i have a problem in UIImageView's animating - iphone

-(IBAction) change {
self.imageView.animationImages = myImages;
self.imageView.animationDuration = 2;
if(self.imageView.isAnimating == NO){
[self.imageView startAnimating];
NSLog(#"if bool = %d", self.imageView.isAnimating);
}
else {
self.imageView stopAnimating];
NSLog(#"else bool = %d", self.imageView.isAnimating);
}
}
hello, i'm studying iOS programming.
but i have a question.
i have a button and when i click the button, then this method will be called.
first i click the button, then this code will start the if statement. that's what i want.
i click the button again, i think that will execute the else statement.
but it always execute the if statement only.
why is that?
i really don't know why is that. please help me

I think setting the properties like animationImages or animationDuration will stop the animation, so that by clicking, you every time stop and then just after (re)start it in the if part. Try setting these two properties outside the action method you wrote, and just let the if/else sequence.
-(IBAction) change {
// set these two anywhere else
//self.imageView.animationImages = myImages;
//self.imageView.animationDuration = 2;
if(self.imageView.isAnimating == NO){
[self.imageView startAnimating];
NSLog(#"if bool = %d", self.imageView.isAnimating);
}
else {
self.imageView stopAnimating];
NSLog(#"else bool = %d", self.imageView.isAnimating);
}
}

Related

Trying to toggle a view on/off using tags

I am trying to toggle a view on and off which works, but what i need to know is if I am abusing tags with this method. If so is there a better way?
- (IBAction) myButton:(UIButton*)sender {
if ([myLabelText.text isEqualToString:#""])
{
// do nothing
} else {
if ( sender.tag )
{
sender.tag = 0;
[[self firstView] setHidden:YES];
} else {
sender.tag = 1;
firstView.alpha = 100;
[[self firstView] setHidden:NO];
}
}
}
You can use the tag property for anything you like, but in this case you can toggle the visibility without using it:
[self firstView].hidden = ![self firstView].hidden;
Also, the valid range for UIView's alpha property is from 0.0 to 1.0. I'm not sure what you're trying to do there.

Hiding or moving SegmentContoller

Hello I've tried for 3 weeks to solve this issue and it stumps me. What i am trying to do is create a 3 part segment from an array, display it in a view in a certain position, then remove it from view when the "OFF" flag is set. Every thing works except the removal of the segment. It will even commuticate with (pickOne) and display the segment letters in a label. What i can't get to work is either of the two: setHidden:YES, or removeAllSegments. Any help would be appreciated. Here is my code.
- (void) showSegment {
int x = 192;
int y = 212;
int w = 125;
int h = 25;
SegUnit1 = #"A";
SegUnit2 = #"B";
SegUnit3 = #"C";
threeSegs = [NSArray arrayWithObjects: SegUnit1, SegUnit2, SegUnit3, nil];
segSize = [NSArray arrayWithArray:threeSegs];
UISegmentedControl *heightSC = [[UISegmentedControl alloc] initWithItems:segSize];
if ([segmentState_height isEqualToString:#"ON"]) {
NSLog(#"segmentState_height = %#",segmentState_height);
heightSC.frame = CGRectMake(x, y, w, h);
heightSC.segmentedControlStyle = UISegmentedControlStyleBar;
heightSC.selectedSegmentIndex = -1;
[heightSC addTarget:self
action:#selector(pickOne:)
forControlEvents:UIControlEventValueChanged];
[self.view addSubview:heightSC];
[heightSC release];
} else if ([segmentState_height isEqualToString:#"OFF"]) {
NSLog(#"segmentState_height = %#",segmentState_height);
[heightSC setHidden:YES]; // NSLog showing "OFF" but segment will not hide.
[heightSC removeAllSegments]; // NSLog showing "OFF" and segment is suppose to dismantle and does not.
}
}
I know now that i have to "not" create and remove in the same function, and was given a tip on correcting this but I don't know how to use the tip.
here is what was suggested.
Well, your method is a little confused, since you are trying to both create and hide at the same time. So you might consider splitting that up into separate methods.
In general, it will be along these lines:
Code:
if ([self theControlProperty] == nil)
{
UISeg... *theControl = [[UISeg alloc] ....];
[self setTheControlProperty:theControl];
...
}
if (shouldHideTheControl)
{
[[self theControlProperty] setHidden:YES];
}
Any help would be appreciated.
The problem you have is that you're creating a new UISegmentedControl instance every time that method is called. The first time through, you create an instance and add it as a subview to your view. This apparently works fine, as it should. Then the method returns, and you no longer have any easy way to refer to that instance that you created. When you re-enter -showSegment, you create a different instance, and then hide and/or destroy it. This different instance has no effect whatsoever on the instance that you gave to the view.
What you need to do is make heightSC an instance variable. Add it to the interface declaration in the header file, then initialize it only once, and hide or modify it as needed subsequently. The key point is that you need to have a reference to the instance of the UISegmentedControl which is being drawn on the screen, a reference that lives outside the method itself that you can use the second, third, fourth, etc time you call that method.
Try using the remove segments in your button choice method pickOne. This takes it outside the showSegment method and matches the users desired action to make the change and clear off the buttons.
- (void) pickOne:(id)sender {
UISegmentedControl* userChose = sender;
if( [userChose selectedSegmentIndex] == 0 ){
your first button operation;
[heightSC removeAllSegments];
}
if( [userChose selectedSegmentIndex] == 1 ){
your second button operation;
[heightSC removeAllSegments];
}
if( [userChose selectedSegmentIndex] == 2 ){
your third button operation;
[heightSC removeAllSegments];
}
}
I tried this and got the results I was looking for. Thanks goes to Mythogen and BrianSlick I just need to check and make sure there are no leaks. Now that will be a task.
Does anyone know if I need the second [heightSC release]; ?
// .h
# interface ------ {
UISegmentedControl *segmentPicked;
}
|
#property (nonatomic, retain) UISegmentedControl *segmentPicked;
// .m
|
#synthesize segmentPicked;
|
if ([self segmentPicked] == nil) {
UISegmentedControl *heightSC = [[UISegmentedControl alloc] initWithItems:segSize];
[self setSegmentPicked:heightSC];
[heightSC release];
heightSC.frame = CGRectMake(x, y, w, h);
heightSC.segmentedControlStyle = UISegmentedControlStyleBar;
heightSC.selectedSegmentIndex = -1;
[heightSC addTarget:self
action:#selector(pickOne:)
forControlEvents:UIControlEventValueChanged];
[self.view addSubview:heightSC];
[heightSC release];
}
if ([segmentState_height isEqualToString:#"OFF"])
{
[[self segmentPicked] setHidden:YES];
} else {
[[self segmentPicked] setHidden:NO];
}
[yourSegment removeFromSuperview];
?

UIWebView - Enabling Action Sheets on <img> tags

Is it just me or has the action sheet on <img> tags been disabled in UIWebView? In Safari, e.g, when you want to save an image locally, you touch and hold on the image to get an action sheet shown. But it's not working in my custom UIWebView. I mean, it is still working for <a> tags, i.e, when I touch and hold on html links, an action sheet shows up. But not for the <img> tags.
I've tried things like putting img { -webkit-touch-callout: inherit; } in css, which didn't work. On the other hand, when I double-tap and hold on the images, a copy-balloon shows up.
So the question is, has the default action sheet callout for <img> tags been disabled for UIWebView? Is so, is there a way to re-enable it? I've googled around and saw many Q&As on how to disable it in UIWebView, so is it just me who aren't seeing the popup?
Thanks in advance!
Yes apple has disabled this feature (among others) in UIWebViews and kept it for Safari only.
However you can recreate this yourself by extending this tutorial, http://www.icab.de/blog/2010/07/11/customize-the-contextual-menu-of-uiwebview/.
Once you've finished this tutorial you'll want to add a few extra's so you can actually save images (which the tutorial doesn't cover).
I added an extra notification called #"tapAndHoldShortNotification" after 0.3 seconds which calls a method with just the disable callout code in it (to prevent both the default and your own menu popping while the page is still loading, a little bug fix).
Also to detect images you'll need to extend the JSTools.js, here's mine with the extra functions.
function MyAppGetHTMLElementsAtPoint(x,y) {
var tags = ",";
var e = document.elementFromPoint(x,y);
while (e) {
if (e.tagName) {
tags += e.tagName + ',';
}
e = e.parentNode;
}
return tags;
}
function MyAppGetLinkSRCAtPoint(x,y) {
var tags = "";
var e = document.elementFromPoint(x,y);
while (e) {
if (e.src) {
tags += e.src;
break;
}
e = e.parentNode;
}
return tags;
}
function MyAppGetLinkHREFAtPoint(x,y) {
var tags = "";
var e = document.elementFromPoint(x,y);
while (e) {
if (e.href) {
tags += e.href;
break;
}
e = e.parentNode;
}
return tags;
}
Now you can detect the user clicking on images and actually find out the images url they are clicking on, but we need to change the -(void)openContextualMenuAtPoint: method to provide extra options.
Again here's mine (I tried to copy Safari's behaviour for this):
- (void)openContextualMenuAt:(CGPoint)pt{
// Load the JavaScript code from the Resources and inject it into the web page
NSString *path = [[NSBundle mainBundle] pathForResource:#"JSTools" ofType:#"js"];
NSString *jsCode = [NSString stringWithContentsOfFile:path encoding:NSUTF8StringEncoding error:nil];
[webView stringByEvaluatingJavaScriptFromString:jsCode];
// get the Tags at the touch location
NSString *tags = [webView stringByEvaluatingJavaScriptFromString:
[NSString stringWithFormat:#"MyAppGetHTMLElementsAtPoint(%i,%i);",(NSInteger)pt.x,(NSInteger)pt.y]];
NSString *tagsHREF = [webView stringByEvaluatingJavaScriptFromString:
[NSString stringWithFormat:#"MyAppGetLinkHREFAtPoint(%i,%i);",(NSInteger)pt.x,(NSInteger)pt.y]];
NSString *tagsSRC = [webView stringByEvaluatingJavaScriptFromString:
[NSString stringWithFormat:#"MyAppGetLinkSRCAtPoint(%i,%i);",(NSInteger)pt.x,(NSInteger)pt.y]];
UIActionSheet *sheet = [[UIActionSheet alloc] initWithTitle:nil delegate:self cancelButtonTitle:nil destructiveButtonTitle:nil otherButtonTitles:nil];
selectedLinkURL = #"";
selectedImageURL = #"";
// If an image was touched, add image-related buttons.
if ([tags rangeOfString:#",IMG,"].location != NSNotFound) {
selectedImageURL = tagsSRC;
if (sheet.title == nil) {
sheet.title = tagsSRC;
}
[sheet addButtonWithTitle:#"Save Image"];
[sheet addButtonWithTitle:#"Copy Image"];
}
// If a link is pressed add image buttons.
if ([tags rangeOfString:#",A,"].location != NSNotFound){
selectedLinkURL = tagsHREF;
sheet.title = tagsHREF;
[sheet addButtonWithTitle:#"Open"];
[sheet addButtonWithTitle:#"Copy"];
}
if (sheet.numberOfButtons > 0) {
[sheet addButtonWithTitle:#"Cancel"];
sheet.cancelButtonIndex = (sheet.numberOfButtons-1);
[sheet showInView:webView];
}
[selectedLinkURL retain];
[selectedImageURL retain];
[sheet release];
}
(NOTES: selectedLinkURL and selectedImageURL are declared in the .h file to let them be accessed throughout the class, for saving or opening the link latter.
So far we've just been going back over the tutorials code making changes but now we will move into what the tutorial doesn't cover (it stops before actually mentioning how to handle saving the images or opening the links).
To handle the users choice we now need to add the actionSheet:clickedButtonAtIndex: method.
-(void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex{
if ([[actionSheet buttonTitleAtIndex:buttonIndex] isEqualToString:#"Open"]){
[webView loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:selectedLinkURL]]];
}
else if ([[actionSheet buttonTitleAtIndex:buttonIndex] isEqualToString:#"Copy"]){
[[UIPasteboard generalPasteboard] setString:selectedLinkURL];
}
else if ([[actionSheet buttonTitleAtIndex:buttonIndex] isEqualToString:#"Copy Image"]){
[[UIPasteboard generalPasteboard] setString:selectedImageURL];
}
else if ([[actionSheet buttonTitleAtIndex:buttonIndex] isEqualToString:#"Save Image"]){
NSOperationQueue *queue = [NSOperationQueue new];
NSInvocationOperation *operation = [[NSInvocationOperation alloc] initWithTarget:self selector:#selector(saveImageURL:) object:selectedImageURL];
[queue addOperation:operation];
[operation release];
}
}
This checks what the user wants to do and handles /most/ of them, only the "save image" operation needs another method to handle that. For the progress I used MBProgressHub.
Add an MBProgressHUB *progressHud; to the interface declaration in the .h and set it up in the init method (of whatever class you're handling the webview from).
progressHud = [[MBProgressHUD alloc] initWithView:self.view];
progressHud.customView = [[[UIImageView alloc] initWithImage:[UIImage imageNamed:#"Tick.png"]] autorelease];
progressHud.opacity = 0.8;
[self.view addSubview:progressHud];
[progressHud hide:NO];
progressHud.userInteractionEnabled = NO;
And the -(void)saveImageURL:(NSString*)url; method will actually save it to the image library.
(A better way would be to do the download through an NSURLRequest and update the progress hud in MBProgressHUDModeDeterminate to deflect how long it'll actually take to download, but this is a more hacked together implementation then that)
-(void)saveImageURL:(NSString*)url{
[self performSelectorOnMainThread:#selector(showStartSaveAlert) withObject:nil waitUntilDone:YES];
UIImageWriteToSavedPhotosAlbum([UIImage imageWithData:[NSData dataWithContentsOfURL:[NSURL URLWithString:url]]], nil, nil, nil);
[self performSelectorOnMainThread:#selector(showFinishedSaveAlert) withObject:nil waitUntilDone:YES];
}
-(void)showStartSaveAlert{
progressHud.mode = MBProgressHUDModeIndeterminate;
progressHud.labelText = #"Saving Image...";
[progressHud show:YES];
}
-(void)showFinishedSaveAlert{
// Set custom view mode
progressHud.mode = MBProgressHUDModeCustomView;
progressHud.labelText = #"Completed";
[progressHud performSelector:#selector(hide:) withObject:[NSNumber numberWithBool:YES] afterDelay:0.5];
}
And of cause add [progressHud release]; to the dealloc method.
Hopefully this shows you how to add some of the options to a webView that apple left out.
Of cause though you can add more things to this like a "Read Later" option for instapaper or a "Open In Safari" button.
(looking at the length of this post I'm seeing why the original tutorial left out the finial implementation details)
Edit: (updated with more info)
I was asked about the detail I glossed over at the top, the #"tapAndHoldShortNotification", so this is clarifying it.
This is my UIWindow subclass, it adds the second notification to cancel the default selection menu (this is because when I tried the tutorial it showed both menus).
- (void)tapAndHoldAction:(NSTimer*)timer {
contextualMenuTimer = nil;
UIView* clickedView = [self hitTest:CGPointMake(tapLocation.x, tapLocation.y) withEvent:nil];
while (clickedView != nil) {
if ([clickedView isKindOfClass:[UIWebView class]]) {
break;
}
clickedView = clickedView.superview;
}
if (clickedView) {
NSDictionary *coord = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithFloat:tapLocation.x],#"x",
[NSNumber numberWithFloat:tapLocation.y],#"y",nil];
[[NSNotificationCenter defaultCenter] postNotificationName:#"TapAndHoldNotification" object:coord];
}
}
- (void)tapAndHoldActionShort:(NSTimer*)timer {
UIView* clickedView = [self hitTest:CGPointMake(tapLocation.x, tapLocation.y) withEvent:nil];
while (clickedView != nil) {
if ([clickedView isKindOfClass:[UIWebView class]]) {
break;
}
clickedView = clickedView.superview;
}
if (clickedView) {
NSDictionary *coord = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithFloat:tapLocation.x],#"x",
[NSNumber numberWithFloat:tapLocation.y],#"y",nil];
[[NSNotificationCenter defaultCenter] postNotificationName:#"TapAndHoldShortNotification" object:coord];
}
}
- (void)sendEvent:(UIEvent *)event {
NSSet *touches = [event touchesForWindow:self];
[touches retain];
[super sendEvent:event]; // Call super to make sure the event is processed as usual
if ([touches count] == 1) { // We're only interested in one-finger events
UITouch *touch = [touches anyObject];
switch ([touch phase]) {
case UITouchPhaseBegan: // A finger touched the screen
tapLocation = [touch locationInView:self];
[contextualMenuTimer invalidate];
contextualMenuTimer = [NSTimer scheduledTimerWithTimeInterval:0.8 target:self selector:#selector(tapAndHoldAction:) userInfo:nil repeats:NO];
NSTimer *myTimer;
myTimer = [NSTimer scheduledTimerWithTimeInterval:0.2 target:self selector:#selector(tapAndHoldActionShort:) userInfo:nil repeats:NO];
break;
case UITouchPhaseEnded:
case UITouchPhaseMoved:
case UITouchPhaseCancelled:
[contextualMenuTimer invalidate];
contextualMenuTimer = nil;
break;
}
} else { // Multiple fingers are touching the screen
[contextualMenuTimer invalidate];
contextualMenuTimer = nil;
}
[touches release];
}
The notification is then handled like this:
// in -viewDidLoad
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(stopSelection:) name:#"TapAndHoldShortNotification" object:nil];
- (void)stopSelection:(NSNotification*)notification{
[webView stringByEvaluatingJavaScriptFromString:#"document.documentElement.style.webkitTouchCallout='none';"];
}
It's only a little change but it fixes the annoying little bug where you get 2 menus appear (the standard one and yours).
Also you could easily add iPad support by sending the touches location as the notification fires and then showing the UIActionSheet from that point, though this was written before the iPad so doesn't include support for that.
After struggling for, like 2 or 3 days non-stop on this problem, it seems like the position is computed "relatively" to the UIWebView's "TOP-LEFT" corner (I am programing for iOS 7).
So, to make this work, when you get the position, on the controller where your WebView is (i'll put a snippet of my code below), don't add the "scroll-offset"
SNIPPET - ContextualMenuAction:
- (void)contextualMenuAction:(NSNotification*)notification {
// Load javascript
[self loadJavascript];
// Initialize the coordinates
CGPoint pt;
pt.x = [[[notification object] objectForKey:#"x"] floatValue];
pt.y = [[[notification object] objectForKey:#"y"] floatValue];
// Convert point from window to view coordinate system
pt = [self.WebView convertPoint:pt fromView:nil];
// Get PAGE and UIWEBVIEW dimensions
CGSize pageDimensions = [self.WebView documentSize];
CGSize webviewDimensions = self.WebView.frame.size;
/***** If the page is in MOBILE version *****/
if (webviewDimensions.width == pageDimensions.width) {
}
/***** If the page is in DESKTOP version *****/
else {
// convert point from view to HTML coordinate system
CGSize viewSize = [self.WebView frame].size;
// Contiens la portion de la page visible depuis la webview (en fonction du zoom)
CGSize windowSize = [self.WebView windowSize];
CGFloat factor = windowSize.width / viewSize.width;
CGFloat factorHeight = windowSize.height / viewSize.height;
NSLog(#"factor: %f", factor);
pt.x = pt.x * factor; // ** logically, we would add the offset **
pt.y = pt.y * factorHeight; // ** logically, we would add the offset **
}
NSLog(#"x: %f and y: %f", pt.x, pt.y);
NSLog(#"WINDOW: width: %f height: %f", [self.WebView windowSize].width, [self.WebView windowSize].height);
NSLog(#"DOCUMENT: width: %f height: %f", pageDimensions.width, pageDimensions.height);
[self openContextualMenuAt:pt];
}
SNIPPET - in openContextualMenuAt:
To load the correct JS function:
- (void)openContextualMenuAt:(CGPoint)pt {
// Load javascript
[self loadJavascript];
// get the Tags at the touch location
NSString *tags = [self.WebView stringByEvaluatingJavaScriptFromString:[NSString stringWithFormat:#"getHTMLTagsAtPoint(%li,%li);",(long)pt.x,(long)pt.y]];
...
}
SNIPPET - in JSTools.js:
This is the function I use to get the element touched
function getHTMLTagsAtPoint(x,y) {
var tags = ",";
var element = document.elementFromPoint(x,y);
while (element) {
if (element.tagName) {
tags += element.tagName + ',';
}
element = element.parentNode;
}
return tags;
}
SNIPPET - loadJavascript
I use this one to inject my JS code in the webview
-(void)loadJavascript {
[self.WebView stringByEvaluatingJavaScriptFromString:
[NSString stringWithContentsOfFile:[[NSBundle mainBundle] pathForResource:#"JSTools" ofType:#"js"] encoding:NSUTF8StringEncoding error:nil]];
}
This part (everything I did to overrride the default UIActionSheet) is HEAVILY (should I say completely) based on
this post
#Freerunning's answer is complete (i did almost everything he said in my other classes, like on the post my code is based on), the snippets i posted is just to show you more "completely" how my code is.
Hope this helps! ^^
First of all thanks to Freerunnering for the great solution!
But you can do this with an UILongPressGestureRecognizer instead of a custom LongPressRecognizer. This makes things a bit easier to implement:
In the Viewcontroller Containing the webView:
Add UIGestureRecognizerDelegate to your ViewController
let mainJavascript = "function MyAppGetHTMLElementsAtPoint(x,y) { var tags = \",\"; var e = document.elementFromPoint(x,y); while (e) { if (e.tagName) { tags += e.tagName + ','; } e = e.parentNode; } return tags; } function MyAppGetLinkSRCAtPoint(x,y) { var tags = \"\"; var e = document.elementFromPoint(x,y); while (e) { if (e.src) { tags += e.src; break; } e = e.parentNode; } return tags; } function MyAppGetLinkHREFAtPoint(x,y) { var tags = \"\"; var e = document.elementFromPoint(x,y); while (e) { if (e.href) { tags += e.href; break; } e = e.parentNode; } return tags; }"
func viewDidLoad() {
...
let longPressRecognizer = UILongPressGestureRecognizer(target: self, action: #selector(CustomViewController.longPressRecognizerAction(_:)))
self.webView.scrollView.addGestureRecognizer(longPressRecognizer)
longPressRecognizer.delegate = self
...
}
func longPressRecognizerAction(sender: UILongPressGestureRecognizer) {
if sender.state == UIGestureRecognizerState.Began {
let tapPostion = sender.locationInView(self.webView)
let tags = self.webView.stringByEvaluatingJavaScriptFromString("MyAppGetHTMLElementsAtPoint(\(tapPostion.x),\(tapPostion.y));")
let href = self.webView.stringByEvaluatingJavaScriptFromString("MyAppGetLinkHREFAtPoint(\(tapPostion.x),\(tapPostion.y));")
let src = self.webView.stringByEvaluatingJavaScriptFromString("MyAppGetLinkSRCAtPoint(\(tapPostion.x),\(tapPostion.y));")
print("tags: \(tags)\nhref: \(href)\nsrc: \(src)")
// handle the results, for example with an UIDocumentInteractionController
}
}
// Without this function, the customLongPressRecognizer would be replaced by the original UIWebView LongPressRecognizer
func gestureRecognizer(gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWithGestureRecognizer otherGestureRecognizer: UIGestureRecognizer) -> Bool {
return true
}
And thats it!

What is the problem with the back button in my UIWebView?

I have an issue in my application that i wrote coding for the back button in my webView setEnabled = NO, but when the application is launched and webViewDidFinishLoad the back button setEnabled = YES. I tried all possibility to set the back button enabled is equal false but it not works.
-(IBAction) backButton : (id) sender{
backTapped = YES;
[webView goBack];
}
-(IBAction) fwdButton : (id) sender{
forwardTapped = YES;
[webView goForward];
}
- (void)webViewDidStartLoad:(UIWebView *)thisWebView{
NSLog(#"webViewDidStartLoad");
[progressWheel startAnimating];
progressWheel.hidden = NO;
if(!backTapped){
back.enabled = NO;
}
if (!forwardTapped) {
forward.enabled = NO;
}
}
- (void)webViewDidFinishLoad:(UIWebView *)thisWebView
{
[progressWheel stopAnimating];
progressWheel.hidden = YES;
if (!backTapped) {
[back setEnabled:thisWebView.canGoBack];
back.showsTouchWhenHighlighted = YES;
}
if (!forwardTapped) {
[forward setEnabled:thisWebView.canGoForward];
forward.showsTouchWhenHighlighted = YES;
}
}
I can't actually quite understand the problem you are having, but I can see two potential issues:
1) You set backTapped and forwardTapped to YES, but never set them to NO anywhere.
2) Perhaps you don't have "back" or "forward" buttons wired in you xib - if they are nil then back.enabled = NO will do nothing.
Edit:
This logic seems backwards:
if (!backTapped)
back.enabled = NO;
In your code you set backTapped to YES, then this code is hit so !backTapped is ! YES which is NO.
Try
if (backTapped)
back.enabled = NO;

Why isn't my UILabel being changed?

Why isn't my UILabel being changed? I am using the following code, and nothing is happening:
- (void)awakeFromNib {
percentCorrect.adjustsFontSizeToFitWidth;
percentCorrect.numberOfLines = 3;
percentCorrect.minimumFontSize = 100;
}
Here is my Implemintation code:
- (void) updateScore {
double percentScore = 100.0 * varRight / (varWrong + varRight);
percentCorrect.text = [NSString stringWithFormat:#"%.2f%%", percentScore];
}
- (void)viewDidLoad {
percentCorrect.adjustsFontSizeToFitWidth = YES;
percentCorrect.numberOfLines = 3;
percentCorrect.minimumFontSize = 100;
percentCorrect.text = #"sesd";
}
- (void)correctAns {
numberRight.text = [NSString stringWithFormat:#"%i Correct", varRight];
}
-(void)wrongAns {
numberWrong.text = [NSString stringWithFormat:#"%i Incorrect", varWrong];
}
#pragma mark Reset Methods
- (IBAction)reset:(id)sender; {
NSString *message = #"Are you sure you would like to reset?";
self.wouldYouLikeToReset = [[UIAlertView alloc] initWithTitle:#"Reset?" message:message delegate:self cancelButtonTitle:#"Cancel" otherButtonTitles:nil];
[wouldYouLikeToReset addButtonWithTitle:#"Continue"];
[self.wouldYouLikeToReset show];
// Now goes to (void)alertView and see's what is being pressed!
}
- (void)alertView:(UIAlertView *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex {
if (buttonIndex == 0)
{
NSLog(#"Cancel button pressed");
}
else
{
varRight = 0;
varWrong = 0;
[self wrongAns];
[self correctAns];
percentCorrect.text = [NSString stringWithFormat:#"0.0%%"];
}
}
#pragma mark Button Action Methods
- (IBAction)right:(id)sender; {
varRight++;
[self correctAns];
[self updateScore];
}
- (IBAction)wrong:(id)sender; {
varWrong++;
[self wrongAns];
[self updateScore];
}
- (IBAction)subOneRight:(id)sender {
if (varRight > 0 ) {
varRight--;
[self correctAns];
[self updateScore];
}
}
- (IBAction)subOneWrong:(id)sender {
if (varWrong > 0) {
varWrong--;
[self wrongAns];
[self updateScore];
}
}
-(IBAction)addHalfCredit:(id)sender;
{
varWrong++;
varRight++;
[self wrongAns];
[self correctAns];
[self updateScore];
}
#end
Any ideas?
Thanks
In order for the adjustsFontSizeToFitWidth setting to come into effect, the numberOfLines property must be set to 1. It won't work if it's != 1.
Are awakeFromNib, viewDidLoad, viewWillAppear being called at all?
The minimumFontSize property will do nothing if the text fits in the current bounds with the current font. Did you set the font property for the label?
percentCorrect.font = [UIFont systemFontOfSize:20];
Finally, isn't a minimumFontSize = 100 a little too big for a min font size?
Make sure everything is hooked up correctly. Make sure the IBOutlet for the UITextfield is setup and set break points within the method and see that the code is being touched. If it is, it's possible percentCorrect hasn't been hooked up correctly.
You shouldn't have to init your label if it is in the nib. If you are, then you created the label twice. So who knows which one you are messaging to. As soon as you initialized the label, you leaked the first one. So the label you have on screen is NOT the one you are manipulating in code.
Try placing your code in viewDidLoad instead. It should be initialized by then.
If that doesn't work, try viewDidAppear: simply to try to debug this.
It's possible that percentCorrect hasn't yet been initialized. Is percentCorrect equal to nil when that function is called, by any chance? If so, wait until after it's properly initialized to set its properties.
What are you expecting to happen? Does the label show when your code is commented out? How is percentCorrect defined in the nib?
Have you tried:
- (void)awakeFromNib {
percentCorrect.adjustsFontSizeToFitWidth = YES;
percentCorrect.numberOfLines = 3;
percentCorrect.minimumFontSize = 100;
percentcorrent.text = #"What is the text in percentCorrect?";
}
I had the same problem. Seems that setText doesn't automatically force a redraw when the change happens on a non-main thread. UI updates should always be done on the main thread to ensure responsiveness. There's another way to force it, using a selector:
label = [[UILabel alloc] init]; //assumes label is a data member of some class
...
(some later method where you want to update the label)
...
[label performSelectorOnMainThread:#selector(setText) withObject:#"New label value" waitUntilDone:false];
You may also get results from simply saying:
[label setNeedsDisplay];
which will force the update internally, but at the SDK's discretion. I found that didn't work for me, thus why I recommend the selector on the main thread.
What I found is sometimes , don't rely too much on IB , just add a line to set the frame :
labelx.frame=CGRectMake(labelx.frame.origin.x,labelx.frame.origin.y, 300, labelx.frame.size.height);
Then , autoresize works !