使用自动布局在横向中进行不同的布局

Question

当我的应用旋转为横向时，我想使用不同的布局，请参阅以下图片：纵向：

风景：

蓝色方框代表UITextFields。

在仍使用自动布局的情况下将设备旋转为横向时重新排列它们的最简单方法是什么？

Answer 1

您需要为横向/纵向方向添加单独的约束。请参阅以下示例，它将对您有所帮助。这里我只为一个文本字段添加了约束。

textfld1.translatesAutoresizingMaskIntoConstraints = NO;


- (void) willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration
{
    [textfld1 removeConstraints:textfld1.constraints];
    [self.view removeConstraints:self.view.constraints];

    if (toInterfaceOrientation == UIInterfaceOrientationPortrait || toInterfaceOrientation == UIInterfaceOrientationPortraitUpsideDown) {

        //You can use either center horizontally or Leading
        [self.view addConstraint:[NSLayoutConstraint constraintWithItem:textfld1
                                                              attribute:NSLayoutAttributeLeading
                                                              relatedBy:NSLayoutRelationEqual
                                                                 toItem:self.view
                                                              attribute:NSLayoutAttributeLeading
                                                             multiplier:1.0
                                                               constant:234.0]];

        //        // Center horizontally
        //        [self.view addConstraint:[NSLayoutConstraint constraintWithItem:textfld1
        //                                                              attribute:NSLayoutAttributeCenterX
        //                                                              relatedBy:NSLayoutRelationEqual
        //                                                                 toItem:self.view
        //                                                              attribute:NSLayoutAttributeCenterX
        //                                                             multiplier:1.0
        //                                                               constant:0.0]];

        [self.view addConstraint:[NSLayoutConstraint constraintWithItem:textfld1
                                                              attribute:NSLayoutAttributeTop
                                                              relatedBy:NSLayoutRelationEqual
                                                                 toItem:self.view
                                                              attribute:NSLayoutAttributeTop
                                                             multiplier:1.0
                                                               constant:100.0]];


    }else if (toInterfaceOrientation == UIInterfaceOrientationLandscapeLeft || toInterfaceOrientation == UIInterfaceOrientationLandscapeRight){

        [self.view addConstraint:[NSLayoutConstraint constraintWithItem:textfld1
                                                              attribute:NSLayoutAttributeLeading
                                                              relatedBy:NSLayoutRelationEqual
                                                                 toItem:self.view
                                                              attribute:NSLayoutAttributeLeading
                                                             multiplier:1.0
                                                               constant:120.0]];

        [self.view addConstraint:[NSLayoutConstraint constraintWithItem:textfld1
                                                              attribute:NSLayoutAttributeTop
                                                              relatedBy:NSLayoutRelationEqual
                                                                 toItem:self.view
                                                              attribute:NSLayoutAttributeTop
                                                             multiplier:1.0
                                                               constant:140.0]];

    }

    [self.view addConstraint:[NSLayoutConstraint constraintWithItem:textfld1
                                                          attribute:NSLayoutAttributeHeight
                                                          relatedBy:NSLayoutRelationEqual
                                                             toItem:nil
                                                          attribute:NSLayoutAttributeNotAnAttribute
                                                         multiplier:1.0
                                                           constant:30]];

    [self.view addConstraint:[NSLayoutConstraint constraintWithItem:textfld1
                                                          attribute:NSLayoutAttributeWidth
                                                          relatedBy:NSLayoutRelationEqual
                                                             toItem:nil
                                                          attribute:NSLayoutAttributeNotAnAttribute
                                                         multiplier:1.0
                                                           constant:300]];

}