小编Ulr*_*nin的帖子

我阅读了Kivy教程,但无法找到如何禁用窗口小部件(例如,按钮).

def foo(self, instance, *args):
  #... main business logic, and then
  instance.disable = False
  # type(instance) = kivy.uix.Button

我结合foo使用functools.partial.

什么是正确的参数？

我想用Delphi实现观察者模式.这是一个接口ISubject和一个TWeatherData实现观察者的类.

ISubject = interface
    procedure notifyObservers;
    procedure removeObserver(o: IObserver);
    procedure registerObserver(o: IObserver);
  end;

TWeatherData = class(TInterfacedObject, ISubject)
  private
    observers: TList;
    FTemperature: Double;
    FHumidity: Double;
    FPressure: Double;
  public
    // ...
    procedure notifyObservers;
    procedure setMeasurements(ATemperature, AHumidity, APressure: Double);
  end;

我得到一个访问冲突有关的读取地址的时候TWeatherData.notifyObservers执行

procedure TWeatherData.notifyObservers;
var
  observer: ^IObserver;
begin
  for observer in observers do
    observer.Update(FTemperature, FHumidity, FPressure); //oops -> there raised AV.
end;


procedure TWeatherData.setMeasurements(ATemperature, AHumidity,
  APressure: Double);
begin
  measurementsChanged; // and this one calls …

再会，

我第一次出现这种错误。

// another.h
struct Item {
  QString name = QString();
  QString description = QString();
  QVariant value = QVariant();
  struct Interface {
    uint id = 0;
    uint pos = 0;
  } mkio, uks;
  struct Element {
    float weight = 0;
    struct Range {
      uint from = 0;
      uint to = 0;
    } range;
  int index = 0;
} element;
};

我想将此嵌套结构存储在流中。所以，

// another.h
QDataStream &operator<<(QDataStream &out, const Item::Interface &interface)
{
  return out << interface.id
             << interface.pos;
}
// and another …

美好的一天,

我有课

TMn2Adapter = class(TPersistent)  
  private
    FGrid: TStringGridPointer;
    FList: TList<string>;
    // ...

  public

  constructor Create(AGrid: TStringGridPointer);
  destructor Destroy();
end;

constructor TMn2Adapter.Create(AGrid: TStringGridPointer);
begin
  FGrid := AGrid;
  FList := TList<string>.Create();
end;

destructor TMn2Adapter.Destroy;
begin
  Dispose(FGrid);

  FList.Free;
  FList := nil;

  inherited;
end;

还有一个

TMn2Worker = class(TPersistent)
  private
    FMn2Adapter: TMn2Adapter;
  public
    constructor Create(AGrid: TStringGridPointer);
    destructor Destroy();
end;

constructor TMn2Worker.Create(AGrid: TStringGridPointer);
begin
  FMn2Adapter := TMn2Adapter.Create(AGrid);
end;


destructor TMn2Worker.Destroy;
begin

  SysUtils.FreeAndNil(FMn2Adapter);

  inherited;
end;

procedure TMn2Adapter.Parse;
begin
  FList.Clear();
  for I := 1 to FLenght do FList.Add((FGrid)^.Cells[2, …