Importing dwmapi.dll

[Ian Martinez]

On Sunday, 16 September 2012 at 02:22:42 UTC, jerro wrote:
> On Sunday, 16 September 2012 at 00:27:19 UTC, Ian Martinez 
> wrote:
>> I'm new to D(really new, just learned it today) and I'm making 
>> a little program that I want to extend the aero glass into 
>> I've written this:
>> struct MARGINS {
>>  int cxLeftWidth;
>>  int cxRightWidth;
>>  int cyTopHeight;
>>  int cyBottomHeight;
>> }
>> HRESULT extendaeroglass(HWND handle,int left,int right,int 
>> top,int bottom){
>> 	MARGINS aeromargins = {left,right,top,bottom};
>> 	HRESULT hr = IDOK;
>> 	hr = DwmExtendFrameIntoClientArea(handle,aeromargins);
>
> This line should be
>
> hr = DwmExtendFrameIntoClientArea(handle,&aeromargins);
>
>> 	return hr;
>> }
>> But I can't seem to figure out how to import dwmapi, I googled 
>> and there was something that said I'd have to translate the 
>> header file(dwmapi.h) which is 532 lines long, which I can't 
>> do that well because I'm not that good at D and my C/C++ is 
>> even worse and another page said I need to include the .lib 
>> file(converted from COFF) in it, which I did and it still 
>> won't work:
>> Error:undefined identifier DwmExtendFrameIntoClientArea
>
> The functions need to be declared if you want to use them. For 
> c libraries you usually import modules that contain the 
> declarations, but when there isn't one already written, you 
> need to declare them yourself. You don't need to translate all 
> of dwmapi.h, just the parts that you use. For 
> DvmExtendFrameIntoClientArea you would do this:
>
> extern(Windows)
>     HRESULT DwmExtendFrameIntoClientArea(HWND, MARGINS*);
>
> This tells the compiler that there is a functions with this 
> name, parameter types, return type and using Windows name 
> mangling and calling convention. The implementation of this 
> function needs to be available when linking, which is why the 
> .lib file is also needed.

Thank you so much!!