I'm new to Cocoa Touch and I'm just messing around trying to get a feel for the language and framework. So I'm just trying to create a simple app that takes text from a UITextField and just shows it in a UIAlertView here is the action method:
- (IBAction)showNotifAction:(id)sender {
putVal = _TextToDisplay.text;
_alertOne.title = #"Message";
_alertOne.message = putVal;
[_alertOne show];
}
For some reason it breaks on line 3 with a SIGART. Is there something I'm doing wrong? Oh, BTW, here is my AppDelegate implementation:
#interface LearnAppDelegate : NSObject <UIApplicationDelegate> {
UITextField *_TextToDisplay;
UIButton *_ShowNotif;
UIAlertView *_alertOne;
NSString *putVal;
}
You need to define your UIAlertVIew. Pointer that you are trying to use points to nothing or to garbaged memory.
Try something like the following code:
UIAlertView *alert = [[[UIAlertView alloc] initWithTitle:"My title"
message:putVal
delegate:nil
cancelButtonTitle:#"OK"
otherButtonTitles:nil] autorelease];
[alert show];
Related
I have several view controllers that need to make Parse services calls, which is therefore handled in a class for every "Parse" related work.
Now I have a case where the parse response will (if no errors comes up obviously) instantiate the MFMessageComposeViewController with certain parameters.
The text body comes from parse, the recipients comes from the class.
My problem is : I have copy/pasted code that I can't get rid off because I don't know what to do
In my controller class, I do this :
- (void)showSMS:(NSString*)reciever { //This is the phone number
if(![MFMessageComposeViewController canSendText]) {
UIAlertView *warningAlert = [[UIAlertView alloc] initWithTitle:NSLocalizedString(#"ALERT_ERROR_Title", nil) message:NSLocalizedString(#"ALERT_ERROR_NOSMS", nil) delegate:nil cancelButtonTitle:#"Ok" otherButtonTitles:nil];
[warningAlert show];
return;
}
[[ParseService sharedInstance]sendSMSOfType:SMS_TYPE_INSIST toRecipient:reciever andBlock:^(NSError *error, NSString *body) {
if (!error){
MFMessageComposeViewController *messageController = [[MFMessageComposeViewController alloc] init];
messageController.messageComposeDelegate = self;
NSArray *recipents = [[NSArray alloc]initWithObjects:reciever, nil];
[messageController setRecipients:recipents];
[messageController setBody:body];
[self presentViewController:messageController animated:YES completion:nil];
}else{
UIAlertView *warningAlert = [[UIAlertView alloc] initWithTitle:#"Error getting sms" message:#"Couldn't get the text online" delegate:nil cancelButtonTitle:#"Ok" otherButtonTitles:nil];
[warningAlert show];
return;
}
}];
}
and I have this exact same block of code in 3 different places, except for ONE difference, the SMS_TYPE parameter.
How should I tweak this so I don't have to create and assign the parameters in every controller, have one neat line that would look like this [??? setUpMessageControllerWithParam:recipients:body];
Pretty much the whole completion block here troubles me, but I can't really put it somewhere else because I'll have trouble presenting a view on self if self isn't a VC, same goes for delegates and alerts.
This is probably simple for most of you, I'm just OOP-retarded. Any help is much appreciated :)
There are several ways to do the this ... like creating a base view controller with this method passing the custom parameters and inheriting your other view controllers from it, or you can make a Category with this method and import this category and use wherever you need ...
I'm trying to display a custom UIAlertView and I'm using AHAlertView:
https://github.com/warrenm/AHAlertView
I added both AHAlertView.m and .h to my project and add the following to the viewDidLoad method:
NSString *title = #"Alert View Title";
NSString *message = #"This is a message that might prompt you to do something.";
AHAlertView *alert = [[AHAlertView alloc] initWithTitle:title message:message];
__weak AHAlertView *weakAlert = alert;
[alert setCancelButtonTitle:#"Cancel" block:^{
weakAlert.dismissalStyle = AHAlertViewDismissalStyleTumble;
}];
[alert addButtonWithTitle:#"OK" block:^{
weakAlert.dismissalStyle = AHAlertViewDismissalStyleZoomDown;
}];
[alert show];
The problem is when I'm tapping either one of the buttons, the app crashes with:
"Application windows are expected to have a root view controller at the end of application launch"
I don't know what I did wrong, I looked at the sample project and this is the way the alert is being used.
How can I implement it correctly?
Did you activate -fno-objc-arc option ? If you did, deactivate it, AHAlertView support ARC
I have code setting up a UIAlertView:
-(IBAction)showMessage
{
//NSInteger *buttonIndex = NULL;
UIAlertView *message = [[UIAlertView alloc] initWithTitle:nil
message:nil
delegate:nil
cancelButtonTitle:#"Cancel"
otherButtonTitles:#"Email",#"SMS",#"Facebook",#"Twitter", nil];
[message show];
}
and code explaining what to do once the user makes a choice:
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
if (buttonIndex == 1){
[self openMail];
}
else if (buttonIndex == 2)
//etc.
}
But what I can't figure out is how to connect the two. The obvious answer is to add a line to the first piece of code calling alertView: clickedButtonAtIndex on UIAlertView *message, but how do you assign buttonIndex? How do you tell alertView whether the user has chosen Facebook, Email, etc?
Add to the header file if you haven't already:
#interface YourClass : UIViewController <UIAlertViewDelegate>
{
}
...etc
and in your AlertView code change delegate:nil to delegate:self
For more information have a look at the Apple Docs:
http://developer.apple.com/library/ios/#DOCUMENTATION/UIKit/Reference/UIAlertViewDelegate_Protocol/UIAlertViewDelegate/UIAlertViewDelegate.html
From the docs:
The button indices start at 0. If this is the cancel button index, the alert view is canceling. If -1, the cancel button index is not set.
(1) You want to set delegate:self when you initialize the message. Also, in your interface declaration, do something like:
#interface myClass: UIViewController <UIAlertViewDelegate>
This way, your handler function automatically gets called when the user makes a selection.
(2) Buttons are indexed in the order you listed them.
(3) Since you have a lot of options for the user to choose from, it is better to use UIActionSheet instead of UIAlertView. Alerts are generally used for simple Yes/No-type selections.
Hope this helps!
I am implementing an alert view after the user clicks on the 'destructButton' in an action sheet. Code snippet as below:
-(void)actionSheet:(UIActionSheet *)actionSheet didDismissWithButtonIndex:(NSInteger)buttonIndex
{
if (buttonIndex != actionSheet.cancelButtonIndex)
{
UIAlertView *alert = [[UIAlertView alloc]
initWithTitle:#"Something happened!"
message:nil
delegate:nil
cancelButtonTitle:#"Phew!"
otherButtonTitles:nil];
}
[alert show];
[alert release];
}
I have already included the UIActionSheetDelegate protocol in my .h file
#interface Control_FunViewController : UIViewController <UIActionSheetDelegate> {
UITextField *nameField;
UITextField *numberField;
UILabel *sliderLabel;
UISwitch *leftSwitch;
UISwitch *rightSwitch;
UIButton *doSomethingButton;
}
But when I click on the destructButton in the actionsheet, nothing happens. Am I missing something here?
Thanks
Zhen
Your delegate needs to implement actionSheet:clickedButtonAtIndex:.
Action sheet will be dismissed after actionSheet:clickedButtonAtIndex: and after that the delegate will receive actionSheet:didDismissWithButtonIndex: .
From Apple Action Sheet Delegate Protocol reference
... the delegate must implement the
actionSheet:clickedButtonAtIndex:
message to respond when those buttons
are clicked; otherwise, your custom
buttons do nothing. The action sheet
is automatically dismissed after the
actionSheet:clickedButtonAtIndex:
delegate method is invoked.
You can have a look at example projects that use UIActionSheet like GenericKeychain :
// Action sheet delegate method.
- (void)actionSheet:(UIActionSheet *)actionSheet
clickedButtonAtIndex:(NSInteger)buttonIndex
{
// the user clicked one of the OK/Cancel buttons
if (buttonIndex == 0)
{
[passwordItem resetKeychainItem];
[accountNumberItem resetKeychainItem];
[self.tableView reloadData];
}
}
You have added UIActionSheetDelegate on .h file. Not this only enough. You also have to set delegate for the UIActionSheet object. Refer this below coding:
-(void)showActionSheet
{
UIActionSheet *action =[[UIActionSheet alloc]initWithTitle:#"dsfs" delegate:self cancelButtonTitle:#"First Btn" destructiveButtonTitle:#"Dest Btn" otherButtonTitles:nil];
[action showInView:self.view];
}
In that code, I have set the delegate of UIActionSheet to self, this works if you have added this method on your ViewController (Control_FunViewController).
I'd like to call a method
[self someMethod:bar]
But how can I open an AlertView before? someMethoud should wait for AlterView OK-Button. Do i need to write a complex task manager? Or is there a smart solution?
display the alert, and when the user clicks the button, then call your method.
remember to add the delegate to your class
#interface YourViewController : UIViewController <UIAlertViewDelegate>
code in your controller
// display the alert
UIAlertView *alert = [[UIAlertView alloc]initWithTitle:#"Alert" message:#"Message"
delegate:self cancelButtonTitle:#"Ok" otherButtonTitles:nil];
[alert show];
[alert release];
}
// UIAlertViewDelegate method - get the click here and take action
- (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex {
if (buttonIndex == 0) {
// ok button pushed
[self someMethod:bar];
}
}
You would need to implement the delegate method didDismissWithButtonIndex here http://developer.apple.com/library/ios/ipad/#documentation/UIKit/Reference/UIAlertViewDelegate_Protocol/UIAlertViewDelegate/UIAlertViewDelegate.html
The, depending on the button that was tapped, you would call your method.