Ascertain Google Streetview function existence
Is there a way of ascertaining if a Google Streetview panorama is avai开发者_运维知识库lable from an Android application (i.e. using Java).
No alternatives seem to exist for PHP or Python or other server-side technologies.
The impact of calling Google Streetview where no panorama exists is simply a black screen and a "spinning thing".
I created a little hack for this. :)
strings.xml
<string name="html_streetview"> <![CDATA[
<html>
<head>
<script src="http://maps.google.com/maps/api/js?v=3&sensor=false" type="text/javascript"></script>
</head>
<body>
<script type="text/javascript">
Android.echo();
var testPoint = new google.maps.LatLng(%1$s, %2$s,true);
var svClient = new google.maps.StreetViewService();
svClient.getPanoramaByLocation(testPoint, 50,function (panoramaData, status) {
if (status == google.maps.StreetViewStatus.OK) {
Android.hasStreetview();
} else {
Android.hasNotStreetview();
}
});
</script>
</body>
</html>
]]>
</string>
now add a button for streetview on the activity and put this following code into the onclick method:
if (webView == null) {
webView = new WebView(this);
webView.setVisibility(View.INVISIBLE);
webView.getSettings().setJavaScriptEnabled(true);
webView.addJavascriptInterface(new JavascriptCheck(this), "Android");
webView.setWebViewClient(new WebViewClient() {
public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
Toast.makeText(this, "Streetview loading", Toast.LENGTH_SHORT).show();
super.onReceivedError(view, errorCode, description, failingUrl);
}
});
}
Toast.makeText(this, "Streetview loading", Toast.LENGTH_SHORT).show();
webView.loadDataWithBaseURL(baseurl,
getString(R.string.html_streetview, latitude, longitude), "text/html", "UTF-8", baseurl);
And now the inner Class of the activity:
public class JavascriptCheck {
private final Context context;
public JavascriptCheck(Context context) {
this.context = context;
}
public void echo() {
Log.d("JavascriptChecker", "javascript called");
}
public void hasStreetview() {
pushStreetviewState(true);
}
public void hasNotStreetview() {
pushStreetviewState(false);
}
private void pushStreetviewState(final boolean hasStreetview) {
Log.d("JavascriptChecker", hasStreetview);
// TODO do your stuff needed here
}
}
this a a rather bad workaround but probably can help. :)
Thanks a bunch Alos and steemcb, I was stuck with street view showing the wrong property or a blank screen. I hope google comes out with a native android SDK, until then both your codes ROX!!
I had to make a few adjustments before I could use the code. Here is my implementation.
strings.xml
<string formatted="false" name="html_streetview">
<html>
<head>
<script src=\"http://maps.google.com/maps?file=api&amp;v=2&amp;sensor=false\" type=\"text/javascript\"/>
</head>
<body>
<script type=\"text/javascript\">
var testPoint = new GLatLng(%1$s, %2$s);
var svClient = new GStreetviewClient();
svClient.getNearestPanoramaLatLng(testPoint,function(camera){
if (camera !== null){
lat2 = camera.lat();
lon2 = camera.lng();
lat1 = testPoint.lat();
lon1 = testPoint.lng();
dLon = lon1 - lon2;
y = Math.sin(dLon) * Math.cos(lat2);
x = Math.cos(lat1) * Math.sin(lat2) - Math.sin(lat1) * Math.cos(lat2) * Math.cos(dLon);
var bearing = Math.atan2(y, x) * (180 / Math.PI);
//had to get rid of this line it was causing formatting exceptions
// I moved this logic to the inner class
//bearing = (bearing + 180) % 360;
Android.setStreetViewAngle(bearing);
}
//had trouble with bearing taking long to calculate and end up with 0.0 value in the uri. So I put it in here after when bearing is calculated. Not pretty.. but it works for me
svClient.getNearestPanoramaLatLng(testPoint, function (nearest) {
if ((nearest !== null) && (testPoint.distanceFrom(nearest) <= 100)) {
Android.hasStreetview(true);
}
else {
Android.hasStreetview(false);
}
});
});
</script>
</body>
</html>
</string>
Private Inner Class
private final Context context;
private double bearing;
public JavascriptCheck(Context context) {
this.context = context;
}
public void hasStreetview(boolean hasStreetview) {
if (hasStreetview) {
String uri = "google.streetview:cbll=" + propDetailInfo.getLatitude() + "," + propDetailInfo.getLongitude() +
"&cbp=1,"+ bearing + ",,1,1.0&mz=14";
Utils.printDebug("URI: " + uri);
Intent streetView = new Intent(Intent.ACTION_VIEW, Uri.parse(uri));
startActivity(streetView);
} else {
Toast.makeText(context, "Sorry Streetview not available for this address", Toast.LENGTH_LONG).show();
}
}
public void setStreetViewAngle(double bearing){
bearing = (bearing + 180) % 360;
this.bearing = bearing;
}
public void toast(String part) {
Toast.makeText(context, part, Toast.LENGTH_SHORT).show();
}
}
Just to further on the excellent answer from alos, here is a script which will return you the angle needed so that streetview will launch pointed at the correct coordinates:
<string name="html_streetview_bearing"> <![CDATA[
<html>
<head>
<script src="http://maps.google.com/maps/api/js?v=3&sensor=false" type="text/javascript"></script>
</head>
<body>
<script type=\"text/javascript\">
var testPoint = new google.maps.LatLng(%1$s, %2$s,true);
var svClient = new google.maps.StreetViewService();
svClient.getPanoramaByLocation(testPoint,100,function (camera, status) {
if(camera!=null) {
var location = camera.location;
var latLng = location.latLng;
lat2 = latLng.lat();
lon2 = latLng.lng();
lat1 = testPoint.lat();
lon1 = testPoint.lng();
var dLon = lon1 - lon2;
var y = Math.sin(dLon) * Math.cos(lat2);
var x = Math.cos(lat1) * Math.sin(lat2) - Math.sin(lat1) * Math.cos(lat2) * Math.cos(dLon);
var bearing = Math.atan2(y, x) * (180 / Math.PI);
Android.setStreetviewAngle(bearing);
}
}
);
</script>
</body>
</html>
]]>
</string>
Note: The return value needs to be altered so that
bearing = (bearing + 180) % 360;
to give you the correct final value. I do this in native code.
UPDATED ANSWER: Now working on Android 3.0 and greater.
A way to do that would be to use Google Street View Image API to check whether Google Street View exist or not.
https://developers.google.com/maps/documentation/streetview/
It returns an image with a different file size when Street View at a particular co-ordinates exist,than when it doesn't
http://maps.googleapis.com/maps/api/streetview?size=400x400&location=40.720032,%20-73.988354&fov=90&heading=235&pitch=10&sensor=false
You can compare these images and check if it exist or not.
加载中,请稍侯......
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