iosWebViewFix/flutter_inappwebview_windows/windows/utils/util.h

38 lines
1.0 KiB
C++

#ifndef FLUTTER_INAPPWEBVIEW_PLUGIN_UTIL_H_
#define FLUTTER_INAPPWEBVIEW_PLUGIN_UTIL_H_
#include <optional>
#include <string>
#include <variant>
#include <Windows.h>
namespace flutter_inappwebview_plugin
{
template<typename T>
static inline std::optional<T> make_pointer_optional(const T* value)
{
return value == nullptr ? std::nullopt : std::make_optional<T>(*value);
}
static inline std::string variant_to_string(const std::variant<std::string, int64_t>& var)
{
return std::visit([](auto&& arg)
{
using T = std::decay_t<decltype(arg)>;
if constexpr (std::is_same_v<T, std::string>)
return arg;
else if constexpr (std::is_arithmetic_v<T>)
return std::to_string(arg);
else
static_assert(always_false_v<T>, "non-exhaustive visitor!");
}, var);
}
static inline float get_current_scale_factor(HWND hwnd)
{
auto dpi = GetDpiForWindow(hwnd);
return dpi > 0 ? dpi / 96.0f : 1.0f;
}
}
#endif //FLUTTER_INAPPWEBVIEW_PLUGIN_UTIL_H_