Question

我遇到了如何在Arraylist上添加addMarker的问题。我在for循环中使用createMarker来添加值。

try:
    employee = float(raw_input('Employee code number or 0 for guest: ') or 0.0)
except ValueError:
    print "Nice try buddy"
    print "Welcome BIG_OLD_BUDDY"

问题在于，当调用createMarker时，标记只会替换它在Arraylist上的值。我想要的是在[0,0,0,0]中添加arraylist中的标记..我该如何实现？

    self.user = self.pool?.currentUser()

    let mfaOptions = AWSCognitoIdentityUserMFAOption()

    mfaOptions.attributeName = "email"
    mfaOptions.deliveryMedium = AWSCognitoIdentityProviderDeliveryMediumType.email

    let settings = AWSCognitoIdentityUserSettings()
    settings.mfaOptions?.append(mfaOptions)


    self.user!.setUserSettings(settings).continueWith( executor: AWSExecutor.mainThread(), block: { (task: AWSTask!) -> Void in

        print(task.debugDescription)

        if let error = task.error as NSError? {
            print("error")
        } else {
            print("updated 2 factor")
        }


    })

Answer 1

它不会覆盖某个值，而是替换整个列表。

不要制作新的清单。让方法创建并返回。

public MarkerOptions createMarker(Double latitude, final Double longitude, String Plate_num) {

    // list = new ArrayList<>(); // Don't do this

    BitmapDescriptor image = BitmapDescriptorFactory.fromResource(R.drawable.bus);

   return new MarkerOptions()
            .position(new LatLng(latitude, longitude))
            .title("Plate No.")
            .snippet(Plate_num)
            .icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_BLUE)));
}

...

onResponse( ... ) {
    ...
    String lng = String.valueOf(longiString);

    MarkerOptions opts = createMarker(d, d2, plate_num);
    Marker m = mMapFragment.addMarker(opts);
    list.add(m);
}

如何正确地在Arraylist上的GoogleMap上添加addMarker

1 个答案: