Set UITextVIew position on device orientation

Question

I am positioning a UITextView at the center of the screen, which works fine whether I'm on landscape or portrait position (iPhone or iPad). The problem is that it does not stay at the center when I rotate the device. I thought it would automatically stay at the center.

Since the text view is create in viewWillAppear I am wondering if there's a way to refresh the view on device orientation. Or perhaps simply to move the view.

My code below:

-(void)viewWillAppear:(BOOL)animated{
    [super viewWillAppear:animated];
    UITextView *infoTextView = [[UITextView alloc] init];
    infoTextView.frame = CGRectMake(0, 0, 300.0, 300.0);
    infoTextView.center = CGPointMake(CGRectGetWidth(self.view.bounds)/2.0f, CGRectGetHeight(self.view.bounds)/2.0f);
    infoTextView.backgroundColor = [UIColor clearColor];
    NSString *anotherViewText = @"This is the content";
    infoTextView.dataDetectorTypes = UIDataDetectorTypeLink;
    infoTextView.text = anotherViewText;
    [infoTextView setFont:[UIFont fontWithName:@"ArialMT" size:18]];
    infoTextView.editable = NO;
    infoTextView.textAlignment=NSTextAlignmentCenter;
    [self.view addSubview:infoTextView];  
}

Answer 1

Replace the code with this:

UITextView *infoTextView = [[UITextView alloc] init];

infoTextView.frame = CGRectMake(0, 0, 300.0, 300.0);

infoTextView.center = self.view.center;

infoTextView.autoresizingMask = UIViewAutoresizingNone;

infoTextView.backgroundColor = [UIColor clearColor];

NSString *anotherViewText = @"This is the content";

infoTextView.dataDetectorTypes = UIDataDetectorTypeLink;

infoTextView.text = anotherViewText;

[infoTextView setFont:[UIFont fontWithName:@"ArialMT" size:18]];

infoTextView.editable = NO;

infoTextView.textAlignment=NSTextAlignmentCenter;

[self.view addSubview:infoTextView];

Answer 2

It is a good practice to layout your subviews in layoutSubviews in case of UIView or viewDidLayoutSubviews in case of UIViewController. So in your case, you could simply do:

- (void)viewDidLayoutSubviews {
  [super viewDidLayoutSubviews];
  self.infoTextViewCenter = self.view.center;
}

That's assuming you have infoTextView on a property.

Alternative and better approach is to use Autolayout and add horizontal and vertical position constraints to your view.

Answer 3

Use these method in the code. and write you landscape code inside the -(void)landScapeFrame and write your portrait code inside the -(void)potraitFrame

#pragma mark - Auto rotate methods
#pragma mark for pre - iOS 6

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
BOOL returnval=NO;

if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad)
{
    if(interfaceOrientation==UIInterfaceOrientationPortrait||interfaceOrientation==UIInterfaceOrientationPortraitUpsideDown)
    {
        [self potraitFrame];
    }
    else
    {
        [self landScapeFrame];
    }
    returnval = YES;
}
else
{
    [self landScapeFrame];
    returnval= (interfaceOrientation==UIInterfaceOrientationLandscapeLeft || interfaceOrientation==UIInterfaceOrientationLandscapeRight);
}
return returnval;
}

 #pragma mark for - iOS 6

 -(BOOL)shouldAutorotate
 {
return YES;
 }

 -(void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation  duration:(NSTimeInterval)duration {

if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad)
{
           if(toInterfaceOrientation==UIInterfaceOrientationPortrait||toInterfaceOrientation==UIInterfaceOrientationPortraitUpsideDown)
    {
        [self potraitFrame];
    }
    else
    {
        [self landScapeFrame];
    }
}
else
{
    [self landScapeFrame];
}

}

-(void)willAnimateRotationToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration {

}
-(UIInterfaceOrientation)preferredInterfaceOrientationForPresentation
{
 UIInterfaceOrientationLandscapeLeft;
if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad)
{
    return self.interfaceOrientation;
}
else
{
    UIInterfaceOrientation crntOrntatn = self.interfaceOrientation;
    return UIInterfaceOrientationIsLandscape(crntOrntatn) ? crntOrntatn : UIInterfaceOrientationLandscapeLeft;
}

}

 -(NSUInteger)supportedInterfaceOrientations
 {
if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad)
{
    return UIInterfaceOrientationMaskAll;   
}
else
{
    return UIInterfaceOrientationMaskLandscape;
}
}

Answer 4

Another solution is just to set constraints on your textView and tell it to be vertically and horizontally aligned on your superview.