Delphi中的Java内部类

debugcn 发表于 Dev

用户名

我是Delphi的新手，我有一些用Java编写的代码。它具有内部类结构。但是我不知道如何转换为Delphi。

unit resolutionSet;

interface

uses
  Winapi.Windows, System.Math;

type
TResolutionSet = class
  type
  TResolutionLevel = class
  private
    { private declarations }
    discardLayers : Integer;
    dims          : TRect;
    function getZoomLevel : Integer;
    function getZoomPercent : Double;
    function getResolutionBounds : TRect;
    constructor Create(_discardLayers : Integer; _dims : TRect) overload;
  protected
    { protected declarations }
  public
    { public declarations }
  published
    { published declarations }
  end;
private
  { private declarations }
  resolutions : array of TResolutionLevel;
protected
  { protected declarations }
public
  { public declarations }
  function getResolutionLevel(_currRes : TResolutionLevel; _delta : Integer) : TResolutionLevel overload;
  function getResolutionLevel(_index : Integer) : TResolutionLevel overload;
  function getClosestResolutionLevel(_source : Double; _target : Double) : TResolutionLevel;
  procedure addResolutionLevel(_discardLayer : Integer; _dims : TRect);
  constructor Create(_numResolutions : Integer) overload;
published
  { published declarations }
end;
implementation

constructor TResolutionSet.Create(_numResolutions : Integer) overload;
begin
  SetLength(resolutions, _numResolutions);
end;

procedure TResolutionSet.addResolutionLevel(_discardLayer : Integer; _dims : TRect);
begin
  resolutions[_discardLayer]:= TResolutionLevel.Create(_discardLayer, _dims);
end;

function TResolutionSet.getResolutionLevel(_currRes : TResolutionLevel; _delta : Integer) : TResolutionLevel overload;
begin
  //Result:= resolutions
end;

function TResolutionSet.getResolutionLevel(_index : Integer) : TResolutionLevel overload;
begin
  Result:= resolutions[_index];
end;

function TResolutionSet.getClosestResolutionLevel(_source : Double; _target : Double) : TResolutionLevel;
var
  idx : Integer = 0;
  i   : Integer;
begin
  for i := Length(resolutions)-1 downto 0 do
  begin
    idx:= i;
    if (_source * Power(2, resolutions[i].getZoomLevel())) <= _target then
      break;
  end;
  Result:= resolutions[idx];
end;

end.

我为内部类声明了TResolutionLevel，但是如何在哪里实现此类的方法呢？

达莉娅（Dalija Prasnikar）

如果您在类接口声明中时按Shift+ Ctrl+ C，则Delphi将自动生成缺少的方法。在您的情况下，这些是：

{ TResolutionSet.TResolutionLevel }

constructor TResolutionSet.TResolutionLevel.Create(_discardLayers: Integer; _dims: TRect);
begin

end;

function TResolutionSet.TResolutionLevel.getResolutionBounds: TRect;
begin

end;

function TResolutionSet.TResolutionLevel.getZoomLevel: Integer;
begin

end;

function TResolutionSet.TResolutionLevel.getZoomPercent: Double;
begin

end;

如您所见，通过提供每个方法的完全限定名称，您可以像实现任何其他类的方法一样实现内部类的方法。对于嵌套类，这意味着包括外部类的名称。

本文收集自互联网，转载请注明来源。

如有侵权，请联系[email protected] 删除。