如何访问嵌套样式控件

时间:2018-09-24 11:46:39

标签: delphi firemonkey delphi-10.2-tokyo firemonkey-style

我有自定义样式的FireMonkey控件。其样式包含多层嵌套控件。

我需要访问这些控件并在运行时更改某些样式属性。为此,我正在使用FindStyleResource<T>方法。

检索样式中的第一级控件没有问题。但是,如果控件父级是FindStyleResource的后代,则使用TStyledControl访问第二级控件将失败。

问题是如何访问这些嵌套样式控件而不管其父类型如何?

样式:

object TStyleContainer
  object TLayout
    StyleName = 'MyHeader'
    Align = Center
    Size.Width = 100.000000000000000000
    Size.Height = 50.000000000000000000
    Size.PlatformDefault = False
    Visible = False
    TabOrder = 0
    object TLabel
      StyleName = 'title'
      Align = Client
      StyledSettings = [Style]
      Size.Width = 36.000000000000000000
      Size.Height = 50.000000000000000000
      Size.PlatformDefault = False
      TextSettings.HorzAlign = Center
      Text = 'Title'
    end
    object TLayout
      StyleName = 'green'
      Align = MostLeft
      Size.Width = 32.000000000000000000
      Size.Height = 50.000000000000000000
      Size.PlatformDefault = False
      object TPath
        StyleName = 'greenpath'
        Align = Fit
        Data.Path = {
          07000000000000000000404100000041010000000000C0400000604101000000
          B81EED405C8F76410100000000004041AE472D410100000052B884415C8F7641
          010000000000904100006041030000000000404100000041}
        Fill.Color = claGreen
        HitTest = False
        Size.Width = 32.000000000000000000
        Size.Height = 50.000000000000000000
        Size.PlatformDefault = False
        Stroke.Kind = None
        WrapMode = Fit
      end
    end
    object TSpeedButton
      StyleName = 'red'
      Align = MostRight
      Position.X = 68.000000000000000000
      Size.Width = 32.000000000000000000
      Size.Height = 50.000000000000000000
      Size.PlatformDefault = False
      object TPath
        StyleName = 'redpath'
        Align = Fit
        Data.Path = {
          07000000000000000000404100000041010000000000C0400000604101000000
          B81EED405C8F76410100000000004041AE472D410100000052B884415C8F7641
          010000000000904100006041030000000000404100000041}
        Fill.Color = claRed
        HitTest = False
        Size.Width = 32.000000000000000000
        Size.Height = 32.571426391601560000
        Size.PlatformDefault = False
        Stroke.Kind = None
        WrapMode = Fit
      end
    end
  end
end

控件:

type
  TMyHeader = class(TStyledControl)
  protected
    procedure ApplyStyle; override;
    function GetDefaultStyleLookupName: string; override;
   end;

procedure TMyHeader.ApplyStyle;
var
  LGreen: TLayout;
  LGreenPath: TPath;
  LRed: TSpeedButton;
  LRedPath: TPath;
begin
  inherited;
  if FindStyleResource<TLayout>('green', LGreen) then
    begin
      // following call will find greenpath control 
      if FindStyleResource<TPath>('greenpath', LGreenPath) then
        LGreenPath.Fill.Color := TAlphaColorRec.Blue;
    end;

  if FindStyleResource<TSpeedButton>('red', LRed) then
    begin 
      // following call will fail to find find redpath control  
      if FindStyleResource<TPath>('redpath', LRedPath) then
        LRedPath.Fill.Color := TAlphaColorRec.Blue;

      // this variant also fails
      if LRed.FindStyleResource<TPath>('redpath', LRedPath) then
        LRedPath.Fill.Color := TAlphaColorRec.Blue;
    end;
end;

function TMyHeader.GetDefaultStyleLookupName: string;
begin
  Result := 'MyHeader';
end;

原始样式:

enter image description here

样式已更改(仅成功更改了绿色箭头颜色)

enter image description here

ApplyStyle方法中,我可以从样式中访问greenpath并将其颜色更改为蓝色。但是,我无法使用redpath方法获得FindStyleResource

1 个答案:

答案 0 :(得分:0)

访问样式元素的标准方法是通过journey_role_user并迭代子样式对象。

尝试一下:

TFMXObject

更新的代码procedure TMyHeader.ApplyStyle; var objFMX, inObjFMX: TFMXObject; LRed: TSpeedButton; LRedPath: TPath; begin inherited; objFMX:=FindStyleResource('red'); if assigned(objFMX) and (objFMX is TSpeedButton) then begin LRed:=objFMX as TSpeedButton; inObjFMX:=LRed.FindStyleResource('redpath'); if assigned(inObjFMX) and (inObjFMX is TPath) then begin LRedPath:=inObjFMX as TPath; LRedPath.Fill.Color := TAlphaColorRec.Blue; end; end end; 在以上代码中无效。下面是另一种方法。

FindStyleResource

适用于10.2