You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: main.go
    path of file: ./repos/govcl/samples/dropfiles
    
    the code of the file until where you have to start completion: package main

import (
	"fmt"

	"github.com/ying32/govcl/vcl"

	_ "github.com/ying32/govcl/pkgs/winappres"
)

type TMainForm struct {
	*vcl.TForm
}

var mainForm *
    
func (f *TMainForm) OnFormCreate(object vcl.IObject) {
	f.SetCaption("drop files")
	f.SetWidth(300)
	f.SetHeight(200)
	f.ScreenCenter()
	f.EnabledMaximize(false)

	// allow drop file
	f.SetAllowDropFiles(true)

	// windows10没生效，有待研究
	windowsUACMessageFilter(f.Handle())
}