Question

我将UITextView定位在屏幕的中央，无论我是在横向还是纵向位置（iPhone或iPad），都能正常工作。问题是当我旋转设备时它不会停留在中心位置。我以为它会自动留在中心。

由于文本视图是在viewWillAppear中创建的，我想知道是否有办法刷新设备方向的视图。或者只是简单地移动视图。

我的代码如下：

-(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

最好在UIView的情况下在layoutSubviews中布局子视图，在UIViewController的情况下在viewDidLayoutSubviews。所以在你的情况下，你可以简单地做：

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

假设你在一个属性上有infoTextView。

替代方案和更好的方法是使用Autolayout并在视图中添加水平和垂直位置约束。

Answer 2

另一种解决方案是在textView上设置约束，并告诉它在超级视图上垂直和水平对齐。

Answer 3

用以下代码替换代码：

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 4

在代码中使用这些方法。并在 - （void）landScapeFrame中写下横向代码并在 - （void）potraitFrame中写下您的肖像代码

#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;
}
}

在设备方向上设置UITextVIew位置

4 个答案: