Description: Allow plugin's "static" configration change
 This is patch 1/4 adding autoexpansion support to the spacer plugin.
Author: Palo Kisa <palo.kisa@gmail.com>
Origin: upstream
Bug: https://github.com/lxqt/lxqt/issues/1038
Applied-Upstream: commit:6fbe184
Last-Update: 2018-08-16
--- a/panel/ilxqtpanel.h
+++ b/panel/ilxqtpanel.h
@@ -110,6 +110,16 @@ public:
      *
      */
     virtual void willShowWindow(QWidget * w) = 0;
+
+    /*!
+     * \brief By calling this function, a plugin notifies the panel about change of it's "static"
+     * configuration
+     *
+     * \param plugin the changed plugin
+     *
+     * \sa ILXQtPanelPlugin::isSeparate(), ILXQtPanelPlugin::isExpandable
+     */
+    virtual void pluginFlagsChanged(const ILXQtPanelPlugin * plugin) = 0;
 };
 
 #endif // ILXQTPANEL_H
--- a/panel/ilxqtpanelplugin.h
+++ b/panel/ilxqtpanelplugin.h
@@ -196,6 +196,17 @@ public:
         mPanel->willShowWindow(w);
     }
 
+    /*!
+     * \brief By calling this function, a plugin notifies the panel about change of it's "static"
+     * configuration
+     *
+     * \sa isSeparate(), isExpandable
+     */
+    inline void pluginFlagsChanged()
+    {
+        mPanel->pluginFlagsChanged(this);
+    }
+
     virtual bool isSeparate() const { return false;  }
     virtual bool isExpandable() const { return false; }
 private:
--- a/panel/lxqtpanel.cpp
+++ b/panel/lxqtpanel.cpp
@@ -1225,6 +1225,14 @@ void LXQtPanel::willShowWindow(QWidget *
 /************************************************
 
  ************************************************/
+void LXQtPanel::pluginFlagsChanged(const ILXQtPanelPlugin * /*plugin*/)
+{
+    mLayout->rebuild();
+}
+
+/************************************************
+
+ ************************************************/
 QString LXQtPanel::qssPosition() const
 {
     return positionToStr(position());
--- a/panel/lxqtpanel.h
+++ b/panel/lxqtpanel.h
@@ -146,6 +146,7 @@ public:
     QRect calculatePopupWindowPos(QPoint const & absolutePos, QSize const & windowSize) const override;
     QRect calculatePopupWindowPos(const ILXQtPanelPlugin *plugin, const QSize &windowSize) const override;
     void willShowWindow(QWidget * w) override;
+    void pluginFlagsChanged(const ILXQtPanelPlugin * plugin) override;
     // ........ end of ILXQtPanel overrides
 
     /**
--- a/panel/lxqtpanellayout.cpp
+++ b/panel/lxqtpanellayout.cpp
@@ -946,6 +946,16 @@ void LXQtPanelLayout::setLineCount(int v
 /************************************************
 
  ************************************************/
+void LXQtPanelLayout::rebuild()
+{
+    mLeftGrid->rebuild();
+    mRightGrid->rebuild();
+}
+
+
+/************************************************
+
+ ************************************************/
 int LXQtPanelLayout::lineSize() const
 {
     return mLeftGrid->lineSize();
--- a/panel/lxqtpanellayout.h
+++ b/panel/lxqtpanellayout.h
@@ -73,6 +73,10 @@ public:
     ILXQtPanel::Position position() const { return mPosition; }
     void setPosition(ILXQtPanel::Position value);
 
+    /*! \brief Force the layout to re-read items/plugins "static" configuration
+     */
+    void rebuild();
+
     static bool itemIsSeparate(QLayoutItem *item);
 signals:
     void pluginMoved(Plugin * plugin);