juce/source/src/gui/components/layout/juce_ComponentMovementWatcher.cpp

   1 /*
   2   ==============================================================================
   3
   4    This file is part of the JUCE library - "Jules' Utility Class Extensions"
   5    Copyright 2004-11 by Raw Material Software Ltd.
   6
   7   ------------------------------------------------------------------------------
   8
   9    JUCE can be redistributed and/or modified under the terms of the GNU General
  10    Public License (Version 2), as published by the Free Software Foundation.
  11    A copy of the license is included in the JUCE distribution, or can be found
  12    online at www.gnu.org/licenses.
  13
  14    JUCE is distributed in the hope that it will be useful, but WITHOUT ANY
  15    WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  16    A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
  17
  18   ------------------------------------------------------------------------------
  19
  20    To release a closed-source product which uses JUCE, commercial licenses are
  21    available: visit www.rawmaterialsoftware.com/juce for more information.
  22
  23   ==============================================================================
  24 */
  25
  26 #include "../../../core/juce_StandardHeader.h"
  27
  28 BEGIN_JUCE_NAMESPACE
  29
  30 #include "juce_ComponentMovementWatcher.h"
  31 #include "../../../containers/juce_ScopedValueSetter.h"
  32 #include "../windows/juce_ComponentPeer.h"
  33
  34
  35 //==============================================================================
  36 ComponentMovementWatcher::ComponentMovementWatcher (Component* const component_)
  37     : component (component_),
  38       lastPeerID (0),
  39       reentrant (false),
  40       wasShowing (component_->isShowing())
  41 {
  42     jassert (component != nullptr); // can't use this with a null pointer..
  43
  44     component->addComponentListener (this);
  45
  46     registerWithParentComps();
  47 }
  48
  49 ComponentMovementWatcher::~ComponentMovementWatcher()
  50 {
  51     if (component != nullptr)
  52         component->removeComponentListener (this);
  53
  54     unregister();
  55 }
  56
  57 //==============================================================================
  58 void ComponentMovementWatcher::componentParentHierarchyChanged (Component&)
  59 {
  60     if (component != nullptr && ! reentrant)
  61     {
  62         const ScopedValueSetter<bool> setter (reentrant, true);
  63
  64         ComponentPeer* const peer = component->getPeer();
  65         const uint32 peerID = peer != nullptr ? peer->getUniqueID() : 0;
  66
  67         if (peerID != lastPeerID)
  68         {
  69             componentPeerChanged();
  70
  71             if (component == nullptr)
  72                 return;
  73
  74             lastPeerID = peerID;
  75         }
  76
  77         unregister();
  78         registerWithParentComps();
  79
  80         componentMovedOrResized (*component, true, true);
  81
  82         if (component != nullptr)
  83             componentVisibilityChanged (*component);
  84     }
  85 }
  86
  87 void ComponentMovementWatcher::componentMovedOrResized (Component&, bool wasMoved, bool wasResized)
  88 {
  89     if (component != nullptr)
  90     {
  91         if (wasMoved)
  92         {
  93             const Point<int> pos (component->getTopLevelComponent()->getLocalPoint (component, Point<int>()));
  94
  95             wasMoved = lastBounds.getPosition() != pos;
  96             lastBounds.setPosition (pos);
  97         }
  98
  99         wasResized = (lastBounds.getWidth() != component->getWidth() || lastBounds.getHeight() != component->getHeight());
 100         lastBounds.setSize (component->getWidth(), component->getHeight());
 101
 102         if (wasMoved || wasResized)
 103             componentMovedOrResized (wasMoved, wasResized);
 104     }
 105 }
 106
 107 void ComponentMovementWatcher::componentBeingDeleted (Component& comp)
 108 {
 109     registeredParentComps.removeValue (&comp);
 110
 111     if (component == &comp)
 112         unregister();
 113 }
 114
 115 void ComponentMovementWatcher::componentVisibilityChanged (Component&)
 116 {
 117     if (component != nullptr)
 118     {
 119         const bool isShowingNow = component->isShowing();
 120
 121         if (wasShowing != isShowingNow)
 122         {
 123             wasShowing = isShowingNow;
 124             componentVisibilityChanged();
 125         }
 126     }
 127 }
 128
 129 void ComponentMovementWatcher::registerWithParentComps()
 130 {
 131     Component* p = component->getParentComponent();
 132
 133     while (p != nullptr)
 134     {
 135         p->addComponentListener (this);
 136         registeredParentComps.add (p);
 137         p = p->getParentComponent();
 138     }
 139 }
 140
 141 void ComponentMovementWatcher::unregister()
 142 {
 143     for (int i = registeredParentComps.size(); --i >= 0;)
 144         registeredParentComps.getUnchecked(i)->removeComponentListener (this);
 145
 146     registeredParentComps.clear();
 147 }
 148
 149
 150 END_JUCE_NAMESPACE