Big rewrite to the internals of modal components, with a new class ModalComponentManager. This now lets you use modal components asynchronously, providing an object which will receive a callback when they are dismissed, rather than using a blocking event loop. ComboBoxes and some other components now show their popups asynchronously.

src/gui/components/juce_ModalComponentManager.cpp

@@ -0,0 +1,267 @@
+/*
+  ==============================================================================
+
+   This file is part of the JUCE library - "Jules' Utility Class Extensions"
+   Copyright 2004-10 by Raw Material Software Ltd.
+
+  ------------------------------------------------------------------------------
+
+   JUCE can be redistributed and/or modified under the terms of the GNU General
+   Public License (Version 2), as published by the Free Software Foundation.
+   A copy of the license is included in the JUCE distribution, or can be found
+   online at www.gnu.org/licenses.
+
+   JUCE is distributed in the hope that it will be useful, but WITHOUT ANY
+   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+   A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+  ------------------------------------------------------------------------------
+
+   To release a closed-source product which uses JUCE, commercial licenses are
+   available: visit www.rawmaterialsoftware.com/juce for more information.
+
+  ==============================================================================
+*/
+
+#include "../../core/juce_StandardHeader.h"
+
+BEGIN_JUCE_NAMESPACE
+
+#include "juce_Component.h"
+#include "juce_ModalComponentManager.h"
+#include "../../events/juce_MessageManager.h"
+#include "../../application/juce_Application.h"
+
+
+//==============================================================================
+class ModalComponentManager::ModalItem  : public ComponentListener
+{
+public:
+    ModalItem (Component* const comp, Callback* const callback)
+        : component (comp), returnValue (0), isActive (true), isDeleted (false)
+    {
+        if (callback != 0)
+            callbacks.add (callback);
+
+        jassert (comp != 0);
+        component->addComponentListener (this);
+    }
+
+    ~ModalItem()
+    {
+        if (! isDeleted)
+            component->removeComponentListener (this);
+    }
+
+    void componentBeingDeleted (Component&)
+    {
+        isDeleted = true;
+        cancel();
+    }
+
+    void componentVisibilityChanged (Component&)
+    {
+        if (! component->isShowing())
+            cancel();
+    }
+
+    void componentParentHierarchyChanged (Component&)
+    {
+        if (! component->isShowing())
+            cancel();
+    }
+
+    void cancel()
+    {
+        if (isActive)
+        {
+            isActive = false;
+            ModalComponentManager::getInstance()->triggerAsyncUpdate();
+        }
+    }
+
+    Component* component;
+    OwnedArray<Callback> callbacks;
+    int returnValue;
+    bool isActive, isDeleted;
+
+private:
+    ModalItem (const ModalItem&);
+    ModalItem& operator= (const ModalItem&);
+};
+
+//==============================================================================
+ModalComponentManager::ModalComponentManager()
+{
+}
+
+ModalComponentManager::~ModalComponentManager()
+{
+    clearSingletonInstance();
+}
+
+juce_ImplementSingleton_SingleThreaded (ModalComponentManager);
+
+
+//==============================================================================
+void ModalComponentManager::startModal (Component* component, Callback* callback)
+{
+    if (component != 0)
+        stack.add (new ModalItem (component, callback));
+}
+
+void ModalComponentManager::attachCallback (Component* component, Callback* callback)
+{
+    if (callback != 0)
+    {
+        ScopedPointer<Callback> callbackDeleter (callback);
+
+        for (int i = stack.size(); --i >= 0;)
+        {
+            ModalItem* const item = stack.getUnchecked(i);
+
+            if (item->component == component)
+            {
+                item->callbacks.add (callback);
+                callbackDeleter.release();
+                break;
+            }
+        }
+    }
+}
+
+void ModalComponentManager::endModal (Component* component)
+{
+    for (int i = stack.size(); --i >= 0;)
+    {
+        ModalItem* const item = stack.getUnchecked(i);
+
+        if (item->component == component)
+            item->cancel();
+    }
+}
+
+void ModalComponentManager::endModal (Component* component, int returnValue)
+{
+    for (int i = stack.size(); --i >= 0;)
+    {
+        ModalItem* const item = stack.getUnchecked(i);
+
+        if (item->component == component)
+        {
+            item->returnValue = returnValue;
+            item->cancel();
+        }
+    }
+}
+
+int ModalComponentManager::getNumModalComponents() const
+{
+    int n = 0;
+    for (int i = 0; i < stack.size(); ++i)
+        if (stack.getUnchecked(i)->isActive)
+            ++n;
+
+    return n;
+}
+
+Component* ModalComponentManager::getModalComponent (const int index) const
+{
+    int n = 0;
+    for (int i = stack.size(); --i >= 0;)
+    {
+        const ModalItem* const item = stack.getUnchecked(i);
+        if (item->isActive)
+            if (n++ == index)
+                return item->component;
+    }
+
+    return 0;
+}
+
+bool ModalComponentManager::isModal (Component* const comp) const
+{
+    for (int i = stack.size(); --i >= 0;)
+    {
+        const ModalItem* const item = stack.getUnchecked(i);
+        if (item->isActive && item->component == comp)
+            return true;
+    }
+
+    return false;
+}
+
+bool ModalComponentManager::isFrontModalComponent (Component* const comp) const
+{
+    return comp == getModalComponent (0);
+}
+
+void ModalComponentManager::handleAsyncUpdate()
+{
+    for (int i = stack.size(); --i >= 0;)
+    {
+        const ModalItem* const item = stack.getUnchecked(i);
+        if (! item->isActive)
+        {
+            for (int j = item->callbacks.size(); --j >= 0;)
+                item->callbacks.getUnchecked(j)->modalStateFinished (item->returnValue);
+
+            stack.remove (i);
+        }
+    }
+}
+
+class ModalComponentManager::ReturnValueRetriever     : public ModalComponentManager::Callback
+{
+public:
+    ReturnValueRetriever (int& value_, bool& finished_) : value (value_), finished (finished_) {}
+    ~ReturnValueRetriever() {}
+
+    void modalStateFinished (int returnValue)
+    {
+        finished = true;
+        value = returnValue;
+    }
+
+private:
+    int& value;
+    bool& finished;
+
+    ReturnValueRetriever (const ReturnValueRetriever&);
+    ReturnValueRetriever& operator= (const ReturnValueRetriever&);
+};
+
+int ModalComponentManager::runEventLoopForCurrentComponent()
+{
+    // This can only be run from the message thread!
+    jassert (MessageManager::getInstance()->isThisTheMessageThread());
+
+    Component* currentlyModal = getModalComponent (0);
+
+    if (currentlyModal == 0)
+        return 0;
+
+    Component::SafePointer<Component> prevFocused (Component::getCurrentlyFocusedComponent());
+
+    int returnValue = 0;
+    bool finished = false;
+    attachCallback (currentlyModal, new ReturnValueRetriever (returnValue, finished));
+
+    JUCE_TRY
+    {
+        while (! finished)
+        {
+            if  (! MessageManager::getInstance()->runDispatchLoopUntil (20))
+                break;
+        }
+    }
+    JUCE_CATCH_EXCEPTION
+
+    if (prevFocused != 0)
+        prevFocused->grabKeyboardFocus();
+
+    return returnValue;
+}
+
+
+END_JUCE_NAMESPACE