在TWebBrowser（Google地圖）中顯示位置，而無需單擊按鈕

Question

如何在Google Maps中顯示位置，而無需單擊Delphi / Windows應用程序中的按鈕？ 當用戶單擊“客戶”表單上的“顯示位置”按鈕時，我試圖傳遞一個地址。 當前，如果用戶單擊“顯示位置”按鈕，則會傳遞地址，但是在打開ViewMaps表單時不會顯示該位置。 但是，一旦顯示了ViewMaps（TWebBrowser）表單，並在“備注”框中顯示了“ 1 Infinite Loop，Cupertino，CA 95014”地址，用戶可以單擊“ GoToAddressBtn”按鈕，然后將顯示位置。

那么，如何在用戶不必單擊ViewMaps表單上的“ GoToAddressBtn”按鈕的情況下，在Google地圖上顯示該位置呢？

   implementation

Uses ShredMain, ActiveX;

{$R *.dfm}

const
HTMLStr: AnsiString =
'<html> '+
'<head> '+
'<meta name="viewport" content="initial-scale=1.0, user-scalable=yes" /> '+
//'<meta http-equiv="X-UA-Compatible" content="IE=edge" />'+
'<script type="text/javascript" src="http://maps.google.com/maps/api/js?v=3"></script> '+
'<script type="text/javascript"> '+
''+
''+
'  var geocoder; '+
'  var map;  '+
//'  var address;  '+
'  var trafficLayer;'+
'  var bikeLayer;'+
'  var markersArray = [];'+
''+
''+
'  function initialize() { '+
'    geocoder = new google.maps.Geocoder();'+
'    var latlng = new google.maps.LatLng(40.714776,-74.019213); '+
//'    var address = "San Diego, CA";'+
'    var myOptions = { '+
'      zoom: 11, '+
'      center: latlng, '+
'      mapTypeId: google.maps.MapTypeId.ROADMAP '+
'    }; '+
'    map = new google.maps.Map(document.getElementById("map_canvas"), myOptions); '+
'    trafficLayer = new google.maps.TrafficLayer();'+
'    bikeLayer = new google.maps.BicyclingLayer();'+
'    map.set("streetViewControl", false);'+
'  } '+
''+
''+
'  function codeAddress(address) { '+
'    if (geocoder) {'+
'      geocoder.geocode( { address: address}, function(results, status) { '+
'        if (status == google.maps.GeocoderStatus.OK) {'+
'          map.setCenter(results[0].geometry.location);'+
'          PutMarker(results[0].geometry.location.lat(), results[0].geometry.location.lng(), results[0].geometry.location.lat()+","+results[0].geometry.location.lng());'+
'        } else {'+
'          alert("Geocode was not successful for the following reason: " + status);'+
'        }'+
'      });'+
'    }'+
'  }'+
''+
''+
'  function GotoLatLng(Lat, Lang) { '+
'   var latlng = new google.maps.LatLng(Lat,Lang);'+
'   map.setCenter(latlng);'+
'   PutMarker(Lat, Lang, Lat+","+Lang);'+
'  }'+
''+
''+
'function ClearMarkers() {  '+
'  if (markersArray) {        '+
'    for (i in markersArray) {  '+
'      markersArray[i].setMap(null); '+
'    } '+
'  } '+
'}  '+
''+
'  function PutMarker(Lat, Lang, Msg) { '+
'   var latlng = new google.maps.LatLng(Lat,Lang);'+
'   var marker = new google.maps.Marker({'+
'      position: latlng, '+
'      map: map,'+
'      title: Msg+" ("+Lat+","+Lang+")"'+
'  });'+
' markersArray.push(marker); '+
'  }'+
''+
''+
'  function TrafficOn()   { trafficLayer.setMap(map); }'+
''+
'  function TrafficOff()  { trafficLayer.setMap(null); }'+
''+''+
'  function BicyclingOn() { bikeLayer.setMap(map); }'+
''+
'  function BicyclingOff(){ bikeLayer.setMap(null);}'+
''+
'  function StreetViewOn() { map.set("streetViewControl", true); }'+
''+
'  function StreetViewOff() { map.set("streetViewControl", false); }'+
''+
''+'</script> '+
'</head> '+
'<body onload="initialize()"> '+
'  <div id="map_canvas" style="width:100%; height:100%"></div> '+
'</body> '+
'</html> ';

procedure TViewMaps.Timer1Timer(Sender: TObject);
var
  aStream: TMemoryStream;
begin
  Timer1.Enabled:= False; //Disable timer so it doesn't fire again
  WebBrowser1.Navigate('about:blank');
  if Assigned(WebBrowser1.Document) then
  begin
    aStream := TMemoryStream.Create;
    try
       aStream.WriteBuffer(Pointer(HTMLStr)^, Length(HTMLStr));
       //aStream.Write(HTMLStr[1], Length(HTMLStr));
       aStream.Seek(0, soFromBeginning);
       MemoAddress.Lines.Clear;
       MemoAddress.Lines.Add('1 Infinite Loop. Cupertino, CA 95014');
       address := MemoAddress.Lines.Text;
       address := StringReplace(StringReplace(Trim(address), #13, ' ', [rfReplaceAll]), #10, ' ', [rfReplaceAll]);
       //HTMLWindow2.execScript(Format('codeAddress(%s)',[QuotedStr(address)]), 'JavaScript');
       (WebBrowser1.Document as IPersistStreamInit).Load(TStreamAdapter.Create(aStream));
    finally
       aStream.Free;
    end;
    HTMLWindow2 := (WebBrowser1.Document as IHTMLDocument2).parentWindow;
  end;
end;

procedure TViewMaps.GoToAddressBtnClick(Sender: TObject);
begin
   address := MemoAddress.Lines.Text;
   address := StringReplace(StringReplace(Trim(address), #13, ' ', [rfReplaceAll]), #10, ' ', [rfReplaceAll]);
   HTMLWindow2.execScript(Format('codeAddress(%s)',[QuotedStr(address)]), 'JavaScript');
end;

Answer 1

如果要將地址傳遞給映射表單，則可以將其作為表單構造函數的參數傳遞。

創建一個名為fAddress的私有表單變量。

然后添加表單的公共構造函數重寫並傳遞地址：

  Public
    constructor create(AOwner: TComponent; AAddress: string); reintroduce;

implementation

constructor TForm1.create(AOwner: TComponent; AAddress: string);
begin
  inherited create(AOwner);
  fAddress := AAddress; // fAddress is now stored to form variable
end;

您的應用還需要確保首先加載Google API。 您無需使用TTimer，只需驗證TWebBrowser的READY_STATE即可確保Google API已完全加載。 在這里，我已將您的代碼移至表單的OnShow事件（已測試）。

procedure TForm1.FormShow(Sender: TObject);
var
  aStream: TMemoryStream;
begin
  WebBrowser1.Navigate('about:blank');

  if Assigned(WebBrowser1.Document) then
  begin
    aStream := TMemoryStream.Create;
    try
      aStream.WriteBuffer(Pointer(HTMLStr)^, Length(HTMLStr));
      aStream.Seek(0, soFromBeginning);
      (WebBrowser1.Document as IPersistStreamInit).Load(TStreamAdapter.Create(aStream));
    finally
      aStream.Free;
    end;
    HTMLWindow2 := (WebBrowser1.Document as IHTMLDocument2).parentWindow;
  end;

  while WebBrowser1.ReadyState <> READYSTATE_COMPLETE do // wait for google
  begin
    sleep(0);
    application.processmessages;
  end;

  fAddress := StringReplace(StringReplace(Trim(fAddress), #13, ' ', [rfReplaceAll]), #10, ' ', [rfReplaceAll]);
  HTMLWindow2.execScript(Format('codeAddress(%s)',[QuotedStr(fAddress)]), 'JavaScript');
end;

要使用映射表實現和顯示地址，請使用調用表中的以下內容：

Form1 := TForm1.create(self, '15010 NE 36th St, Redmond, WA 98052');
try
  Form1.showmodal;
finally
  Form1.destroy;
end;

在TWebBrowser（Google地圖）中顯示位置，而無需單擊按鈕

問題描述

1 個解決方案

解決方案1
1 已采納 2016-05-10 21:31:51

在TWebBrowser（Google地圖）中顯示位置，而無需單擊按鈕

問題描述

1 個解決方案

解決方案1 1 已采納 2016-05-10 21:31:51

解決方案1
1 已采納 2016-05-10 21:31:51