Redraw a control periodically using a timer

IPlugEffect.cpp

#include "IPlugEffect.h"
#include "IPlug_include_in_plug_src.h"
#include "IControls.h"

class MyControl : public IControl {
public:
  MyControl(const IRECT& r)
  : IControl(r)
  {
    mTimer = std::unique_ptr<Timer>(Timer::Create([&](Timer& t) {
      mColor = IColor::GetRandomColor();
      this->SetDirty(false);
    }, 100));
  }
  
  void Draw(IGraphics &g) override
  {
    g.FillEllipse(mColor, mRECT);
  }
  
private:
  IColor mColor = COLOR_BLUE;
  std::unique_ptr<Timer> mTimer;
};


IPlugEffect::IPlugEffect(const InstanceInfo& info)
: Plugin(info, MakeConfig(kNumParams, kNumPresets))
{
  GetParam(kGain)->InitDouble("Gain", 0., 0., 100.0, 0.01, "%");

#if IPLUG_EDITOR // http://bit.ly/2S64BDd
  mMakeGraphicsFunc = [&]() {
    return MakeGraphics(*this, PLUG_WIDTH, PLUG_HEIGHT, PLUG_FPS, GetScaleForScreen(PLUG_WIDTH, PLUG_HEIGHT));
  };
  
  mLayoutFunc = [&](IGraphics* pGraphics) {
    pGraphics->AttachCornerResizer(EUIResizerMode::Scale, false);
    pGraphics->AttachPanelBackground(COLOR_GRAY);
    pGraphics->LoadFont("Roboto-Regular", ROBOTO_FN);
    const IRECT b = pGraphics->GetBounds();
    pGraphics->AttachControl(new MyControl(b.GetCentredInside(100)));
  };
#endif
}

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