From 0ddf722e08a5f18c115c84cd83e78b5c7ef8a3a3 Mon Sep 17 00:00:00 2001
From: Jekyll Wu <adaptee@gmail.com>
Date: Sat, 27 Aug 2011 00:10:58 +0800
Subject: [PATCH] Disable clear & reset actions when the secondary screen is in
 use.

BUG:204741
FIXED-IN: 4.8
---
 src/Emulation.cpp         |  7 +++++++
 src/Emulation.h           |  9 +++++++++
 src/Session.cpp           |  8 ++++++++
 src/Session.h             | 13 +++++++++++++
 src/SessionController.cpp | 11 +++++++++++
 src/SessionController.h   |  5 +++++
 src/ViewManager.cpp       |  2 ++
 7 files changed, 55 insertions(+)

diff --git a/src/Emulation.cpp b/src/Emulation.cpp
index 30edd6d16..5473f9d0a 100644
--- a/src/Emulation.cpp
+++ b/src/Emulation.cpp
@@ -99,6 +99,11 @@ ScreenWindow* Emulation::createWindow()
     return window;
 }
 
+void Emulation::checkScreenInUse()
+{
+    emit primaryScreenInUse( _currentScreen == _screen[0] );
+}
+
 Emulation::~Emulation()
 {
     QListIterator<ScreenWindow*> windowIter(_windows);
@@ -122,6 +127,8 @@ void Emulation::setScreen(int n)
         // tell all windows onto this emulation to switch to the newly active screen
         foreach(ScreenWindow* window,_windows)
             window->setScreen(_currentScreen);
+
+        checkScreenInUse();
     }
 }
 
diff --git a/src/Emulation.h b/src/Emulation.h
index cb5fbcfa8..7c22e843c 100644
--- a/src/Emulation.h
+++ b/src/Emulation.h
@@ -404,6 +404,12 @@ signals:
    */
   void flowControlKeyPressed(bool suspendKeyPressed);
 
+  /**
+   * Emitted when the active screen is switched, to indicate whether the primary
+   * screen is in use.
+   */
+  void primaryScreenInUse(bool use);
+
 protected:
   virtual void setMode(int mode) = 0;
   virtual void resetMode(int mode) = 0;
@@ -456,6 +462,9 @@ protected slots:
    */
   void bufferedUpdate();
 
+  // used to emit the primaryScreenInUse(bool) signal
+  void checkScreenInUse();
+
 private slots: 
 
   // triggered by timer, causes the emulation to send an updated screen image to each
diff --git a/src/Session.cpp b/src/Session.cpp
index a9b849097..09f0e4a1a 100644
--- a/src/Session.cpp
+++ b/src/Session.cpp
@@ -140,6 +140,8 @@ Session::Session(QObject* parent) :
            this, SIGNAL(profileChangeCommandReceived(QString)) );
     connect( _emulation, SIGNAL(flowControlKeyPressed(bool)) , this, 
              SLOT(updateFlowControlState(bool)) );
+    connect( _emulation, SIGNAL(primaryScreenInUse(bool)) , this,
+             SLOT(onPrimaryScreenInUse(bool)) );
 
     //create new teletype for I/O with shell process
     openTeletype(-1);
@@ -613,6 +615,12 @@ void Session::updateFlowControlState(bool suspended)
             display->outputSuspended(false);
     }   
 }
+
+void Session::onPrimaryScreenInUse(bool use)
+{
+    emit primaryScreenInUse(use);
+}
+
 void Session::activityStateSet(int state)
 {
     if (state == NOTIFYBELL)
diff --git a/src/Session.h b/src/Session.h
index 2060bb52f..ea2702ecf 100644
--- a/src/Session.h
+++ b/src/Session.h
@@ -576,6 +576,15 @@ signals:
   */
   void flowControlEnabledChanged(bool enabled);
 
+ /**
+  * Emitted when the active screen is swiched, to indicate whether the primary
+  * screen is in use.
+  *
+  * This signal serves as a relayer of Emulation::priamyScreenInUse(bool),
+  * making it usable for higher level component.
+  */
+  void primaryScreenInUse( bool use);
+
 private slots:
   void done(int, QProcess::ExitStatus);
 
@@ -598,6 +607,10 @@ private slots:
 
   void updateFlowControlState(bool suspended);
   void updateWindowSize(int lines, int columns);
+
+  // signal relayer
+  void onPrimaryScreenInUse(bool use);
+
 private:
 
   void updateTerminalSize();
diff --git a/src/SessionController.cpp b/src/SessionController.cpp
index fbb853149..f54892556 100644
--- a/src/SessionController.cpp
+++ b/src/SessionController.cpp
@@ -292,6 +292,17 @@ void SessionController::openUrl( const KUrl& url )
     }
 }
 
+void SessionController::setupPrimaryScreenSpecificActions( bool use)
+{
+    KActionCollection * collection = actionCollection() ;
+    QAction * clearAction = collection->action("clear-history");
+    QAction * resetAction = collection->action("clear-history-and-reset");
+
+    // these actions are meaningful only when primary screen is used.
+    clearAction->setEnabled(use);
+    resetAction->setEnabled(use);
+}
+
 bool SessionController::eventFilter(QObject* watched , QEvent* event)
 {
     if ( watched == _view )
diff --git a/src/SessionController.h b/src/SessionController.h
index 8ae33cfdb..6cc492f72 100644
--- a/src/SessionController.h
+++ b/src/SessionController.h
@@ -158,6 +158,11 @@ public slots:
      */
     void openUrl( const KUrl& url ); 
 
+    /**
+     * update actions which are meaningful only when rimary screen is in use.
+     */
+    void setupPrimaryScreenSpecificActions( bool use);
+
 private slots:
     // menu item handlers
     void openBrowser();
diff --git a/src/ViewManager.cpp b/src/ViewManager.cpp
index 26d427031..9e61f193b 100644
--- a/src/ViewManager.cpp
+++ b/src/ViewManager.cpp
@@ -520,6 +520,8 @@ SessionController* ViewManager::createController(Session* session , TerminalDisp
     SessionController* controller = new SessionController(session,view,this);
     connect( controller , SIGNAL(focused(SessionController*)) , this , SLOT(controllerChanged(SessionController*)) );
     connect( session , SIGNAL(destroyed()) , controller , SLOT(deleteLater()) );
+    connect( session , SIGNAL(primaryScreenInUse(bool)) ,
+             controller , SLOT(setupPrimaryScreenSpecificActions(bool)) );
     connect( view , SIGNAL(destroyed()) , controller , SLOT(deleteLater()) );
 
     // if this is the first controller created then set it as the active controller