Jourdein

I thought there was an easy way such as enabling it in IB but seem I had to go to Google to find out how. For those who want to know how, here’s the original source.

Mainly, the codes involve on delegate functions:

- (void)textFieldDidBeginEditing:(UITextField *)textField

- (void)textFieldDidEndEditing:(UITextField *)textField

So, here’s the codes

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static const CGFloat KEYBOARD_ANIMATION_DURATION = 0.3;
static const CGFloat MINIMUM_SCROLL_FRACTION = 0.2;
static const CGFloat MAXIMUM_SCROLL_FRACTION = 0.8;
static const CGFloat PORTRAIT_KEYBOARD_HEIGHT = 216;
static const CGFloat LANDSCAPE_KEYBOARD_HEIGHT = 140;

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- (void)textFieldDidBeginEditing:(UITextField *)textField {
   [UIView beginAnimations:nil context:NULL];
   [UIView setAnimationBeginsFromCurrentState:YES];
   // the setAnimationBeginsFromCurrentState allow smooth transition
   // to new text field if the user taps on another
   [UIView setAnimationDuration:0.3];
 
   CGRect textFieldRect = [self.view.window convertRect:textField.bounds
                                               fromView:textField];
   CGRect viewRect = [self.view.window convertRect:self.view.bounds
                                               fromView:self.view];
 
   CGFloat midline = textFieldRect.origin.y + 0.5 * textFieldRect.size.height;
   // find the midline of textfield
   CGFloat numerator = midline - viewRect.origin.y - MINIMUM_SCROLL_FRACTION
                       * viewRect.size.height;
   CGFloat denominator = (MAXIMUM_SCROLL_FRACTION - MINIMUM_SCROLL_FRACTION)
                       * viewRect.size.height;
   CGFloat heightFraction = numerator / denominator;
 
   if (heightFraction < 0.0) { heightFraction = 0.0; }
   else if (heightFraction > 1.0) { heightFraction = 1.0; }
 
   animatedDistance = floor(PORTRAIT_KEYBOARD_HEIGHT*heightFraction);
   self.view.frame = CGRectMake(self.view.frame.origin.x,
   self.view.frame.origin.y-animatedDistance,
   self.view.frame.size.width,
   self.view.frame.size.height);
   [UIView commitAnimations];
}

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- (void)textFieldDidEndEditing:(UITextField *)textField
{
    CGRect viewFrame = self.view.frame;
    viewFrame.origin.y += animatedDistance;
 
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationBeginsFromCurrentState:YES];
    [UIView setAnimationDuration:KEYBOARD_ANIMATION_DURATION];
 
    [self.view setFrame:viewFrame];
 
    [UIView commitAnimations];
}

However, you could also refer to UICatalog example which also has example quite similar to this one but I prefer this one.

I’ve found 2 ways, currently, on how to hide keyboard when textfield lost focus on when user has done editing.

• Delegate method
• Callback for the event nbsp;nbsp;Did End On Exit

Delegate method

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- (BOOL)textFieldShouldReturn:(UITextField *)textField {
	[textField resignFirstResponder];
	return YES;
}

Very simple indeed. Just add this function in view where you want textfield to be delegated to.

Callback for event Did End On Exit

Outlines:

• Create dummy method: -(IBAction)endEditing:(id)sender;
• Connect event codeDid End On Exit/code to the dummy method created

References:

• iPhoneDevSDK

I was scratching my head of why the heck does the my tableview does not automatically update its data.

My binding:

NSArrayController = ACIssues
Controller Class = Issue Controller (have NSArray property subviewControllers)

ACIssues has it contentArray binded to subviewControllers’s array in Issue Controller. Somehow, changes made to the array of subviewControllers in Issue Controller does not reflect on other table which I had it binded to ACIssues.

After searching the internet, I found this

http://boredzo.org/blog/archives/2008-11-26/how-to-work-with-a-bound-to-array (open in new window)

Very good one. What it said… There’re right and wrong way to bind.

The right way is by using indexed accessors. Then, your Array Controller will see any changes you’ve made. What I did was creating indexed accessor methods.

- (void)insertObject:(id)object inSubviewControllersAtIndex:(unsigned)index {
[[self subviewControllers] insertObject:object atIndex:index];
}


- (void)removeObjectFromSubviewControllersAtIndex:(unsigned)index {
[[self subviewControllers] removeObjectAtIndex: index];
}

and calling it where I wanted to change the array.

[self insertObject:obj inSubviewControllersAtIndex:(index + 1)];
[self removeObjectFromSubviewControllersAtIndex:index];

the structure of this indexed accessor:

insertObject:(id)object inKeyAtIndex:(unsigned)index

where key is the property or in my case array that is binded to the Array Controller.