gps

问题 is there any way to detect a place with GPS coordinates ? (as much as possible without map ) for example check if longitude and latitude is equal or near to these : 44 35′25″n 104 42′55″w or 44.5903 -104.7153 then an alert pops up and display a message ! Thanks . 回答1: You can measure the distance between your "hardcoded" location and current users location with following: CLLocation *hardcoded_location = [[CLLocation alloc] initWithLatitude:latitude1 longitude:longitude1]; CLLocation *new

问题 I have to see if some GPS coordinates are in a circle that I create.when I say I am creating that circle I' refering to this: I have lat1, long1, my actual location and I want to test if there is any data surrounding this location but not far then 1km. I am trying to use circle inequation : (x2-a2)2+(y2-b2)2 <R2 where a=lat1, b=long1 and R=radius. I know that R=1km but how do I transform 1km into data that can be compared to GPS coordinates? and x, y are every value from a collection that are

问题 In my app, I've tried two ways of accessing location: a) Using LocationManager and GPS_PROVIDER. I accept location to be processed if it has accuracy 50 or less. App receives location however most of the time receives no location at all - while Google Maps when I start it to try it out gets my location constantly and more precise than my app. Here are parts of the source related to this: Start to listen to locations: // in service class, function to start listening for locations. // class

问题 I am working with geolocation in phonegap application. I get the location easily when High Accuracy and Battery saving mode is ON. But it gives error while working in GPS. Please help. I am stuck in it. I applied the timeout upto 60000 milliseconds. But it didnot work even then. The code is - function Geolocation(){} Geolocation.options = { maximumAge: 60000, timeout: 15000, enableHighAccuracy: true }; Geolocation.errorMessage = 'Unable to get location data. Ensure that the location services

问题 In my app I am trying to make it possible to calculate the distance a person walks. To do this I have created a LocationHelper class that should get me the current GeoPoint every 30 seconds or 10 meters. I already have a method that returns the distance in meters between two GeoPoints that I know works, because I have used it in a previous project. I also have an Activity called WalkActivity where I call the method getDistance() in LocationHelper and display it in a TextView that is updated

问题 The project objective is something like this: We would have a locomotive robot having on-board GPS on it. Now using that GPS we want to track the position of robot and trace it on android cellphone. (as they provide best interface with Google services) Not only that We even want to control the robot from android cellphone. Is it possible to send control signal from android cellphone to that robot so that robot can make a move according to control signal. How can we make a connection between

问题 I want to edit GPS tag and save new GPS latitude and longitude to JPEG. Ok I found a Sanselan Java library which lets to do it. There is an example how to write metadata WriteExifMetadataExample end I used changeExifMetadata(File jpegImageFile, File dst) method. It works but this example creates a new photo with new gps latitude/longitude. I would like to set new GPS values on the same photo, how can I do this ? Generally I want to create application similar to Picasa (photo viewer + google

问题 I recently made an Android application using eclipse. It is working perfectly in my emulator. But when I export my application using the Export Wizard on Eclipse it made outputs of .apk and certificate files, I copied it to my Android phone, but the map doesn't show, it only shows gray tiles. It has a function of displaying a Toast with current Latitude and Longitude. It's displaying on my emulator, but not in my phone. It also displays a Toast that checks if the device's GPS is active. It

问题 When my application is quit my GPS sensor keeps working or when I change activities my application crashes depending on my configuration (in the code below it crashes when I change activities or quit the application). How do I change my below activity so that when I quit the application the GPS sensor stops running but when I move to another activity it keeps running? Here is the key parts to my activity: public class InitialChoice extends Activity { LocationManager mlocManager;

问题 I´m trying on first fix do something. I just need one location after is gps fixed. I don´t know how to do it. I tried onLocationChanged, but is never called I tried onGpsStatusChanged and also is never called. Is there any option how do something on getting first location? public class CenyActivity extends FragmentActivity implements LocationListener, OnMapClickListener, GpsStatus.Listener{ @Override public void onGpsStatusChanged(int event) { if (event == GpsStatus.GPS_EVENT_STARTED) { Log.d