I am trying to create a UIButton programmatically instead of using the interface builder. I initialize and set the button frame but the button doesn't seem to appear on the view. My code is as follows:
UIButton *showInfoButton = [[UIButton alloc] init];
CGRect buttonFrame = CGRectMake(0,0, 150, 150);
showInfoButton.frame = buttonFrame;
What am I missing? Please bear with me as I am new to iOS.
You forgot to add your UIButton as a subview to the UIView you want it to display on. Since you are building UI programmatically, you need to manually add the button as a subview to the container view.
You can do so by using this line of code:
[self.view addSubview:showInfoButton];
The button might not still appear as you are making a custom button which has a transparent background colour. In order to see the button, you can set the UIButton's backgroundColor property as follows:
[showInfoButton setBackgroundColor:[UIColor blackColor]];
Related
In app my, if you tap on a certain area a UIPopoverController appears with UIButtons that perform certain tasks when clicked. The UIButtons (called CableDisconnectButton) are a subclassed UIButton so I could add two additional properties to them. I also add UILabels to go over the buttons
However, the background images of the buttons are invisible or don't appear until I tap on the screen somewhere. The UIlabels show up fine, but not the buttons. It can be a tap on the UIPopoverController or anywhere else on the screen. Once I've tapped that first time, the buttons will be there until the app is closed. So, this only happens right after launch and up until I first open that UIPopover. I tap plenty of times before opening the popover.
The functionality of the buttons and everything else works fine, but the background images are hidden on that first launch and I have no idea why.
Here's how I create the buttons and UILabel:
//create custom button
CableDisconnectButton *removeConnectionButton = [CableDisconnectButton buttonWithType:UIButtonTypeCustom];
removeConnectionButton.frame = CGRectMake(x, y, 190, 80);
removeConnectionButton.backgroundColor = [UIColor clearColor];
[removeConnectionButton setBackgroundImage:[UIImage imageNamed:#"images/cable_disconnect_button.png"] forState:UIControlStateNormal];
[removeConnectionButton setBackgroundImage:[UIImage imageNamed:#"images/cable_disconnect_button_over.png"] forState:UIControlStateHighlighted];
//set input and output jacks to button properties
removeConnectionButton.inputJack = inputJack;
removeConnectionButton.outputJack = self.outputJackView;
//add action to button
[removeConnectionButton addTarget:self action:#selector(removeConnectionButtonTarget:) forControlEvents:UIControlEventTouchUpInside];
//create label for output
UILabel *outputConnectionLabel = [[UILabel alloc] initWithFrame:CGRectMake(x+18, y+5, 180, 22)];
outputConnectionLabel.backgroundColor = [UIColor clearColor];
outputConnectionLabel.textColor = [UIColor whiteColor];
outputConnectionLabel.text = self.outputJackView.jackDisplayName;
outputConnectionLabel.font = [UIFont systemFontOfSize:16];
//add subviews
[self addSubview:removeConnectionButton];
[self addSubview:outputConnectionLabel];
I've tried to add a regular, non-custom UIButton and it appears without the tap. I suspect it may have something to do with the subclassed UIButton, but I'm not sure why. The extra properties added to the UIButton are strings that are crucial to the functionality of the and can't be omitted.
After beating my head off the desk for days, I ran into the "Clean Build Folder" option. I've cleaned the project plenty of times, but wasn't aware of "Clean Build Folder". To execute this, simple hold the Option key, click Product from the menu and select Clean Build Folder.
So, if your app isn't behaving the way it should and it makes no sense AT ALL, try this.
I have a button in a tableView Cell that I need to respond to touch events. Normally this would easily be solved by
[cell.playButton addTarget:self action:#selector(playButtonPressed:) forControlEvents:UIControlEventTouchUpInside];
inside of -tableView:cellForRowAtIndexPath:
The problem I am having is that my button is inside of a custom UITableViewCell subclass and is also the subview of a view that I am creating inside of that class..
for example:
UIView *view = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 320, 44)];
self.theView = view;
[self addSubview:view];
[view release];
UIButton *playButton = [UIButton buttonWithType:UIButtonTypeCustom];
playButton.frame = CGRectMake(5, 5, 100, 30);
[playButton setImage:[UIImage imageNamed:#"button_playvid.png"] forState:UIControlStateNormal];
[playButton setImage:[UIImage imageNamed:#"button_playvid_active.png"] forState:UIControlStateHighlighted];
self.playButton = playButton;
[self.theView addSubview:playButton];
When the button is a subview of a view that I create within the custom UITableViewCell then the cell is highlighted instead of the button being pressed so the target that I setup in -tableView:cellForRowAtIndexPath is never called. Not sure why.. any help?
Thanks,
Joel
PS. I realize that there probably isn't a practical reason to create a background view exactly like this since there already is one. This is just example code that I'm using to explain a problem I'm having.. :D
Thanks for Looking!
The UIView you are adding is actually a UIImageView. From the docs:
New image view objects are configured to disregard user events by default. If you want to handle events in a custom subclass of UIImageView, you must explicitly change the value of the userInteractionEnabled property to YES after initializing the object.
I think that either userInteractionEnabled cascades to subviews or the superview will not pass the touch to its subviews in this case, so your button will not be receiving touches. Set your image view to have .userInteractionEnabled = YES and you should be fine.
I had the same problem and tried EVERYTHING. The thing that finally did it was implementing the method
(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
Just return whatever the height is of your custom cell (look in the NIB file)
Recently I've ran into such issue with legacy code. The reason was that earlier we used to add subviews to custom UITableViewCell instance itself and now we have to add to contentView of the cell instance.
I fixed it by changing:
addSubview(increaseButton)
to
contentView.addSubview(increaseButton)
Of course, isUserInteractionEnabled should be true.
Instead of button, you could try the same with an image. You could define which method to be called when the image is clicked.
I'm trying to create a UIBarButtonItem that looks like the "list" button on the iPod.app
so I have 2 questions:
How can I set the icon to look like the iPod's one? I saw it in other apps, but couldn't find it on xcode. (the icon that appears on the right side of the navigation bar on the "now playing" screen)
how can I set the UIBarButtonItem's image to show without it's default border?
Try adding custom view with button you want as a subview to your bar;
UIView* myView = [[UIView alloc] initWithFrame:myBar.bounds];
UIbutton* myBtn = [[UIButton alloc] initWithFrame:CGRectMake(x,y,width,height)];
[myBtn setImage:myImage forState:UIControlStateNormal];
[myView addSubview:myBtn];
[myBar addSubview:myView];
I have a idea to hide some keys in keyboard. I use the exact background of the keyboard and use it above the keyboard.
So I create a textView and add a accessoryView
//Create the view
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, -10, 768, 300)];
[view setBackgroundColor:[UIColor greenColor]]
UITextField text = [[UITextField alloc] initWithFrame:CGRectMake(120, 10, 80, 28)];
[text setKeyboardType:UIKeyboardTypeNumbersAndPunctuation];
[text setInputAccessoryView:view];
This really hide the keyboard, but if I click in this view, the button still show. I try to use a UIButton, but the button don't catch the click. And I try becameFirstResponder when UIKeyboardDidShowNotification and no success.
Any Ideas?
You can set userInteractionEnabled to YES for your accessory view. This will make your view swallow all the touches.
If you want a custom view for editing, though, you can do this by setting a specific editing view for your field rather than trying to put something else on top of the keyboard.
i found a lot of topics around placing buttons on navigation bar but none showed me how to place a button at the center of the bar.
I found an example with a segmented control but i don't need that.
Just a button instead of the title. Is that possible? ;-)
Edit:
That will do it:
UIButton *titleButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[titleButton setFrame:CGRectMake(0, 0, 170, 35)];
self.navigationItem.titleView = titleButton;
You can set any custom view (e.g. UIButton) as a titleView property to your current navigationItem - that should do the trick.