I'm new to Xcode. This is probably a very simple question to you, but I wonder if anyone can help me.
What I want to do is to load an image in a customised UIImageView, when clicking the image, the imageview will change to another image. When I run the simulator, there are no error messages, but the second image does not load after clicking.
I've declared a UIImageView subclass dragView. In the dragView.m, I have such codes:
-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
[self changePicture];
}
-(void) changePicture {
NSString *path = [[NSHomeDirectory() stringByAppendingPathComponent:#"Documents"] stringByAppendingPathComponent:#"Red Flower.png"];
self.image = [UIImage imageWithContentsOfFile:path];
}
By the way, I have enabled the interaction. Many thanks!
You probably need to tell the OS to update the view by calling [self setNeedsDisplay:YES].
Related
I have presented UIImagePickerController from modally presented view controller. After clicking the image I get a black image instead of the clicked picture
I did something Like this.
//From ViewController1 I presented view controller2 with
- (IBAction)buttontappedToPresentViewController2:(id)sender
{
ViewController2* controller2 = [[ViewController2 alloc] initWithNibName:#"ViewController2" bundle:nil];
controller2.modalPresentationStyle = UIModalPresentationPageSheet;
[self controller2 animated:YES completion:nil];
}
//In ViewController2, I presented the UIIMagePickerController
- (IBAction)cameraButtonTapped:(id)sender
{
UIImagePickerController *cameraController = [[UIImagePickerController alloc] init];
cameraController.mediaTypes = #[(NSString *)kUTTypeImage,(NSString*)kUTTypeMovie];
cameraController.sourceType = UIImagePickerControllerSourceTypeCamera;
[self presentViewController:cameraController animated:YES completion:NULL];
}
After clicking the image you will get black screen instead of the captured image with retake and use photo options. If you select "Use Photo" option you get the correct image in callback.
Note: If you do not set UIModalPresentationStyle for viewController2, the code works fine.
Any idea what is going wrong here.
EDIT: I have used XCODE 5.1 and my target deployment is iOS 7. I am running the app on iOS8 device.
I have sub-classed uiscrollview and used initWithCoder to prepare my uiscrollview with all the subviews. I have used below code to set it up:
- (id)initWithCoder:(NSCoder *)aDecoder {
if ((self = [super initWithCoder:aDecoder])) {
NSLog(#"%f", self.frame.size.height);
self.contentSize = CGSizeMake(5000, self.frame.size.height);
labelContainerView = [[UIView alloc] init];
labelContainerView.frame = CGRectMake(0, 0, self.contentSize.width, self.contentSize.height/2);
labelContainerView.backgroundColor = [UIColor yellowColor];
[self addSubview:labelContainerView];
}
But this keeps failing because the self.frame property always return 0 values. Its super important for me to use self.frame property because I want to use storyboard to do any height adjustments for the frame of the scrollview.
I have tried the same thing using xib files instead of using the storyboard and it works fine. But in my project I dont want to use xib files.
It'll be really great if anyone can explain me why I get 0 values in initWithCoder: method when I use storyboard? and if using storyboard how to achieve this?
PS: I notice layoutSubviews method return correct frame information but I cannot create my subviews here since it get called for each frame change (when I scroll)
Are you using Autolayout in your Storyboard?
If you are really not taking advantage of it, you can disable it and your -initWithCoder: method will return your frame again.
If you do need Autolayout, try the following:
-(void)awakeFromNib
{
[super awakeFromNib];
[self setNeedsLayout];
[self layoutIfNeeded];
// self.frame will now return something :)
}
I want to create NSTextField programmatically. I am new to Mac App Development.
Can anyone help me in this ?
Update :
I tried this code
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
NSView *myView = [[NSView alloc] init];
NSRect frameRect = NSMakeRect(20,20,100,140);
NSTextField *myTextField = [[NSTextField alloc] initWithFrame:frameRect];
[myView addSubview:myTextField];
}
This does nothing. Please correct me if i'm wrong anywhere.
Thank you.
Creating UI elements programmatically is very simple in Cocoa.
It involves two steps:
Create the view and set a frame to it.
Add it as a subview to any super view.
Following snippet will you help you understand better.
NSRect frameRect = NSMakeRect(20,20,40,40); // This will change based on the size you need
NSTextField *myTextField = [[NSTextField alloc] initWithFrame:frameRect];
[myView addSubview:myTextField];
It looks like you're creating an NSTextField OK, but you're not adding it to anywhere visible in the view hierarchy. Your app probably contains one or more NSWindow instances; if you want a view to appear in a particular window, you should add it as a subview of that window's content view.
I have a detail view, and when viewdidload in detailviewcontroller, MPMoviePlayerController allocs and plays an audio, but even if I navigate backto main table, audio is still being played.
How can I stop MPMovieplayercontroller when I navigate back to main table ? This is my MPMoviePlayerController code:
.h
MPMoviePlayerController *player;
.m
- (void)viewDidLoad
{
[super viewDidLoad];
//Get the Movie
NSURL *movieURL = [NSURL URLWithString:#"some link"];
player = [[MPMoviePlayerController alloc] initWithContentURL:movieURL];
//Place it in subview, else it won’t work
player.view.frame = CGRectMake(20, 20, 280, 25);
player.backgroundView.backgroundColor = [UIColor clearColor];
[self.view addSubview:player.view];
// Play the movie.
[player play];
}
I even added following code into viewdidunload method, but didn't work.
- (void)viewDidUnload {
[player stop];
player.initialPlaybackTime = -1;
[player release];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}
What do you guys suggest ?
Thanks in advance,
I liked the user experience of viewDidDisappear better than viewWillDisappear. The animation starts and the movie stops after - the audio flows better for me this way.
-(void)viewDidDisappear:(BOOL)animated {
[super viewDidDisappear:animated];
[_moviePlayer stop];
}
I am having a similar issue. I am unable to use "viewDidDisappear" or "viewWillDisappear" because I have a "config" type view that can be opened while the content is playing, and it will trigger those two methods.
EDIT: Found that viewDidUnload and viewWillUnload are not getting called any more (I'm currently on an iOS 6+ device)...
From the documentation:
Availability: iOS (3.0 and later) Deprecated: Views are no longer
purged under low-memory conditions and so this method is never called.
I just created a simple function called unload, and inside the function, set any objects I needed to = nil (I'm using ARC). At the time that I make the call to remove the view, I call the unload function as well. Hope it helps someone.
I want to make transparent NSTableView.
I am using WindowController class here.
I was trying this:
- (void)windowDidLoad
{
[super windowDidLoad];
[[self enclosingScrollView] setDrawsBackground: NO];
[[self enclosingScrollView] setBorderType:NSNoBorder];
}
- (BOOL)isOpaque {
return NO;
}
- (void)drawRect:(NSRect)drawRect
{
[super drawRect: drawRect];
}
But when i was writing this code i can't found enclosingScrollView in help window.
you can see here..
Any help?? Please remember me or correct me if i am doing something wrong.
Thank you.
If you have an NSScrollView enclosing your NSTableView, you can set the scroll view's drawsBackground property to NO like this:
yourScrollView.drawsBackground = NO;
Got Answer..!!! I just tried this
[tableview setBackgroundColor:[NSColor clearColor]];
[tableview setHeaderView:nil];
and its working fine.. – – Snehal
Copied from comment in question, as its a bit buried...
If your app needs to display a transparent table view, set the background color of the table view to be clear and set the enclosing scroll view to not draw its background. The following code snippet shows one way to display a transparent table:
Swift:
yourTableView.backgroundColor = NSColor.clear
yourTableView.enclosingScrollView?.drawsBackground = false
Objective-C
[theTableView setBackgroundColor:[NSColor clearColor];
[[theTableView enclosingScrollView] setDrawsBackground:NO];
Apple - Modifying a Table’s Visual Attributes