the pageViewController view to .45
This makes the PageViewController transparent which is exactly what I want.
However, it is also making everything inside the 4 viewControllers that are being managed by the PageViewController transparent i.e. buttons, labels, etc.
How can I stop all of those object from being transparent?
Views always work like this. If you wanted to make a view semi-transparent, it would usually be pretty vexing if that didn't also affect all of its subviews. The times when you want your alpha setting to also affect the subviews likely far outnumber the times when you don't.
What you can do instead of making the view transparent is to make its background color transparent. That is, instead of:
self.view.backgroundColor = [UIColor blueColor];
self.view.alpha = 0.45;
you can do:
self.view.backgroundColor = [UIColor colorWithRed:0 green:0 blue:1 alpha:.45];
That way, your subviews are not affected, because while the alpha of your main view's background color is 0.45, the alpha of the view itself is still 1.0.
To change the background color of a view, use the following on the view:
[viewController.view setBackgroundColor:[UIColor COLOR]];
where COLOR is the color you would like (i.e. whiteColor)

Add background shadow to UIButton

How can add a light gray shadow to a UIButton, I don't want a method to do this at the moment, it should be something like:
UIButton *button1... button1.layer.shadowOpacity = 0.8
etc, but that doesn't work, it only adds a shadow inside the button, but I need it on the outside. Thanks!
First you have to #import <QuartzCore/QuartzCore.h>. Then:
mybtn.layer.shadowColor = [UIColor blackColor].CGColor;
mybtn.layer.shadowOpacity = 0.5;
mybtn.layer.shadowRadius = 2;
mybtn.layer.shadowOffset = CGSizeMake(3.0f,3.0f);
You can also use –[UIButton setBackgroundImage:forState:] to set the background image for UIControlStateNormal to one with a shadow. E.g.:
[button setBackgroundImage:[UIImage imageNamed:#"ButtonBackgroundNormal"]
forState:UIControlStateNormal];
where ButtonBackgroundNormal.png has a shadow. Images often render faster than drawing with code. And, speed is important, especially if you're adding it to a UITableViewCell. In that case, to speed up scrolling speed, make sure the background image is completely opaque by designing it with the same background color of the UITableViewCell and saving it without transparency. Then, set button.opaque = YES.

Draw Over Image

I'm working on some drawing code. I have that portion working great.
I want to draw over an image, but I want to still be able to see the detail of the image, the black lines, etc.
What I am working on is making a transparent UIImageView that holds the image.
I'm not sure how to get this set up properly though.
Should this be added above the other UIImageView that I color on or below it?
Here's what I have so far:
- (void)viewDidLoad
{
[super viewDidLoad];
topImageView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 46, 320, 370)];
[topImageView setImage:[UIImage imageNamed:#"imagesmall.png"]];
topImageView.alpha = 1.0;
topImageView.layer.opacity = 1.0;
topImageView.layer.opaque = NO;
[self.view addSubview:topImageView];
[topImageView release];
}
Thoughts anyone?
Yes, you can draw views over other views. They are drawn in the order that they're added as subviews, unless you reorder them after that.
You may need to set the opaque property for some views (this is distinct from and overrides their layer opacity), and set their backgroundColor to nil. UIImageView seems to be transparent by default, as long as its image is; some other UIView subclasses are not.
So, just what is your overlay going to be? If you just need to display one image over another, what you have here seems to work already. If you need to draw some lines programmatically, you'll need to do this:
Create a subclass of UIView.
Implement its drawRect method to display the content you need.
When you add your custom view on top of the background image, make sure it is not opaque and has no backgroundColor.
A common problem here is to find that your foreground is working, but the background isn't being loaded properly. To make sure the background is there, set the alpha of the foreground view to 0.5. You won't want to do that in production, but it will allow you to verify that both views exist.

UITableViewCell's backgroundView overlapping contentView

I am trying to set the backgroundView parameter of a UITableViewCell, but the backgroundView is overlapping the bounds of the cell. I have tried setting masksToBounds to YES, but that doesn't seem to make a difference. Please can you tell me where I am going wrong?
Here is an image showing my problem:
Here is my code:
UIImageView *iv = [[[UIImageView alloc] initWithFrame:cell.frame] autorelease];
[iv setImage:[UIImage imageNamed:#"paper"]];
[iv.layer setMasksToBounds:YES];
[cell.layer setMasksToBounds:YES];
[cell.contentView.layer setMasksToBounds:YES];
[cell setBackgroundView:iv];
Using masksToBounds doesn't work because the bounds of the cell are a rectangle.
Even if the corners of the cell are rounded, they're still part of the cell (but they contain transparent pixels). When a cell is displayed in a grouped table view, its background view (and its selected background view) is drawn in regard of its position in its section (middle, top, bottom, single).
So, if you want to provide a custom background view, you need to compute the position of the cell in its section and provide the adequate background :
either by using 4 different images
or by using the mask property of the background image's layer
or by subclassing UIView and implementing drawRect: so the graphic context is clipped before the image is drawn.
Are you setting every cell that background view, if so why don't you just set it to the table view background.

Background image for list view still shows white behind text for cells

I wanted to put a background image partially visible behind a list view. I created a list view in my nib with an image view behind it and made the list view background 20% opacity. This allows the background image to show thru but my text in the cells show a white background behind and if I create the cells in cellForRowAtIndexPath the cells have a white background too.
I am creating and setting the cell textLabel and the detailTextLabel in the cellForRowAtIndexPath event.
Not sure how to get rid of that, or if there is a better way to do the background image.
I had a similar issue and resolved it by setting the cell.contentView.backgroundColor to [UIColor clearColor] in cellForRowAtIndexPath.
If you did not want to make the whole cell transparent but the labels only, you can set the backgroundColor attribute of the textLabel and detailTextLabel to clear as well:
cell.textLabel.backgroundColor = [UIColor clearColor];
To set the background image of a table at run time rather than in a nib you can create a new UIColor from an image. Like so:
UIImage *img = [UIImage imageWithContentsOfFile: someFilePath]; // get your background image
UIColor *backgroundColor = [[UIColor alloc] initWithPatternImage: img];
[myTable setBackgroundColor: backgroundColor];
[backgroundColor release];