我正在尝试在谷歌地图上显示多个标记,但我似乎只显示最后一个标记。原因是标记在 for 循环中被覆盖。我创建了一个将存储标记的ArrayList,但我不知道如何将其添加到谷歌地图中。
折线库包含一个名为addAll
的方法,该方法添加了折线的数组列表,但标记没有这样的东西。谁能建议一种在地图上添加多个标记的方法?
public void mapForGPS(GoogleMap googleMap) {
mMap = googleMap;
double[] firstCoords;
double[] lastCoords;
double[] receivedDataArray;
double latitude;
double longitude;
double[] firstSetOfCoordinatesFromArray;
double[] lastSetOfCoordinatesFromArray;
double[] tempCoordinatesArray;
String[] tempDurationAndTimeArray;
String time;
GpsData gpsDataObj;
String[] dataForOneGreenDot;
String[] arrayOfGreenDots = new String[3];
// this will store coordinates for one iteration of a selected day
ArrayList<LatLng> coordList = new ArrayList<LatLng>();
ArrayList<String[]> arrayListOfGreenDots = new ArrayList<String[]>();
// clear polyline array that has coordinates form previous iteration
coordList.clear();
// clears all the markers on the map for the next iteration
mMap.clear();
// loop through JSON array of coordinates and assign data into a coordinates array with an
// object of Latitude and Longitude
for (int i = 0; i <= arrayOfGpsData.size() - 1; i++) {
gpsDataObj = arrayOfGpsData.get(i);
tempCoordinatesArray = gpsDataObj.getArrayOfDoubles();
tempDurationAndTimeArray = gpsDataObj.getArrayOfStrings();
latitude = tempCoordinatesArray[0];
longitude = tempCoordinatesArray[1];
coordList.add(new LatLng(latitude,longitude));
time = tempDurationAndTimeArray[0];
String latString = String.valueOf(latitude);
String longString = String.valueOf(longitude);
arrayOfGreenDots[0] = latString;
arrayOfGreenDots[1] = longString;
arrayOfGreenDots[2] = time;
arrayListOfGreenDots.add(arrayOfGreenDots);
}
// if there was a previous polyline on the map, clear it
if(polylineGPS != null){
polylineGPS.remove();
}
// add coordinates to a polylineGPS object
options = new PolylineOptions().addAll(coordList).width(5).color(Color.BLUE).geodesic(true);
polylineGPS = mMap.addPolyline(options);
// if user selected date in date-time picker then marker will point to
// first set of coordinates in the coordinatesArray and the map will zoom in on that point
if(!arrayOfGpsData.isEmpty())
{
double[] coordinatesFromFirstIndex = new double[2];
String[] timeAndDurationFromFirstIndex = new String[2];
double[] coordinatesFromLastIndex = new double[2];
String[] timeAndDurationFromLastIndex = new String[2];
GpsData objectDataFromFirstIndex = new GpsData(coordinatesFromFirstIndex, timeAndDurationFromFirstIndex);
GpsData objectDataFromLastIndex = new GpsData(coordinatesFromLastIndex, timeAndDurationFromLastIndex);
// get first set of coordinates from array as starting position
objectDataFromFirstIndex = arrayOfGpsData.get(0);
firstSetOfCoordinatesFromArray = objectDataFromFirstIndex.getArrayOfDoubles();
// get last set of coordinates from array as ending position
objectDataFromLastIndex = arrayOfGpsData.get(arrayOfGpsData.size() - 1);
lastSetOfCoordinatesFromArray = objectDataFromLastIndex.getArrayOfDoubles();
//timeAndDurationFromFirstIndex = objectDataFromFirstIndex.getArrayOfStrings();
// place marker for starting position
LatLng firstLocationPointOfDevice = new LatLng(firstSetOfCoordinatesFromArray[0], firstSetOfCoordinatesFromArray[1]);
mMap.addMarker(new MarkerOptions().position(firstLocationPointOfDevice).icon((BitmapDescriptorFactory.fromResource(R.drawable.blue_marker))).title("Starting Location"));
// place marker for ending position
LatLng lastLocationPointOfDevice = new LatLng(lastSetOfCoordinatesFromArray[0], lastSetOfCoordinatesFromArray[1]);
mMap.addMarker(new MarkerOptions().position(lastLocationPointOfDevice).icon(BitmapDescriptorFactory.fromResource(R.drawable.pink_marker)).title("Ending Location"));
// zoom in on first set of coordinates form coordinatesArray
mMap.moveCamera(CameraUpdateFactory.newLatLng(firstLocationPointOfDevice));
// camera zoom in position
mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(firstLocationPointOfDevice, 10));
List<Marker> markers = new ArrayList<Marker>();
// adding markers to array list
for(int k = 0; k <= arrayListOfGreenDots.size() - 1; k++){
dataForOneGreenDot = arrayListOfGreenDots.get(k);
double latSingle = Double.parseDouble(dataForOneGreenDot[0]);
double longSingle = Double.parseDouble(dataForOneGreenDot[1]);
String timeSingle = dataForOneGreenDot[2];
//drawMarker(latSingle, longSingle, timeSingle);
LatLng greenDot = new LatLng(latSingle, longSingle);
marker = mMap.addMarker(new MarkerOptions().position(greenDot).icon(BitmapDescriptorFactory.fromResource(R.drawable.green_dot)).title(timeSingle));
markers.add(marker);
}
}
// if user did not select any date from date time picker, then by default the map will zoom on vancouver
else if(arrayOfGpsData.isEmpty())
{
// default location if no date is selected
LatLng defaultLocation = new LatLng(49.2827, -123.1207);
mMap.moveCamera(CameraUpdateFactory.newLatLng(defaultLocation));
mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(defaultLocation, 10));
}
}
我真的不知道为什么这个问题被否决了,因为它解决了没有即时答案的合法问题。
不过,我找到了解决方案:
for (int i = 0; i <= arrayOfGpsData.size() - 1; i++) {
gpsDataObj = arrayOfGpsData.get(i);
tempCoordinatesArray = gpsDataObj.getArrayOfDoubles();
tempDurationAndTimeArray = gpsDataObj.getArrayOfStrings();
latitude = tempCoordinatesArray[0];
longitude = tempCoordinatesArray[1];
coordList.add(new LatLng(latitude,longitude));
time = tempDurationAndTimeArray[0];
mMap.addMarker(new MarkerOptions().position(new LatLng(latitude,longitude))
.icon(BitmapDescriptorFactory.fromResource(R.drawable.green_dot_6px))
.title(time)
);
}
当我遍历arrayOfGpsData
并将纬度和长度分配给我的LatLng
对象时,我会立即向该LatLng
添加一个带有时间戳的标记。
我希望这对将来的某人有所帮助:D