Aegisub/aegisub/src/placeholder_ctrl.h

120 lines
4.2 KiB
C++

// Copyright (c) 2012, Thomas Goyne <plorkyeran@aegisub.org>
//
// Permission to use, copy, modify, and distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
//
// Aegisub Project http://www.aegisub.org/
/// @file placeholder_ctrl.h
/// @ingroup custom_control
///
#ifndef AGI_PRE
#include <wx/settings.h>
#endif
/// @class Placeholder
/// @brief A wrapper around a control to add placeholder text
///
/// This control wraps a base control to add default greyed-out placeholder
/// text describing the control when the value would otherwise be empty, which
/// is removed when the control is focused to begin typing in it, and restored
/// when the control loses focus and the value is empty
template<class BaseCtrl>
class Placeholder : public BaseCtrl {
wxString placeholder; ///< Placeholder string
bool is_placeholder; ///< Should the value be cleared on focus?
/// Wrapper around Create to make it possible to override it for specific
/// base classes
inline void Create(wxWindow *parent, wxSize const& size, long style) {
BaseCtrl::Create(parent, -1, placeholder, wxDefaultPosition, size, style);
}
#ifndef __WXOSX__
/// Focus gained event handler
void OnSetFocus(wxFocusEvent& evt) {
evt.Skip();
if (is_placeholder) {
BaseCtrl::ChangeValue("");
BaseCtrl::SetForegroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_WINDOWTEXT));
}
}
/// Focus lost event handler
void OnKillFocus(wxFocusEvent& evt) {
evt.Skip();
ChangeValue(BaseCtrl::GetValue());
}
public:
/// Constructor
/// @param parent Parent window
/// @param placeholder Placeholder string
/// @param size Control size
/// @param style Style flags to pass to the base control
/// @param tooltip Tooltip string
Placeholder(wxWindow *parent, wxString const& placeholder, wxSize const& size, long style, wxString const& tooltip)
: placeholder(placeholder)
, is_placeholder(true)
{
Create(parent, size, style);
BaseCtrl::SetToolTip(tooltip);
BaseCtrl::SetForegroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_GRAYTEXT));
BaseCtrl::Bind(wxEVT_SET_FOCUS, &Placeholder::OnSetFocus, this);
BaseCtrl::Bind(wxEVT_KILL_FOCUS, &Placeholder::OnKillFocus, this);
}
/// @brief Change the value of the control without triggering events
/// @param new_value New value of the control
///
/// If new_value is empty, the control will switch to placeholder mode
void ChangeValue(wxString new_value) {
if (new_value.empty() && !this->HasFocus()) {
is_placeholder = true;
new_value = placeholder;
BaseCtrl::SetForegroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_GRAYTEXT));
}
else {
is_placeholder = false;
BaseCtrl::SetForegroundColour(wxSystemSettings::GetColour(wxSYS_COLOUR_WINDOWTEXT));
}
// This check should be pointless, but wxGTK is awesome and generates
// change events in wxComboBox::ChangeValue
if (new_value != BaseCtrl::GetValue())
BaseCtrl::ChangeValue(new_value);
}
/// Override GetValue to return empty when in placeholder mode rather than the placeholder text
wxString GetValue() const {
if (is_placeholder && !this->HasFocus())
return "";
return BaseCtrl::GetValue();
}
#else
public:
Placeholder(wxWindow *parent, wxString const& placeholder, wxSize const& size, long style, wxString const& tooltip)
: placeholder(placeholder)
{
Create(parent, size, style);
BaseCtrl::SetToolTip(tooltip);
SetPlaceholderText(this, placeholder);
}
#endif
};
template<> inline void Placeholder<wxComboBox>::Create(wxWindow *parent, wxSize const& size, long style) {
wxComboBox::Create(parent, -1, "", wxDefaultPosition, size, 0, 0, style);
}