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Re: Issues using 2015.2 version [message #45894 is a reply to message #45893]

Thu, 21 January 2016 18:34

Lance
Messages: 527
Registered: March 2007

Contributor

Hi Giorgio：

Not sure if you are directly using the BarcodeTest program, anyway, the following line generates the problem you referred to

GUI_APP_MAIN
{
	auto a=MyApp();                       <============ This line
	a.Sizeable().MaximizeBox();
	a.Maximize();
	a.Run();

}

while MyApp has this definition

struct MyApp : WithBarcodeTestLayout<TopWindow>
{
	MyApp(){
		CtrlLayout(*this, "Barcode Test");
		input<<=THISBACK(Updated);
		print.SetImage(CtrlImg::print())<<=THISBACK(Print);
		top<<=2;
		left<<=2;
	}
	
	virtual void Paint(Draw& w);
	
	void GenBarcode();
	void Print();
	
	void Updated()
	{
		Refresh();
		Code128 c(String().Cat()<<~input);
		EAN ean(AsString(~input));
		PDF417 pdf(AsString(~input));
		richview.SetQTF(String("[ ").Cat()
			<<c.DisplayText("Hi, U++ user!")
				.Color(Red()).BarRatio(36)
			<<"&&" // new line
			<<ean.Type(EAN::EAN8UPCAEAN13)
				.DisplayText("Best Seller")
			<<"&&"
			<<pdf.FixedAspectRatio(3,2)
		);
	}
	
	typedef MyApp CLASSNAME;
	
};

There are not even any data members (except ones inherits from its ancestors) in the MyApp struct definition, so it could not be because of anything from my barcode library.

I am also puzzled on that line. Logically local variable a should be default constructed once, instead of a default construct of a temporary and then an assignment, so it should be equivalent to

    MyApp a;

Apparently I was wrong. Anyway, change the line to above fixed the problem. I was wondering why should I use the more cumbersome form at first place. So if you are using the BarcodeTest program directly, change the GUI_MAIN to the following form will fix your problem:

GUI_APP_MAIN
{
	MyApp a;
	a.Sizeable().MaximizeBox();
	a.Maximize();
	a.Run();

}

HTH

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