Delphi FMX MapView - 删除所有标记

Question

I have TMapView and placed some TMapMarkerDescriptors on it using MapView1.AddMarker(...), but how I can clear map (remove all placed marers) from it ?

I cant find something as MapView.Clear in documentation.

Answer 1

okay this works fine

var
   mar : array of  TMapMarker;

procedure TForm1.clear_markers;
var
i:integer;
begin
 if high(mar) > -1 then
  for i:=0 to high(mar) do
    if Assigned(mar[i]) then
     mar[i].Remove;

setlength(mar,0);
end;

Markers was placed by this code in loop. Variables loc and s are loaded from database

setlength(mar,length(mar)+1);
Descr := TMapMarkerDescriptor.Create(loc, s);
mar[high(mar)]:=MapView1.AddMarker(Descr);

Answer 2

It appears that you have to remove each marker individually as far as I can tell, which means you'll have to store references to the TMapMarker objects you've created. TMapMarker (the result of the MapView1.AddMarker call) has two methods. "Remove" removes the marker from the map, while "DisposeOf" will remove the marker from the map and free the TMapMarker object.