在做视频开发时遇到屏幕旋转问题,其中涉及到 statusbar、 uinavigationcontroller、uitabbarcontroller 、uiviewcontroller 。
在设备锁屏下的整体效果图
ios-旋转.gif
主要涉及以下4点：
- 横竖屏的旋转
- 屏幕旋转相应改变视图位置
- 旋转时状态栏的隐藏与显示
- 锁屏
1、横竖屏旋转
第1步：
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-(uiinterfaceorientationmask)application:(uiapplication *)application supportedinterfaceorientationsforwindow:(uiwindow *)window {// nslog(@"0000000---------%@",nsstringfromclass([[self topviewcontroller] class]));// if ([nsstringfromclass([[self topviewcontroller] class]) isequaltostring:@"firstviewcontroller"]) {// //横屏// return uiinterfaceorientationmasklandscaperight;// }// //竖屏// return uiinterfaceorientationmaskportrait; nsuinteger orientations = uiinterfaceorientationmaskallbutupsidedown; if(self.window.rootviewcontroller){ //取出当前显示的控制器 uiviewcontroller *presentedviewcontroller = [self topviewcontrollerwithrootviewcontroller:self.window.rootviewcontroller]; //按当前控制器支持的方向确定旋转方向(将旋转方向重新交给每个控制器自己控制) nslog(@"%s, line = %d",__function__,__line__); orientations = [presentedviewcontroller supportedinterfaceorientations]; } return orientations;}//获取界面最上层的控制器//- (uiviewcontroller*)topviewcontroller {// nslog(@"%s, line = %d",__function__,__line__);// return [self topviewcontrollerwithrootviewcontroller:[uiapplication sharedapplication].keywindow.rootviewcontroller];//}//一层一层的进行查找判断- (uiviewcontroller*)topviewcontrollerwithrootviewcontroller:(uiviewcontroller*)rootviewcontroller { nslog(@"%s, line = %d",__function__,__line__); if ([rootviewcontroller iskindofclass:[uitabbarcontroller class]]) { uitabbarcontroller* tabbarcontroller = (uitabbarcontroller*)rootviewcontroller; nslog(@"tabbar:%@",nsstringfromclass([tabbarcontroller.selectedviewcontroller class])); return [self topviewcontrollerwithrootviewcontroller:tabbarcontroller.selectedviewcontroller]; } else if ([rootviewcontroller iskindofclass:[uinavigationcontroller class]]) { uinavigationcontroller* nav = (uinavigationcontroller*)rootviewcontroller; nslog(@"nav:%@",nsstringfromclass([nav.visibleviewcontroller class])); return [self topviewcontrollerwithrootviewcontroller:nav.visibleviewcontroller]; } else if (rootviewcontroller.presentedviewcontroller) { nslog(@"present:%@",nsstringfromclass([rootviewcontroller.presentationcontroller class])); uiviewcontroller* presentedviewcontroller = rootviewcontroller.presentedviewcontroller; return [self topviewcontrollerwithrootviewcontroller:presentedviewcontroller]; } else { nslog(@"root:%@",rootviewcontroller); return rootviewcontroller; }} |
代码中通过 -(uiinterfaceorientationmask)application:(uiapplication *)application supportedinterfaceorientationsforwindow:(uiwindow *)window 方法将控制器交给自己控制，该方法默认值为 info.plist 中配置的 supported interface orientations 项的值。
第2步：在各控制器设置支持的方向
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//是否允许旋转(默认允许)- (bool)shouldautorotate { return yes;}- (uiinterfaceorientationmask)supportedinterfaceorientations{ //允许旋转的方向 return uiinterfaceorientationmaskall;} |
其中 - supportedinterfaceorientations 方法在 ipad 中默认取值为 uiinterfaceorientationmaskall ，即默认支持所有屏幕方向；而 iphone 跟 ipod touch 的默认取值为 uiinterfaceorientationmaskallbutupsidedown ，即支持除竖屏向下以外的三个方向。
在设备屏幕旋转时，系统会调用 - shouldautorotate 方法检查当前界面是否支持旋转，只有 - shouldautorotate 返回 yes 的时候， - supportedinterfaceorientations 方法才会被调用，以确定是否需要旋转界面。
这个是 tabbarcontroller 中设置的,它会影响关联的 uiviewcontroller 的支持方向，需要在 uiviewcontroller 中进一步设置
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//此方法来控制能否横竖屏 控制锁屏 - (uiinterfaceorientationmask)supportedinterfaceorientations { nslog(@"%s, line = %d",__function__,__line__); uiinterfaceorientationmask inter; if (_lockscreen) { switch (_lockorientation) { case 1: inter = uiinterfaceorientationmaskportrait; break; case 2: inter = uiinterfaceorientationmaskportraitupsidedown; break; case 3: inter = uiinterfaceorientationmasklandscaperight; break; case 4: inter = uiinterfaceorientationmasklandscapeleft; break; default:inter = uiinterfaceorientationmaskall; break; } } else { inter = uiinterfaceorientationmaskall; } //支持全部方向 return inter; } |
第3步：强制转换控制器方向
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- (void)setinterorientation:(uiinterfaceorientation)orientation { if ([[uidevice currentdevice] respondstoselector:@selector(setorientation:)]) { sel selector = nsselectorfromstring(@"setorientation:"); nsinvocation *invocation = [nsinvocation invocationwithmethodsignature:[uidevice instancemethodsignatureforselector:selector]]; [invocation setselector:selector]; [invocation settarget:[uidevice currentdevice]]; int val = orientation; // 从2开始是因为0 1 两个参数已经被selector和target占用 [invocation setargument:&val atindex:2]; [invocation invoke]; } } |
这样就可以完成横竖屏的切换。
2、屏幕旋转相应改变视图位置
这里先扩展 uideviceorientation & uiinterfaceorientation 的知识
uideviceorientation 设备的物理方向
uideviceorientation 即我们手持的移动设备的 orientation ，是一个三围空间,有六个方向,通过 [uidevice currentdevice].orientation 获取当前设备的方向。
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typedef ns_enum(nsinteger, uideviceorientation) { uideviceorientationunknown, uideviceorientationportrait, uideviceorientationportraitupsidedown, // device oriented vertically, home button on the top 竖屏向下，即头在下，home 键在上 uideviceorientationlandscapeleft, // device oriented horizontally, home button on the right 横屏头在左，home键在右 uideviceorientationlandscaperight, // device oriented horizontally, home button on the left 横屏头在右，home键在左 uideviceorientationfaceup, // device oriented flat, face up uideviceorientationfacedown // device oriented flat, face down} ; |
uiinterfaceorientation 界面的显示方向
uiinterfaceorientation 即我们看到的视图的 orientation ，可以理解为 statusbar 所在的方向，是一个二维空间，有四个方向, 通过 [uiapplication sharedapplication].statusbarorientation 即状态栏的方向获取当前界面方向。
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// note that uiinterfaceorientationlandscapeleft is equal to uideviceorientationlandscaperight (and vice versa).// this is because rotating the device to the left requires rotating the content to the right.typedef ns_enum(nsinteger, uiinterfaceorientation) { uiinterfaceorientationunknown = uideviceorientationunknown, uiinterfaceorientationportrait = uideviceorientationportrait, uiinterfaceorientationportraitupsidedown = uideviceorientationportraitupsidedown, uiinterfaceorientationlandscapeleft = uideviceorientationlandscaperight, uiinterfaceorientationlandscaperight = uideviceorientationlandscapeleft} |
uiinterfaceorientationmask 支持的方向
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// ios 6 之后用于控制界面的枚举值typedef ns_options(nsuinteger, uiinterfaceorientationmask) { uiinterfaceorientationmaskportrait = (1 << uiinterfaceorientationportrait), uiinterfaceorientationmasklandscapeleft = (1 << uiinterfaceorientationlandscapeleft), uiinterfaceorientationmasklandscaperight = (1 << uiinterfaceorientationlandscaperight), uiinterfaceorientationmaskportraitupsidedown = (1 << uiinterfaceorientationportraitupsidedown), uiinterfaceorientationmasklandscape = (uiinterfaceorientationmasklandscapeleft | uiinterfaceorientationmasklandscaperight), uiinterfaceorientationmaskall = (uiinterfaceorientationmaskportrait | uiinterfaceorientationmasklandscapeleft | uiinterfaceorientationmasklandscaperight | uiinterfaceorientationmaskportraitupsidedown), uiinterfaceorientationmaskallbutupsidedown = (uiinterfaceorientationmaskportrait | uiinterfaceorientationmasklandscapeleft | uiinterfaceorientationmasklandscaperight),} |
由上可以发现：
ios 6 及之后版本使用的 uiinterfaceorientationmask 类型来控制屏幕屏幕方向，该类型也新增加了几个枚举取值，可用一个枚举取值来代表多个屏幕方向，使用起来更方便。
注意在 uiinterfaceorientation 中有注释
note that uiinterfaceorientationlandscapeleft is equal to uideviceorientationlandscaperight (and vice versa).
this is because rotating the device to the left requires rotating the content to the right，大意是界面的左转相当于设备的右转，如果设备向左转时就需要内容（即界面）向右转。即：
uiinterfaceorientationlandscapeleft = uideviceorientationlandscaperight
uiinterfaceorientationlandscaperight = uideviceorientationlandscapeleft
下面还会举例说明。
其实 uideviceorientation 与 uiinterfaceorientation 是两个互不相干的属性，通常情况下会一起出现，在这里正好利用此特性在屏幕旋转后进行重新布局。
第1步：监听 uideviceorientationdidchangenotification 状态
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//监听设备旋转 改变 视图 对应位置 [[nsnotificationcenter defaultcenter] addobserver:self selector:@selector(deviceorientationdidchange) name:uideviceorientationdidchangenotification object:nil];//用来控制横竖屏时调整视图位置- (void)deviceorientationdidchange{ [self isportrait]; } |
第2步：重新布局
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if (_interorientation == uiinterfaceorientationportrait || _interorientation == uiinterfaceorientationportraitupsidedown) { self.top.constant = 145; self.bottom.constant = 210; } else if (_interorientation == uiinterfaceorientationlandscaperight || _interorientation == uiinterfaceorientationlandscapeleft) { self.top.constant = 40; self.bottom.constant = 50; } |
例如：竖屏转横屏
界面竖屏 uiinterfaceorientationportrait ->横屏 uiinterfaceorientationlandscaperight ，设备方向 uideviceorientationportrait -> uideviceorientationlandscapeleft ,在设备发生变化这个过程触发 uideviceorientationdidchangenotification 监听，然后进行重新布局。
3、旋转时状态栏的隐藏与显示
这里只记述旋转时状态栏的变化，由竖屏想横屏变化时状态栏会消失。
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//在需要的`uiviewcontroller`设置是否隐藏- (bool)prefersstatusbarhidden { nslog(@"%s, line = %d",__function__,__line__); return no;} |
4、锁屏
锁屏时，不管系统锁屏是否关闭、push 或 present 返回后，界面依然保持不变。
第1步：设置锁屏
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- (ibaction)lockaction:(uibutton *)sender { if (_lockscreen) { _lockscreen = no; [sender settitle:@"锁定屏幕" forstate:uicontrolstatenormal]; } else { _lockscreen = yes; [sender settitle:@"解开屏幕" forstate:uicontrolstatenormal]; } _lockorientation = _interorientation; } |
第2步：绕过强转
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- (void)interfaceorientation:(uiinterfaceorientation)orientation { [self isportrait]; //锁屏情况下 不旋转 if (!_lockscreen) { [self setinterorientation:orientation]; } |
第3步：针对 push 或 present 返回后
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- (void)viewwillappear:(bool)animated { if (_lockscreen) { //记录返回时的界面状态 [self setinterorientation:_lockorientation]; } else { [self isportrait]; } } |
5、 针对特定 uiviewcontroller 方向的支持
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-(uiinterfaceorientationmask)application:(uiapplication *)application supportedinterfaceorientationsforwindow:(uiwindow *)window { if ([nsstringfromclass([[self topviewcontroller] class]) isequaltostring:@"firstviewcontroller"]) { //横屏 return uiinterfaceorientationmasklandscaperight; } //竖屏 return uiinterfaceorientationmaskportrait; } |
最后的献上 github 代码，还有2个小的 bug ，有兴趣的朋友欢迎来探讨。
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持服务器之家。
原文链接：https://www.jianshu.com/p/5f82baaab740
