iPhone development common problems with UITextField and UITextViews - iphone

Question

I've been using iPhone SDK from last 2 months.
One thing I observed is SDK isn't very nice in terms of getting text inputs.
Everytime I use a UITextView and UITextField followings are the common problems I always have to deal with:
Keyboard overlaps the textinput.
There is not a default way to hide the keyboard.
Although I know how to deal with both, for the first, I scrolls up the entire view at the keyboardshown notification call and to hide I know resignFirstResponder.
Here is how I deal with this.
But I hate the way I work!!
I don't want to copy the same code at all the .h and .m files.
I love the way the safari keyboard works like toolbar.
Kindly advice me if there is any reusable class I can use in my projects to tackle the problem.
I am sure there should be some re-usable solution to this problem as this is the common problem every developer must have seen!

Answer 1

UITableViewController will automatically resize its UITableView when keyboard is shown/hidden. If your UI has table-like design, you can place your controls inside UITableView so you won't have to implement resizing manually.

Answer 2

While it can be a pain, how could Apple possibly code that functionality to account for every possible use case?
Instead, you need to figure out what your common use cases are and then program accordingly. This is object-oriented programming - code reuse is encouraged! But, if you are copying and pasting between projects, you are doing it wrong.
For example, it is very common for me to do this with text inputes in UITableViews that are not part of a UITableView controller. Obviously, the keyboard becomes a problem that I need to fix.
So, do I write the necessary code to fix it every time? Nope, I wrote it once in a UITableView subclass and I use that class in all my projects.
Remember, good programmers are lazy and will use the tools available to them to avoid writing the same thing over and over. Create your own class, categories, etc. to handle you common problems and you'll be fine.

Answer 3

Textfield's and scrolling view in up/down's. using NSNotificationCenter code.
Write code in "viewDidLoad":
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector (keyboardDidShow:)
name: UIKeyboardDidShowNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector (keyboardDidHide:)
name: UIKeyboardDidHideNotification object:nil];
add to code in delegate methods:
-(void) keyboardDidShow: (NSNotification *)notif
{ [calendarView removeFromSuperview];
// If keyboard is visible, return
if (keyboardVisible)
{
NSLog(#"Keyboard is already visible. Ignore notification.");
return;
}
// Keyboard is now visible
keyboardVisible = YES;
}
-(void) keyboardDidHide: (NSNotification *)notif
{ [calendarView removeFromSuperview];
// Is the keyboard already shown
if (!keyboardVisible)
{
NSLog(#"Keyboard is already hidden. Ignore notification.");
return;
}
if (up == 1) {
up = 0;
[self down];
}
// Keyboard is no longer visible
keyboardVisible = NO;
}
add to remaining default methods:
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
if(textField == txt_Zip){
NSString *newString = [textField.text stringByReplacingCharactersInRange:range withString:string];
return !([newString length] > 6);
}
else {
return YES;
}
}
-(void) touchesBegan :(NSSet *) touches withEvent:(UIEvent *)event
{
if(up==1)
{
up=0;
[self down];
}
[txtMake_Model resignFirstResponder];
[txtSerial_Vin resignFirstResponder];
[txtDaysPerWeek resignFirstResponder];
[txtAnnualMiles resignFirstResponder];
[txtPurchasedDate resignFirstResponder];
[txtInterestLocation resignFirstResponder];
[txtInterestSequence resignFirstResponder];
[txtInterestName resignFirstResponder];
[txt_City resignFirstResponder];
[txtAddress1 resignFirstResponder];
[txtAddress2 resignFirstResponder];
[txt_Zip resignFirstResponder];
[txtAdditionalInfo resignFirstResponder];
[txtVehicleNumber resignFirstResponder];
[txtMilesToWork resignFirstResponder];
[txtCostNew resignFirstResponder];
[super touchesBegan:touches withEvent:event ];
}
//- (BOOL)textFieldShouldReturn:(UITextField *)textField // called when 'return' key pressed. return NO to ignore.
//{
// [textField resignFirstResponder];
// return YES;
//}
- (BOOL)textFieldShouldReturn:(UITextField *)textField{
[textField resignFirstResponder];
if (up==1) {
up =0;
[self down];
}
return YES ;
}
- (void)textFieldDidBeginEditing:(UITextField *)textField{
if(textField == txtInterestSequence)
{ if(up==0){up=1;[self moveUp];}
}else if(textField == txtInterestName)
{ if(up==0){up=1;[self moveUp];}
}else if(textField == txtAddress1)
{ if(up==0){up=1;[self moveUp];}
} else if(textField == txtAddress2)
{ if(up==0){up=1;[self moveUp];}
} else if(textField == txt_City)
{ if(up==0){up=1;[self moveUp];}
} else if(textField == txt_Zip)
{ if(up==0){up=1;[self moveUp];}
} else if(textField == txtAdditionalInfo)
{ if(up==0){up=1;[self moveUp];}
} else if(textField == txtMilesToWork)
{ if(up==0){up=1;[self moveUp];}
} else if(textField == txtCostNew)
{ if(up==0){up=1;[self moveUp];}
}
}
-(void)moveUp{
// up=1;
[UIView beginAnimations:nil context:nil];
self.view.center=CGPointMake(self.view.center.x, self.view.center.y-200);
[UIView commitAnimations];
}
-(void)down{
[UIView beginAnimations:nil context:nil];
self.view.center=CGPointMake(self.view.center.x, self.view.center.y+200);
[UIView commitAnimations];
// up=0;
}