解决Delphi开发DLL中窗体按钮显示状态不刷新问题.

由于DLL中没有消息循环,在DLL的窗体上放一个TSpeedButton控件, Flat属性设置为True. 运行. 当鼠标从TSpeedButton上移过时, TSpeedButton怎么也还原不了,

需要手动接收消息处理,具体操作如下：

1.在窗体上放置一个Timer1组件,

2.间隔时间为1

3.在Timer1Timer事件中写上一行代码：Application.HandleMessage;

 

附上我的窗体完整代码：

unit untBaseForm;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, Buttons, sSpeedButton, ImgList, StdCtrls, ExtCtrls, IniFiles,
sLabel, untDefine, sSkinManager;

type
TNowDataUser = record
UserName:String; {用户名称}
UserCode:String; {用户帐号}
UserPass:string; {用户密码}
UserFlag:Integer;{用户类型}
end;

{当前数据}
TNowData = record
User: TNowDataUser; {当前用户}
{...}
end;
TBaseForm = class(TForm)
pnlBody: TPanel;
pnlTitle: TPanel;
btnwsClose: TsSpeedButton;
btnwsMin: TsSpeedButton;
btnwsMax: TsSpeedButton;
btnwsNormal: TsSpeedButton;
btnSkin: TsSpeedButton;
btnMenu: TsSpeedButton;
lblTitle: TsLabel;
sm: TsSkinManager;
procedure btnwsCloseClick(Sender: TObject);
procedure btnwsMaxClick(Sender: TObject);
procedure btnwsMinClick(Sender: TObject);
procedure pnlTitleMouseMove(Sender: TObject; Shift: TShiftState; X, Y: Integer);
procedure FormShow(Sender: TObject);
procedure btnSkinClick(Sender: TObject);
procedure FormActivate(Sender: TObject);
procedure FormCreate(Sender: TObject);
private
{ Private declarations }
FDefaultMaxWindows: boolean;
FShowInTaskbar: Boolean;
FShowDll: TTimer; {用于解决Dll中窗体没有消息循环造成按钮上移动不刷新问题}
procedure FShowDllTimer(Sender: TObject);
procedure CreateParams(var Params: TCreateParams); override;
protected
procedure ini_SkinRead; virtual;
procedure ini_SkinWrite(i: Integer); virtual;
procedure SetwsMaxorNormal; virtual;
public
{ Public declarations }
NowData:TNowData; {当前数据,包括当前登录用户信息等..}
/// <summary>
/// 构造函数扩展任务栏是否显示
/// </summary>
/// <param name="AOwner"></param>
/// <param name="ShowTaskbar">True:在任务栏显示(仅在Exe中起作用)</param>
/// <param name="DefaultMaxWindows">默认打开窗口是否最大化(注：如果调整了继承窗体的大小后,更改属性WindowState会失效,所以增加了此参数)</param>
constructor CreateSTB(AOwner: TComponent; ShowTaskbar: Boolean = False;DefaultMaxWindows:Boolean=False); virtual;
published

end;

var
BaseForm: TBaseForm;

implementation

{$R *.dfm}

{关闭}
procedure TBaseForm.btnwsCloseClick(Sender: TObject);
begin
Close;
end;

{最大化}
procedure TBaseForm.btnwsMaxClick(Sender: TObject);
begin
if (btnwsNormal.Visible = false) and (btnwsMax.Visible = False) then exit;
if WindowState = wsNormal then
begin
WindowState := wsMaximized;
SetwsMaxorNormal;
end
else
begin
WindowState := wsNormal;
Self.Left := (Screen.Width div 2) - (Self.Width div 2);
Self.Top := (Screen.Height div 2) - (Self.Height div 2);
SetwsMaxorNormal;
end;
end;

{最小化}
procedure TBaseForm.btnwsMinClick(Sender: TObject);
begin
//Application.Minimize;
WindowState := wsMinimized;
end;

{拖动标题,移动窗体}
procedure TBaseForm.pnlTitleMouseMove(Sender: TObject;
Shift: TShiftState; X, Y: Integer);
begin
if WindowState = wsMaximized then exit;
if ssleft in Shift then ReleaseCapture;
Perform(WM_SYSCOMMAND, $F012, 0);
end;

{点击标题变色}
procedure TBaseForm.btnSkinClick(Sender: TObject);
begin
ini_SkinWrite(pnlTitle.Tag + 1);
ini_SkinRead;
end;

procedure TBaseForm.FormShow(Sender: TObject);
begin
SetwsMaxorNormal;
ini_SkinRead;
Caption := lblTitle.Caption;

{解决Dll中窗体没有消息循环造成按钮上移动不刷新问题}
if  Application.MainForm=nil  then
begin
if not (fsModal in Self.FormState) then
begin
if FShowDll=nil then
begin
FShowDll:= TTimer.Create(Self);
FShowDll.Enabled:=False;
FShowDll.Interval:=1;
FShowDll.OnTimer:= FShowDllTimer;
end;
if not FShowDll.Enabled then FShowDll.Enabled:=true;
end;
end;
end;

{设置最大化一般化按钮状态}
procedure TBaseForm.SetwsMaxorNormal;
begin
if (btnwsNormal.Visible = false) and (btnwsMax.Visible = False) then exit;
btnwsMax.Visible := WindowState = wsNormal;
btnwsNormal.Visible := WindowState = wsMaximized;
btnwsNormal.Left := btnwsMax.Left;
btnwsNormal.Top := btnwsMax.Top;
end;

{加载皮肤颜色}
procedure TBaseForm.ini_SkinRead;
var
ini: TIniFile;
i: integer;
begin
ini := TIniFile.Create(ExtractFilePath(ParamStr(0)) + 'skin.dat');
try
pnlTitle.Tag := ini.ReadInteger('skin', 'color', 0);
if pnlTitle.Tag > High(G_FormSkinColor) then pnlTitle.Tag := 0;
finally
FreeAndNil(ini);
end;
pnlTitle.Color := G_FormSkinColor[pnlTitle.Tag];
pnlTitle.Refresh;

for i := 0 to pnlTitle.ControlCount - 1 do
begin
if pnlTitle.Controls[i].Visible then
begin
pnlTitle.Controls[i].Hide;
pnlTitle.Controls[i].Show;
end;
end;
end;

{保存皮肤颜色}
procedure TBaseForm.ini_SkinWrite(i: Integer);
var
ini: TIniFile;
begin
if i > High(G_FormSkinColor) then i := 0;
ini := TIniFile.Create(ExtractFilePath(ParamStr(0)) + 'skin.dat');
try
ini.WriteInteger('skin', 'color', i);
finally
FreeAndNil(ini);
end;
end;

procedure TBaseForm.CreateParams(var Params: TCreateParams);
begin
inherited;
if FShowInTaskbar then Params.WndParent := 0; //在任务栏显示标题
end;

constructor TBaseForm.CreateSTB(AOwner: TComponent; ShowTaskbar: Boolean = False;DefaultMaxWindows:Boolean=False);
begin
if (ShowTaskbar)  and (Application.MainForm<>nil) then FShowInTaskbar := True;
FDefaultMaxWindows:=DefaultMaxWindows;
inherited Create(AOwner);
//if not ShowTaskbar then SetWindowLong(Self.Handle, GWL_EXSTYLE, WS_EX_TOOLWINDOW);
end;

procedure TBaseForm.FormCreate(Sender: TObject);
begin
if (WindowState = wsMaximized) or (FDefaultMaxWindows=True) then
begin
FDefaultMaxWindows := true;
WindowState := wsNormal;
Position := poDefault;
end;
end;

procedure TBaseForm.FormActivate(Sender: TObject);
begin
if FDefaultMaxWindows then
begin
WindowState := wsMaximized;
FDefaultMaxWindows := false;
end;
end;

procedure TBaseForm.FShowDllTimer(Sender: TObject);
begin
if (Self<>nil ) and (Self.Visible) then
Application.HandleMessage;
end;

end.

 DLL工程文件：

library Sale;

uses
SysUtils,
Classes,
Forms,
Controls,
Windows,
untBaseDM in '..\Common\untBaseDM.pas' {BaseDM: TDataModule},
untBaseForm in '..\Common\untBaseForm.pas' {BaseForm},
untSaleDemo in 'untSaleDemo.pas' {fmSaleDemo},
untDM in 'untDM.pas' {DM: TDataModule};

{$R *.res}

/// <summary>
/// 获取fmSaleDemo
/// </summary>
/// <param name="Taskbar">是否在任务栏显示(True时不建议ShowModal窗体)</param>
/// <param name="New">是否重新创建</param>
/// <param name="MaxWindows">是否最大化窗体</param>
/// <param name="NowData">当前数据</param>
/// <param name="AHandle">Application.Handle</param>
/// <returns>fmSaleDemo</returns>
function GetFormSaleDemo(Taskbar: Boolean; New: Boolean; MaxWindows:Boolean; NowData:TNowData; AHandle: Thandle=0): TBaseForm; stdcall;
begin
if Taskbar=False then Application.Handle:= AHandle;
if (New) and (fmSaleDemo <> nil) then FreeAndNil(fmSaleDemo);
if fmSaleDemo = nil then fmSaleDemo := TfmSaleDemo.CreateSTB(nil, Taskbar, MaxWindows);
fmSaleDemo.NowData:=NowData;
Result := fmSaleDemo;
end;

exports
GetFormSaleDemo;

begin
end.

 

 

主程序调用：

 

function GetFormSaleDemo(Taskbar: Boolean; New: Boolean; MaxWindows: Boolean; NowData: TNowData; AHandle: Thandle = 0): TBaseForm; stdcall; external 'Sale.dll';

procedure TfmMain.btnSaleOrderClick(Sender: TObject);
var
frm:TBaseForm;
begin
frm := GetFormSaleDemo(False, True, False, NowData, Application.Handle);
frm.ShowModal
end;