audacity/src/widgets/Grabber.cpp

/**********************************************************************

  Audacity: A Digital Audio Editor

  Grabber.cpp

  Leland Lucius

*******************************************************************//**

\file Grabber.cpp

  Implements Grabber

*//*******************************************************************//**

\class Grabber
\brief The widget to the left of a ToolBar that allows it to be dragged
around to NEW positions.

*//**********************************************************************/

#include "../Audacity.h"
#include "Grabber.h"

#include <wx/defs.h>
#include <wx/dcclient.h>
#include <wx/event.h>
#include <wx/intl.h>
#include <wx/window.h>

#include "../AColor.h"
#include "../AllThemeResources.h"
#include "../Internat.h"

////////////////////////////////////////////////////////////
/// Methods for Grabber
////////////////////////////////////////////////////////////

DEFINE_EVENT_TYPE(EVT_GRABBER_CLICKED)

BEGIN_EVENT_TABLE(Grabber, wxWindow)
   EVT_ENTER_WINDOW(Grabber::OnEnter)
   EVT_LEAVE_WINDOW(Grabber::OnLeave)
   EVT_LEFT_DOWN(Grabber::OnLeftDown)
   EVT_ERASE_BACKGROUND( Grabber::OnErase )
   EVT_PAINT(Grabber::OnPaint)
   EVT_KEY_DOWN(Grabber::OnKeyDown)
END_EVENT_TABLE()

//
// Constructor
//
Grabber::Grabber(wxWindow * parent, wxWindowID id)
: wxWindow(parent,
           id,
           wxDefaultPosition,
           wxSize(grabberWidth, 27),
           wxFULL_REPAINT_ON_RESIZE)
{
   mOver = false;
   mPressed = false;
   mAsSpacer = false;
   SetBackgroundColour( theTheme.Colour( clrMedium ) );

   /* i18n-hint: A 'Grabber' is a region you can click and drag on
   It's used to drag a track around (when in multi-tool mode) rather
   than requiring that you use the drag tool.  It's shown as a series
   of horizontal bumps */

   SetLabel(_("Grabber"));
   SetName(_("Grabber"));
}

//
// Destructor
//
Grabber::~Grabber()
{
}

//
// Queue a drag event
//
void Grabber::SendEvent(wxEventType type, const wxPoint & pos, bool escaping)
{
   wxWindow *parent = GetParent();

   // Initialize event and convert mouse coordinates to screen space
   GrabberEvent e(type, GetId(), parent->ClientToScreen(pos), escaping);

   // Set the object of our desire
   e.SetEventObject(parent);

   // Queue the event
   parent->GetEventHandler()->AddPendingEvent(e);
}

void Grabber::SetAsSpacer( bool bIsSpacer ) { 
   if( mAsSpacer != bIsSpacer ){
      // HACK: Use a wider rectangle to also cover one pixel of space just to the right.
      wxSize siz = GetSize();
      siz.IncBy( bIsSpacer ? 1:-1, 0 );
      SetSize( siz );
   }
   mAsSpacer = bIsSpacer;
};

void Grabber::SetToolTip(TranslatableString toolTip)
{
   wxWindow::SetToolTip( toolTip.Strip().Translation() );
}

//
// Draw the grabber
//
void Grabber::DrawGrabber( wxDC & dc )
{
   wxRect r = GetRect();
   // PaintDC positions are relative to the grabber, not the parent window.
   // So use 0,0 as origin for draw, so that the grabber draws right if 
   // positioned in its parent at some non zero position.
   r.SetPosition( wxPoint(0,0) );
   int y, left, right, top, bottom;

   AColor::Medium(&dc, mOver );
   dc.DrawRectangle(r);

   // HACK: We used a wider rectangle to also cover one pixel of space just to the right.
   if( mAsSpacer )
      r.width -= 1;

#ifndef __WXMAC__

   // Add a box
   r.width -= 1;
   r.height -= 1;
   AColor::Bevel(dc, !mPressed, r);
   r.width += 1;
   r.height += 1;

#endif

   // No bumps in a spacer grabber.
   if( mAsSpacer )
      return;
   // Calculate the bump rectangle
   r.Deflate(3, 3);
   if ((r.GetHeight() % 4) < 2) {
      r.Offset(0, 1);
   }

   // Cache
   left = r.GetLeft();
   right = r.GetRight();
   top = r.GetTop();
   bottom = r.GetBottom();

   // Draw the raised bumps
   if (mPressed) {
      AColor::Dark(&dc, false);
   }
   else {
      AColor::Light(&dc, false);
   }

   for (y = top; y < bottom; y += 4) {
      AColor::Line(dc, left, y, right, y);
   }

   // Draw the pushed bumps
   if (mPressed) {
      AColor::Light(&dc, false);
   }
   else {
      AColor::Dark(&dc, false);
   }

   for (y = top + 1; y <= bottom; y += 4) {
      AColor::Line(dc, left, y, right, y);
   }
}

//
// Change the button state
//
void Grabber::PushButton(bool state )
{
   if( mAsSpacer )
      return;
   wxRect r = GetRect();
   mOver = r.Contains(ScreenToClient(wxGetMousePosition()));

   // Redraw button
   mPressed = state;
   Refresh(false);
}

//
// Handle left button down events
//
void Grabber::OnLeftDown(wxMouseEvent & event)
{
   // Button should be drawn pushed
   PushButton(true);

   // Notify parent
   SendEvent(EVT_GRABBER_CLICKED, event.GetPosition(), false);

   event.Skip();
}

//
// Handle mouse enter events
//
void Grabber::OnEnter(wxMouseEvent & WXUNUSED(event))
{
   // Bug 1201:  On Mac, unsetting and re-setting the tooltip may be needed
   // to make it pop up when we want it.
   const auto text = GetToolTipText();
   UnsetToolTip();
   wxWindow::SetToolTip(text);

   if( mAsSpacer )
      return;

   // Redraw highlighted
   mOver = true;
   Refresh(false);
}

//
// Handle mouse leave events
//
void Grabber::OnLeave(wxMouseEvent & WXUNUSED(event))
{
   if (!GetCapture()) {
      // Redraw plain
      mOver = false;
      Refresh(false);
   }
}

void Grabber::OnErase( wxEraseEvent & WXUNUSED(event) )
{
   // Ignore it to prevent flashing
}

//
// Handle the paint events
//
void Grabber::OnPaint(wxPaintEvent & WXUNUSED(event))
{
   wxPaintDC dc(this);

   // Redraw the grabber
   DrawGrabber(dc);
}

void Grabber::OnKeyDown(wxKeyEvent &event)
{
   event.Skip();

   if(event.GetKeyCode() == WXK_ESCAPE) {
      // We must not only skip this key event, but propagate it up the window
      // hierarchy, so that ToolFrame detects it too.
      event.ResumePropagation(wxEVENT_PROPAGATE_MAX);
      SendEvent(EVT_GRABBER_CLICKED, wxPoint{ -1, -1 }, true);
   }
}

// Piggy back in same source file as Grabber.
// Audcaity Flicker-free StaticBitmap.
BEGIN_EVENT_TABLE(AStaticBitmap,wxStaticBitmap)
    EVT_ERASE_BACKGROUND(AStaticBitmap::OnErase)
END_EVENT_TABLE()