《精通 iOS 开发》第 05 章学习笔记

发表于 更新于 分类于 ， ， 阅读次数： 阅读次数： 本文字数： 2.8k 阅读时长 ≈ 3 分钟

单个控制器的旋转支持

代码示例：

1
2
3
- (NSUInteger)supportedInterfaceOrientations {
  return (UIInterfaceOrientationMaskPortrait | UIInterfaceOrientationMaskLandscapeLeft | UIInterfaceOrientationMaskLandscapeRight);
}

代码调整界面布局

在界面构造器中，将Use Autolayout复选框取消选中。

旋转时移动按钮

代码示例：

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
- (void)willAnimateRotationToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration {
  [self doLayoutForOrientation:toInterfaceOrientation];
}

- (void)doLayoutForOrientation:(UIInterfaceOrientation)orientation {
  if (UIInterfaceOrientationIsPortrait(orientation)) {
    [self layoutPortrait];
  } else {
    [self layoutLandscape];
  }
}

static const CGFloat buttonHeight = 40;
static const CGFloat buttonWidth = 120;
static const CGFloat spacing = 20;

- (void)layoutPortrait {
  CGRect b = self.view.bounds;

  CGFloat contentWidth = CGRectGetWidth(b) - (2 * spacing);
  CGFloat contentHeight = CGRectGetHeight(b) - (4 * spacing) - (2 * buttonHeight);

  self.contentView.frame = CGRectMake(spacing, spacing, contentWidth, contentHeight);

  CGFloat buttonRow1y = contentHeight + (2 * spacing);
  CGFloat buttonRow2y = buttonRow1y + buttonHeight + spacing;

  CGFloat buttonCol1x = spacing;
  CGFloat buttonCol2x = CGRectGetWidth(b) - buttonWidth - spacing;

  self.actionButton1.frame = CGRectMake(buttonCol1x, buttonRow1y, buttonWidth, buttonHeight);
  self.actionButton2.frame = CGRectMake(buttonCol2x, buttonRow1y, buttonWidth, buttonHeight);
  self.actionButton3.frame = CGRectMake(buttonCol1x, buttonRow2y, buttonWidth, buttonHeight);
  self.actionButton4.frame = CGRectMake(buttonCol2x, buttonRow2y, buttonWidth, buttonHeight);
}

- (void)layoutLandscape {
  CGRect b = self.view.bounds;

  CGFloat contentWidth = CGRectGetWidth(b) - buttonWidth - (3 * spacing);
  CGFloat contentHeight = CGRectGetHeight(b) - (2 * spacing);

  self.contentView.frame = CGRectMake(spacing, spacing, contentWidth, contentHeight);

  CGFloat buttonX = CGRectGetWidth(b) - buttonWidth - spacing;
  CGFloat buttonRow1y = spacing;
  CGFloat buttonRow4y = CGRectGetHeight(b) - buttonHeight - spacing;

  CGFloat buttonRow2y = buttonRow1y + floor((buttonRow4y - buttonRow1y) * 0.333);
  CGFloat buttonRow3y = buttonRow1y + floor((buttonRow4y - buttonRow1y) * 0.667);

  self.actionButton1.frame = CGRectMake(buttonX, buttonRow1y, buttonWidth, buttonHeight);
  self.actionButton2.frame = CGRectMake(buttonX, buttonRow2y, buttonWidth, buttonHeight);
  self.actionButton3.frame = CGRectMake(buttonX, buttonRow3y, buttonWidth, buttonHeight);
  self.actionButton4.frame = CGRectMake(buttonX, buttonRow4y, buttonWidth, buttonHeight);
}

获取视图加载完后的屏幕方向

代码示例：

1
2
3
4
5
6
7
- (void)viewDidLoad {
  [super viewDidLoad];
  // Do any additional setup after loading the view, typically from a nib.
  UIApplication *app = [UIApplication sharedApplication];
  UIInterfaceOrientation currentOrientation = app.statusBarOrientation;
  [self doLayoutForOrientation:currentOrientation];
}