IPHONE实景导航开发总结
1. 在摄像头捕获的画面上添加一个自定义的view。
使用iphoneSDK 3.1的新API：UIImagePickerController的新属性cameraOverView来添加一个自定义的view。
- - (IBAction)getCameraPicture: (id)sender {
- UIImagePickerController* picker = [[UIImagePickerController alloc] init];
- picker.delegate = self;
- picker.sourceType = UIImagePickerControllerSourceTypeCamera;
- //picker.allowsEditing = YES;
- picker.showsCameraControls = NO;//关闭默认的摄像设备
- //picker.toolbarHidden = YES;
- //设定图像缩放比例
- picker.cameraViewTransform = CGAffineTransformScale(picker.cameraViewTransform, 1.0, 1.0);
- //添加自定义信息层
- self.overView = [[OverlayViewConroller alloc] initWithNibName:@"OverlayViewConroller" bundle:nil WithCameraPicker:picker];
- overView.view.backgroundColor = [UIColor clearColor];//设定透明背景色
- picker.cameraOverlayView = overView.view;
- //打开摄像画面作为背景
- [self presentModalViewController:picker animated:YES];
- [picker release];
- }
- (IBAction)getCameraPicture: (id)sender {
UIImagePickerController* picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
picker.sourceType = UIImagePickerControllerSourceTypeCamera;
//picker.allowsEditing = YES;
picker.showsCameraControls = NO;//关闭默认的摄像设备
//picker.toolbarHidden = YES;
//设定图像缩放比例
picker.cameraViewTransform = CGAffineTransformScale(picker.cameraViewTransform, 1.0, 1.0);
//添加自定义信息层
self.overView = [[OverlayViewConroller alloc] initWithNibName:@"OverlayViewConroller" bundle:nil WithCameraPicker:picker];
overView.view.backgroundColor = [UIColor clearColor];//设定透明背景色
picker.cameraOverlayView = overView.view;
//打开摄像画面作为背景
[self presentModalViewController:picker animated:YES];
[picker release];
}
2. 在自定义的view上添加标志点图标。
一种方法是在view的- (void)drawRect:(CGRect)rect;方法里面添加图像的绘制。
另一种方法是新建一个按钮view，设定背景图片，利用addSubView的方法添加到当前view中，本应用中采用此方法。
3. 对动态添加的按钮绑定UIControlEventTouchUpInside事件关联
可以利用UIButton的方法 addTarget:self action:@selector(tagClick:) forControlEvents:UIControlEventTouchUpInside来绑定需要的事件。
- - (UIButton*)createButton:(CGFloat) x withY:(CGFloat) y withTitle:(NSString*) title withPercent:(CGFloat)percent {
- UIButton* btn = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, ballon.size.width * percent, ballon.size.height * percent)];
- [btn setCenter:CGPointMake(x, y)];
- btn.autoresizingMask = UIViewAutoresizingNone;
- [btn setBackgroundImage:ballon forState:UIControlStateNormal];
- [btn setTitle:title forState:UIControlStateNormal];
- [btn addTarget:self action:@selector(tagClick:) forControlEvents:UIControlEventTouchUpInside];
- return btn;
- }
- (UIButton*)createButton:(CGFloat) x withY:(CGFloat) y withTitle:(NSString*) title withPercent:(CGFloat)percent {
UIButton* btn = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, ballon.size.width * percent, ballon.size.height * percent)];
[btn setCenter:CGPointMake(x, y)];
btn.autoresizingMask = UIViewAutoresizingNone;
[btn setBackgroundImage:ballon forState:UIControlStateNormal];
[btn setTitle:title forState:UIControlStateNormal];
[btn addTarget:self action:@selector(tagClick:) forControlEvents:UIControlEventTouchUpInside];
return btn;
}
4. 点击view上的标记点，弹出描述详细情报的信息框，比如文字加上图片。
因为在iphone的应用中同时只能有一个窗体画面，所以只能采用弹出对话框来显示了，默认的对话框只能显示文字描述，要想显示图片，就需要改造对话框，方法是让类实现协议< UIAlertViewDelegate>，重写方法- (void) willPresentAlertView:(UIAlertView*) alertView ;在这个方法里添加UIImageView来显示图片，改变对话框的大小，以及按钮的位置。
- - (void)tagClick:(id)sender {
- //[picker takePicture];
- UIAlertView* infoView = [[UIAlertView alloc]
- initWithTitle:@"Info"
- message:@"some thing is done"
- delegate:self
- cancelButtonTitle:@"Close"
- otherButtonTitles:nil];
- [infoView show];
- [infoView release];
- }
- (void)tagClick:(id)sender {
//[picker takePicture];
UIAlertView* infoView = [[UIAlertView alloc]
initWithTitle:@"Info"
message:@"some thing is done"
delegate:self
cancelButtonTitle:@"Close"
otherButtonTitles:nil];
[infoView show];
[infoView release];
}
5. 在详细信息中播放视频
由于iphone未提供在任意控件内播放视频的功能，所以只能在详细表示画面添加视频播放的按钮，调用MPMoviePlayerController的play方法来播放视屏，MPMoviePlayerController的初始化方法使用initWithContentURL方法加载视频播放的路径URL
- - (void) playMovie {
- MPMoviePlayerController* mp = [[MPMoviePlayerController alloc] initWithContentURL:movieURL];
- if (mp) {
- self.moviePlayer = mp;
- [mp release];
- }
- [self.moviePlayer play];
- }
- (void) playMovie {
MPMoviePlayerController* mp = [[MPMoviePlayerController alloc] initWithContentURL:movieURL];
if (mp) {
self.moviePlayer = mp;
[mp release];
}
[self.moviePlayer play];
}
6. 加载本地文件的路径URL
由于iphone在运行时有一个临时的运行环境，需要使用[NSBundle mainBundle]取得一个主Bundle，使用NSBundle的方法pathForResource:@"Movie" ofType:@"m4v"来生成一个本地运行时的文件路径。
- - (NSURL*)localMovieURL {
- if (self.movieURL == nil) {
- NSBundle* bundle = [NSBundle mainBundle];
- if (bundle) {
- NSString* moviePath = [bundle pathForResource:@"Movie" ofType:@"m4v"];
- if (moviePath) {
- self.movieURL = [NSURL fileURLWithPath:moviePath];
- }
- }
- }
- return self.movieURL;
- }
- (NSURL*)localMovieURL {
if (self.movieURL == nil) {
NSBundle* bundle = [NSBundle mainBundle];
if (bundle) {
NSString* moviePath = [bundle pathForResource:@"Movie" ofType:@"m4v"];
if (moviePath) {
self.movieURL = [NSURL fileURLWithPath:moviePath];
}
}
}
return self.movieURL;
}
7. 让画面中的按钮view随拍摄方位的变化而移动
让画面中的view的移动，是通过设定UIButton的属性transform来实现的，需要使用[UIView beginAnimations:nil context:nil];启动一个动画环境，设定动画的动作时间以及延迟，通过[UIView commitAnimations];提交动画，transform是通过CGAffineTransformMakeTranslation(x, y)的类来生成，其中x为x方向需要移动的相对距离，y为y方向上需要移动的相对距离。
- - (void)moveButton:(UIButton*)button withOffsetX:(NSInteger)x andOffsetY:(NSInteger)y {
- [UIView beginAnimations:nil context:nil];
- [UIView setAnimationDuration:0.0];
- [UIView setAnimationDelay:0.0];
- CGAffineTransform transform = CGAffineTransformMakeTranslation(x, y);
- button.transform = transform;
- [UIView commitAnimations];
- }
- (void)moveButton:(UIButton*)button withOffsetX:(NSInteger)x andOffsetY:(NSInteger)y {
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:0.0];
[UIView setAnimationDelay:0.0];
CGAffineTransform transform = CGAffineTransformMakeTranslation(x, y);
button.transform = transform;
[UIView commitAnimations];
}
8. 让画面中的按钮view随距离远近而改变按钮view大小
取得当前按钮view 的frame.size，重新设定其width和height，把frame设定回按钮view就可以改变其大小了，可能有通过动画实现的方法，我暂时还未发现。
- - (void)scaleButton:(UIButton*)button withOffsetX:(CGFloat)x andOffsetY:(CGFloat)y {
- CGRect frame = button.frame;
- frame.size.width = x;
- frame.size.height = y;
- button.frame = frame;
- }
- (void)scaleButton:(UIButton*)button withOffsetX:(CGFloat)x andOffsetY:(CGFloat)y {
CGRect frame = button.frame;
frame.size.width = x;
frame.size.height = y;
button.frame = frame;
}
9. 使用GPS设定其精度并，取得方位（经度，纬度），方向的数据
使用CLLocationManager来取得当前的GPS经度，纬度，方位的数据，首先初始化CLLocationManager，设定其精度，更新回调，更新的距离筛选，通过方法startUpdatingHeading来开启方向的更新，通过方法startUpdatingLocation来开启方位的更新。
- //初始化方位类
- self.localManager = [[CLLocationManager alloc] init];
- localManager.delegate = self;
- //开启电子罗盘
- if (localManager.headingAvailable)
- [localManager startUpdatingHeading];//启动
- //开启GPS
- if(localManager.locationServicesEnabled) {
- localManager.desiredAccuracy = kCLLocationAccuracyBest;//设定为最佳精度
- localManager.distanceFilter = 5.0f;//响应位置变化的最小距离(m)
- [localManager startUpdatingLocation];
- }
//初始化方位类
self.localManager = [[CLLocationManager alloc] init];
localManager.delegate = self;
//开启电子罗盘
if (localManager.headingAvailable)
[localManager startUpdatingHeading];//启动
//开启GPS
if(localManager.locationServicesEnabled) {
localManager.desiredAccuracy = kCLLocationAccuracyBest;//设定为最佳精度
localManager.distanceFilter = 5.0f;//响应位置变化的最小距离(m)
[localManager startUpdatingLocation];
}
10. 取得方位（经度，纬度），方向的数据更新回调值
通过实现协议CLLocationManagerDelegate来取得数据更新的回调，其中(BOOL)locationManagerShouldDisplayHeadingCalibration:(CLLocationManager *)manager是方向更新的过滤器，- (void)locationManager:(CLLocationManager *)manager didUpdateHeading:(CLHeading *)newHeading 是方向更新的回调方法，可以通过newHeading.magneticHeading来取得当前的方向角度（正北方向为0度）。
- (void)locationManager:(CLLocationManager *)manager
didUpdateToLocation:(CLLocation *)newLocation
fromLocation:(CLLocation *)oldLocation为方位（经度，纬度）的更新回调，可以通过newLocation.horizontalAccuracy取得当前定位精度圆半径，newLocation.coordinate.latitude取得纬度数据，newLocation.coordinate.longitude取得精度数据，而- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error是GPS初始化失败的回调，应为开启GPS需要得到用户的许可，没有许可就无法正常开启。
- //方位变化的回调函数
- - (void)locationManager:(CLLocationManager *)manager didUpdateHeading:(CLHeading *)newHeading {
- //初始化方位
- if ([fileLoader isKindOfClass:[TestLoader class]]) {
- if (localDir == 0) {
- baseDir = newHeading.magneticHeading;
- localDir = newHeading.magneticHeading;
- }
- }
- float newlocalDir = newHeading.magneticHeading;
- //当变化超过一定范围，刷新标志显示
- if (abs(newlocalDir - localDir) > FLASH_DEGREE) {
- localDir = newlocalDir;
- [self computer];
- }
- //更新指南针方向
- [overlayView updateHeading:newHeading];
- }
- //方位变化的回调函数
- - (BOOL)locationManagerShouldDisplayHeadingCalibration:(CLLocationManager *)manager {
- return YES;
- }
- //GPS位置变化的回调
- - (void)locationManager:(CLLocationManager *)manager
- didUpdateToLocation:(CLLocation *)newLocation
- fromLocation:(CLLocation *)oldLocation {
- self.local = newLocation;
- //更新经纬度表示值
- [overlayView updateLocation:self.local];
- if ([fileLoader isKindOfClass:[GPSLoader class]]) {
- [fileLoader computerDis:allTags andLocal:local];
- //重新计算当前标志点的位置
- [self computer];
- }
- //关闭定位
- //[localManager stopUpdatingLocation];
- }
- //GPS初始化失败
- - (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error {
- NSLog(@"Location manager error: %@", [error description]);
- }
//方位变化的回调函数
- (void)locationManager:(CLLocationManager *)manager didUpdateHeading:(CLHeading *)newHeading {
//初始化方位
if ([fileLoader isKindOfClass:[TestLoader class]]) {
if (localDir == 0) {
baseDir = newHeading.magneticHeading;
localDir = newHeading.magneticHeading;
}
}
float newlocalDir = newHeading.magneticHeading;
//当变化超过一定范围，刷新标志显示
if (abs(newlocalDir - localDir) > FLASH_DEGREE) {
localDir = newlocalDir;
[self computer];
}
//更新指南针方向
[overlayView updateHeading:newHeading];
}
//方位变化的回调函数
- (BOOL)locationManagerShouldDisplayHeadingCalibration:(CLLocationManager *)manager {
return YES;
}
//GPS位置变化的回调
- (void)locationManager:(CLLocationManager *)manager
didUpdateToLocation:(CLLocation *)newLocation
fromLocation:(CLLocation *)oldLocation {
self.local = newLocation;
//更新经纬度表示值
[overlayView updateLocation:self.local];
if ([fileLoader isKindOfClass:[GPSLoader class]]) {
[fileLoader computerDis:allTags andLocal:local];
//重新计算当前标志点的位置
[self computer];
}
//关闭定位
//[localManager stopUpdatingLocation];
}
//GPS初始化失败
- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error {
NSLog(@"Location manager error: %@", [error description]);
}
11. 计算GPS两点间的距离的算法
一种方法通过CLLocation的实例方法getDistanceFrom方法计算两点间的距离（m），
如果没有API可用，可以通过积分的方式利用三角定律估算出两点的直线距离。
- CLLocation* location1 = [[CLLocation alloc] initWithLatitude:latin1 longitude:lonin1];
- CLLocation* location2 = [[CLLocation alloc] initWithLatitude:latin2 longitude:lonin2];
- return [location1 getDistanceFrom:location2];
CLLocation* location1 = [[CLLocation alloc] initWithLatitude:latin1 longitude:lonin1]; CLLocation* location2 = [[CLLocation alloc] initWithLatitude:latin2 longitude:lonin2]; return [location1 getDistanceFrom:location2];
12. 计算GPS两点间的方向角度的算法
以其中一点作为原点，经过此原点的经度线作为y坐标轴，纬度线作为x坐标轴，在这个坐标系中利用atan2f三角函数取得相对于y轴夹角，再加上对应的偏移量，就可以取得相当于y轴的正方向（正北方向）的角度。
- //计算GPS两点间的经度距离
- + (CGFloat) calcuLoninM:(CGFloat) latin1 withLonin:(CGFloat) lonin1
- withDisLatin:(CGFloat) latin2 withDisLonin:(CGFloat) lonin2 {
- CGFloat retval = 0.0;
- CGFloat latin = latin1;
- CGFloat latinStep = (latin1 - latin2) / MAX_LENGTH;
- CGFloat loninStep = (lonin1 - lonin2) / MAX_LENGTH;
- if (loninStep < 0) {
- loninStep = -1.0 * loninStep;
- }
- for (int i = 0 ; i < MAX_LENGTH; i++) {
- retval += EARTH_RADIUS * [GPSHelp toRadians:loninStep] * cos([GPSHelp toRadians:latin]);
- latin += latinStep;
- }
- return retval;
- }
- //计算GPS两点间的纬度距离
- + (CGFloat) calcuLatinM:(CGFloat) latin1 withLonin:(CGFloat) lonin1
- withDisLatin:(CGFloat) latin2 withDisLonin:(CGFloat) lonin2 {
- CGFloat angle = latin1 - latin2;
- if (angle < 0) {
- angle = -1.0 * angle;
- }
- return [GPSHelp toRadians:angle] * EARTH_RADIUS;
- }
- //角度转弧度
- + (CGFloat)toRadians:(CGFloat)degree {
- return degree / 180.0 * M_PI;
- }
- //弧度转角度
- + (CGFloat)toDegrees:(CGFloat)radian {
- return radian / M_PI * 180.0;
- }
- @end
- @implementation GPSHelp
- //计算GPS两点间的角度（正北方向为0度）
- + (CGFloat) calcuAngle:(CGFloat) latin1 withLonin:(CGFloat) lonin1
- withDisLatin:(CGFloat) latin2 withDisLonin:(CGFloat) lonin2 {
- CGFloat loninM = [GPSHelp calcuLoninM:latin1 withLonin:lonin1 withDisLatin:latin2 withDisLonin:lonin2];
- CGFloat latinM = [GPSHelp calcuLatinM:latin1 withLonin:lonin1 withDisLatin:latin2 withDisLonin:lonin2];
- CGFloat radian = atan2f(loninM, latinM);
- if (lonin2 >= lonin1) {
- if (latin2 >= latin1) {
- ;
- } else {
- radian = M_PI - radian;
- }
- } else {
- if (latin2 >= latin1) {
- radian = 2.0 * M_PI - radian;;
- } else {
- radian = M_PI + radian;
- }
- }
- return [GPSHelp toDegrees:radian];
- }
//计算GPS两点间的经度距离
+ (CGFloat) calcuLoninM:(CGFloat) latin1 withLonin:(CGFloat) lonin1
withDisLatin:(CGFloat) latin2 withDisLonin:(CGFloat) lonin2 {
CGFloat retval = 0.0;
CGFloat latin = latin1;
CGFloat latinStep = (latin1 - latin2) / MAX_LENGTH;
CGFloat loninStep = (lonin1 - lonin2) / MAX_LENGTH;
if (loninStep < 0) {
loninStep = -1.0 * loninStep;
}
for (int i = 0 ; i < MAX_LENGTH; i++) {
retval += EARTH_RADIUS * [GPSHelp toRadians:loninStep] * cos([GPSHelp toRadians:latin]);
latin += latinStep;
}
return retval;
}
//计算GPS两点间的纬度距离
+ (CGFloat) calcuLatinM:(CGFloat) latin1 withLonin:(CGFloat) lonin1
withDisLatin:(CGFloat) latin2 withDisLonin:(CGFloat) lonin2 {
CGFloat angle = latin1 - latin2;
if (angle < 0) {
angle = -1.0 * angle;
}
return [GPSHelp toRadians:angle] * EARTH_RADIUS;
}
//角度转弧度
+ (CGFloat)toRadians:(CGFloat)degree {
return degree / 180.0 * M_PI;
}
//弧度转角度
+ (CGFloat)toDegrees:(CGFloat)radian {
return radian / M_PI * 180.0;
}
@end
@implementation GPSHelp
//计算GPS两点间的角度（正北方向为0度）
+ (CGFloat) calcuAngle:(CGFloat) latin1 withLonin:(CGFloat) lonin1
withDisLatin:(CGFloat) latin2 withDisLonin:(CGFloat) lonin2 {
CGFloat loninM = [GPSHelp calcuLoninM:latin1 withLonin:lonin1 withDisLatin:latin2 withDisLonin:lonin2];
CGFloat latinM = [GPSHelp calcuLatinM:latin1 withLonin:lonin1 withDisLatin:latin2 withDisLonin:lonin2];
CGFloat radian = atan2f(loninM, latinM);
if (lonin2 >= lonin1) {
if (latin2 >= latin1) {
;
} else {
radian = M_PI - radian;
}
} else {
if (latin2 >= latin1) {
radian = 2.0 * M_PI - radian;;
} else {
radian = M_PI + radian;
}
}
return [GPSHelp toDegrees:radian];
}
13. 根据GPS两点间的方向角度以及当前电子罗盘的方向角度算出对应的屏幕的2D坐标值
假设当前的可见角度范围是-90到+90之间，首先计算出电子罗盘的方向角度和GPS两点间的方向角度的角度差，再通过角度格式化成-90到+90之间的一个数值，再计算出这个角度相对于90度的比例，乘上屏幕中心点的x坐标，就可以得到此点对应于当前屏幕的x坐标值。
14. 根据两点间的距离算出对应屏幕的2D坐标值及大小
假设可见的最远距离是200m，让200m距离内的所有标志点显示在屏幕的下半部分，也就是说在>屏幕中心点的y坐标<最大的y坐标的范围内，距离越近的点显示在越靠近屏幕最下方的地方，标记大小也越接近原始大小。根据两点间的距离占200m的比例，计算出y坐标值。大小的计算类同。此算法显示的效果不是很真实，有待继续研究。