作者:mobiledu2502898533 | 来源:互联网 | 2023-02-02 17:09
我想画一些东西.因为GUI冻结我想在一个线程中绘制.但有时我想暂停绘图(几分钟).
Delphi的文档说暂停/恢复已经过时,但没有说明哪些功能取代了它们.
不推荐使用Suspend和Resume.Sleep和SpinWait显然是不合适的.令人惊讶的是,德尔福没有提供这样的基本属性/功能.
那么,我如何暂停/恢复一个线程?
1> Peter Kostov..:
您可能需要fPaused/fEvent
通过关键部分进行保护.这取决于您的具体实施.
interface
uses
Classes, SyncObjs;
type
TMyThread = class(TThread)
private
fEvent: TEvent;
fPaused: Boolean;
procedure SetPaused(const Value: Boolean);
protected
procedure Execute; override;
public
constructor Create(const aPaused: Boolean = false);
destructor Destroy; override;
property Paused: Boolean read fPaused write SetPaused;
end;
implementation
constructor TMyThread.Create(const aPaused: Boolean = false);
begin
fPaused := aPaused;
fEvent := TEvent.Create(nil, true, not fPaused, '');
inherited Create(false);
end;
destructor TMyThread.Destroy;
begin
Terminate;
fEvent.SetEvent;
WaitFor;
fEvent.Free;
inherited;
end;
procedure TMyThread.Execute;
begin
while not Terminated do
begin
fEvent.WaitFor(INFINITE);
// todo: your drawings here
end;
end;
procedure TMyThread.SetPaused(const Value: Boolean);
begin
if (not Terminated) and (fPaused <> Value) then
begin
fPaused := Value;
if fPaused then
fEvent.ResetEvent else
fEvent.SetEvent;
end;
end;