Retrieve position of a google maps v3 marker to Qt in a desktop app with QtWebKit
I'm building a Qt app with Python where you can point and click at a (google) map and get the coordinates of the location. The map is shown through a QWebView loading a simple HTML page and the user can create markers by clicking. Screenshot of the widget after clicking on the map.
However, I'm having trouble to retrieve the just-clicked location coordinates back to Qt (so that I can use them as variables -- and, for example, show them in the QLineEdits on the topleft corner above, as current location of the marker).
This is the relevant part of the HTML file:
<script type="text/javascript">
var map;
function initialize() {
var local = new google.maps.LatLng(-23.4,-40.3);
var myOptions = {
zoom: 5,
center: local,
mapTypeId: google.maps.MapTypeId.ROADMAP
}
map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);
google.maps.event.addListener(map, 'rightclick', function(event) {
placeMarker(event.latLng);
});
}
function placeMarker(location) {
var clickedLocation = new google.maps.LatLng(location);
var marker = new google.maps.Marker({
position: location,
map: map
});
map.setCenter(location);
}
function dummyTxt() {
return 'This works.';
}
</script>
I've been trying with evaluateJavaScript, but was not able to retrieve the coordinates. I tried to created a function to access the position with marker.getPosition(), but with no luck. The dummy below works though..
newplace = QWebView.page().mainFrame().evaluateJ开发者_StackOverflow社区avaScript(QString('dummyTxt()'))
>>> print newplace.toString()
This works.
Any suggestions on how to get the coordinates back to Qt?
Edit:
Here is the code that worked for me:
def update_geo(self):
# Capture coordinates of the last marker on the map.
mark = self.map.page().mainFrame().evaluateJavaScript('document.getElementById("markerlocation").value').toString()
# Convert string to list of floats, stripping parentheses.
marker = str(mark).strip('()').split(', ')
decimals = [float(c) for c in marker]
Full source in https://github.com/nelas/veliger/blob/master/veliger.py#L2374
I found a work around to make it work but I'm not pretty sure that it will be the right approach. Anyway, this is what I did:
Create a hidden input in the body section of your html document to save the position data of the marker:
<body> (...) <input id="locationData" type="hidden"> (...) </body>In the javascript code, save the position of the marker in the hidden input every time it's created:
function placeMarker(location) { (...) document.getElementById("locationData").value = marker.position; (...) }In your Qt code, read the value of the hidden input with the instruction:
webView->page()->mainFrame()->findFirstElement("#locationData").evaluateJavaScript("this.value").toString();
I hope it helps!
Source: http://opendocs.net/qt/4.6/webkit-formextractor.html
加载中,请稍侯......
精彩评论