diff --git a/RedPandaIDE/settings.cpp b/RedPandaIDE/settings.cpp
index 4a748c73..ddc2e072 100644
--- a/RedPandaIDE/settings.cpp
+++ b/RedPandaIDE/settings.cpp
@@ -1033,6 +1033,9 @@ void Settings::CompilerSets::deleteSet(int index)
     for (int i=index;i<mList.size();i++) {
         saveSet(i);
     }
+    if (mDefaultIndex>=mList.size()) {
+        mDefaultIndex = mList.size()-1;
+    }
 }
 
 Settings::CompilerSetList &Settings::CompilerSets::list()
diff --git a/RedPandaIDE/settingsdialog/compilersetdirectorieswidget.cpp b/RedPandaIDE/settingsdialog/compilersetdirectorieswidget.cpp
index f72386da..3c7268d4 100644
--- a/RedPandaIDE/settingsdialog/compilersetdirectorieswidget.cpp
+++ b/RedPandaIDE/settingsdialog/compilersetdirectorieswidget.cpp
@@ -1,7 +1,9 @@
 #include "compilersetdirectorieswidget.h"
 #include "ui_compilersetdirectorieswidget.h"
 
+#include <QFileDialog>
 #include <QStringListModel>
+#include <QDebug>
 
 CompilerSetDirectoriesWidget::CompilerSetDirectoriesWidget(QWidget *parent) :
     QWidget(parent),
@@ -11,6 +13,9 @@ CompilerSetDirectoriesWidget::CompilerSetDirectoriesWidget(QWidget *parent) :
 
     mModel = new CompilerSetDirectoriesWidget::ListModel();
     ui->listView->setModel(mModel);
+    connect(ui->listView->selectionModel(), &QItemSelectionModel::selectionChanged,
+            this, &CompilerSetDirectoriesWidget::selectionChanged);
+    ui->listView->setSelectionMode(QAbstractItemView::SingleSelection);
 }
 
 CompilerSetDirectoriesWidget::~CompilerSetDirectoriesWidget()
@@ -21,6 +26,8 @@ CompilerSetDirectoriesWidget::~CompilerSetDirectoriesWidget()
 void CompilerSetDirectoriesWidget::setDirList(const QStringList &list)
 {
     mModel->setStringList(list);
+    QModelIndexList lst =ui->listView->selectionModel()->selectedIndexes();
+    ui->btnDelete->setEnabled(lst.count()>0);
 }
 
 QStringList CompilerSetDirectoriesWidget::dirList() const
@@ -30,7 +37,49 @@ QStringList CompilerSetDirectoriesWidget::dirList() const
 
 Qt::ItemFlags CompilerSetDirectoriesWidget::ListModel::flags(const QModelIndex &index) const
 {
+    Qt::ItemFlags flags = Qt::NoItemFlags;
     if (index.isValid()) {
-        return Qt::ItemIsEnabled | Qt::ItemIsDragEnabled | Qt::ItemIsEditable | Qt::ItemIsSelectable;
+        flags = Qt::ItemIsEnabled | Qt::ItemIsDragEnabled | Qt::ItemIsEditable | Qt::ItemIsSelectable ;
+    } else if (index.row() ==-1) {
+        // -1 means it's a drop target?
+        flags = Qt::ItemIsDropEnabled;
+    }
+    return flags;
+}
+
+void CompilerSetDirectoriesWidget::on_btnAdd_pressed()
+{
+    QString folder = QFileDialog::getExistingDirectory(this,tr("Choose Folder"));
+    if (!folder.isEmpty()) {
+        int row = mModel->rowCount();
+        mModel->insertRow(row);
+        QModelIndex index= mModel->index(row,0);
+        mModel->setData(index,folder,Qt::DisplayRole);
     }
 }
+
+void CompilerSetDirectoriesWidget::selectionChanged(const QItemSelection &selected, const QItemSelection &deselected)
+{
+    ui->btnDelete->setEnabled(!selected.isEmpty());
+}
+
+void CompilerSetDirectoriesWidget::on_btnDelete_pressed()
+{
+    QModelIndexList lst =ui->listView->selectionModel()->selectedIndexes();
+    if (lst.count()>0) {
+        mModel->removeRow(lst[0].row());
+    }
+}
+
+
+void CompilerSetDirectoriesWidget::on_btnRemoveInvalid_pressed()
+{
+    QStringList lst;
+    for (const QString& folder : dirList() ) {
+        QFileInfo info(folder);
+        if (info.exists() && info.isDir() ) {
+            lst.append(folder);
+        }
+    }
+    setDirList(lst);
+}
diff --git a/RedPandaIDE/settingsdialog/compilersetdirectorieswidget.h b/RedPandaIDE/settingsdialog/compilersetdirectorieswidget.h
index 4491bcb7..102c8b05 100644
--- a/RedPandaIDE/settingsdialog/compilersetdirectorieswidget.h
+++ b/RedPandaIDE/settingsdialog/compilersetdirectorieswidget.h
@@ -8,6 +8,7 @@ namespace Ui {
 class CompilerSetDirectoriesWidget;
 }
 
+class QItemSelection;
 
 class CompilerSetDirectoriesWidget : public QWidget
 {
@@ -24,6 +25,15 @@ public:
     void setDirList(const QStringList& list);
     QStringList dirList() const;
 
+private slots:
+    void on_btnDelete_pressed();
+
+    void on_btnAdd_pressed();
+
+    void selectionChanged(const QItemSelection &selected, const QItemSelection &deselected);
+
+    void on_btnRemoveInvalid_pressed();
+
 private:
     Ui::CompilerSetDirectoriesWidget *ui;
     ListModel* mModel;
diff --git a/RedPandaIDE/settingsdialog/compilersetdirectorieswidget.ui b/RedPandaIDE/settingsdialog/compilersetdirectorieswidget.ui
index c2603fa3..405bf877 100644
--- a/RedPandaIDE/settingsdialog/compilersetdirectorieswidget.ui
+++ b/RedPandaIDE/settingsdialog/compilersetdirectorieswidget.ui
@@ -24,7 +24,7 @@
      </property>
      <layout class="QHBoxLayout" name="horizontalLayout">
       <item>
-       <widget class="QToolButton" name="toolButton">
+       <widget class="QToolButton" name="btnAdd">
         <property name="toolTip">
          <string>Add</string>
         </property>
@@ -37,12 +37,12 @@
          </iconset>
         </property>
         <property name="autoRaise">
-         <bool>true</bool>
+         <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
-       <widget class="QToolButton" name="toolButton_2">
+       <widget class="QToolButton" name="btnDelete">
         <property name="toolTip">
          <string>Delete</string>
         </property>
@@ -55,12 +55,12 @@
          </iconset>
         </property>
         <property name="autoRaise">
-         <bool>true</bool>
+         <bool>false</bool>
         </property>
        </widget>
       </item>
       <item>
-       <widget class="QToolButton" name="toolButton_3">
+       <widget class="QToolButton" name="btnRemoveInvalid">
         <property name="toolTip">
          <string>Remove Invalid</string>
         </property>
@@ -76,7 +76,7 @@
          <enum>Qt::ToolButtonIconOnly</enum>
         </property>
         <property name="autoRaise">
-         <bool>true</bool>
+         <bool>false</bool>
         </property>
        </widget>
       </item>
diff --git a/RedPandaIDE/settingsdialog/compilersetoptionwidget.cpp b/RedPandaIDE/settingsdialog/compilersetoptionwidget.cpp
index df00604f..f42a2c8c 100644
--- a/RedPandaIDE/settingsdialog/compilersetoptionwidget.cpp
+++ b/RedPandaIDE/settingsdialog/compilersetoptionwidget.cpp
@@ -59,7 +59,7 @@ void resetOptionTabs(Settings::PCompilerSet pSet,QTabWidget* pTab)
             pTab->addTab(pWidget,pOption->section);
             pWidget->setLayout(new QGridLayout());
         }
-        QGridLayout *pLayout = (QGridLayout*)pWidget->layout();
+        QGridLayout *pLayout = static_cast<QGridLayout*>(pWidget->layout());
         int row = pLayout->rowCount();
         pLayout->addWidget(new QLabel(pOption->name),row,0);
         QComboBox* pCombo = new QComboBox();
@@ -82,7 +82,7 @@ void resetOptionTabs(Settings::PCompilerSet pSet,QTabWidget* pTab)
     }
     for (int i=0;i<pTab->count();i++) {
         QWidget* pWidget = pTab->widget(i);
-        QGridLayout *pLayout = (QGridLayout*)pWidget->layout();
+        QGridLayout *pLayout = static_cast<QGridLayout*>(pWidget->layout());
         int row = pLayout->rowCount();
         QSpacerItem* horizontalSpacer = new QSpacerItem(10, 100, QSizePolicy::Minimum, QSizePolicy::Expanding);
         pLayout->addItem(horizontalSpacer,row,0);
@@ -112,18 +112,33 @@ static void loadCompilerSetSettings(Settings::PCompilerSet pSet, Ui::CompilerSet
 
 void CompilerSetOptionWidget::doLoad()
 {
+    disconnectInputs();
     ui->cbCompilerSet->clear();
+    if (pSettings->compilerSets().list().size()<=0) {
+        ui->btnRenameCompilerSet->setEnabled(false);
+        ui->btnRemoveCompilerSet->setEnabled(false);
+        return;
+    } else {
+        ui->btnRenameCompilerSet->setEnabled(true);
+        ui->btnRemoveCompilerSet->setEnabled(true);
+    }
     int index=pSettings->compilerSets().defaultIndex();
     for (int i=0;i<pSettings->compilerSets().list().size();i++) {
         ui->cbCompilerSet->addItem(pSettings->compilerSets().list()[i]->name());
     }
+    if (index < 0 || index>=ui->cbCompilerSet->count()) {
+        index = 0;
+    }
     ui->cbCompilerSet->setCurrentIndex(index);
-
-    //reloadCurrentCompilerSet();
+    reloadCurrentCompilerSet();
+    connectInputs();
 }
 
 void CompilerSetOptionWidget::doSave()
 {
+    if (pSettings->compilerSets().list().size()>0) {
+        saveCurrentCompilerSet();
+    }
     pSettings->compilerSets().saveSets();
 }
 
@@ -131,8 +146,11 @@ void CompilerSetOptionWidget::on_cbCompilerSet_currentIndexChanged(int index)
 {
     if (index<0)
         return;
+    setSettingsChanged();
     pSettings->compilerSets().setDefaultIndex(index);
+    disconnectInputs();
     reloadCurrentCompilerSet();
+    connectInputs();
 }
 
 void CompilerSetOptionWidget::reloadCurrentCompilerSet()
@@ -145,7 +163,50 @@ void CompilerSetOptionWidget::reloadCurrentCompilerSet()
     mCIncludeDirWidget->setDirList(pSet->CIncludeDirs());
     mCppIncludeDirWidget->setDirList(pSet->CppIncludeDirs());
 
-    connectInputs();
+}
+
+void CompilerSetOptionWidget::saveCurrentCompilerSet()
+{
+    Settings::PCompilerSet pSet = pSettings->compilerSets().defaultSet();
+
+    pSet->setUseCustomCompileParams(ui->chkUseCustomCompilerParams->isChecked());
+    pSet->setCustomCompileParams(ui->txtCustomCompileParams->toPlainText());
+    pSet->setUseCustomLinkParams(ui->chkUseCustomLinkParams->isChecked());
+    pSet->setCustomLinkParams(ui->txtCustomLinkParams->toPlainText());
+    pSet->setStaticLink(ui->chkStaticLink->isChecked());
+    pSet->setAutoAddCharsetParams(ui->chkAutoAddCharset->isChecked());
+
+    pSet->setCCompiler(ui->txtCCompiler->text());
+    pSet->setCppCompiler(ui->txtCppCompiler->text());
+    pSet->setMake(ui->txtMake->text());
+    pSet->setDebugger(ui->txtDebugger->text());
+    pSet->setResourceCompiler(ui->txtResourceCompiler->text());
+    pSet->setProfiler(ui->txtProfiler->text());
+
+    pSet->binDirs()=mBinDirWidget->dirList();
+
+    pSet->libDirs()=mLibDirWidget->dirList();
+    pSet->CIncludeDirs()=mCIncludeDirWidget->dirList();
+    pSet->CppIncludeDirs()=mCppIncludeDirWidget->dirList();
+
+    //read values in the options widget
+    QTabWidget* pTab = ui->optionTabs;
+    for (int i=0;i<pTab->count();i++) {
+        QString section = pTab->tabText(i);
+        QWidget* pWidget = pTab->widget(i);
+        QGridLayout* pLayout = static_cast<QGridLayout*>(pWidget->layout());
+        if (pLayout != nullptr) {
+            for (int j=1;j<pLayout->rowCount()-1;j++) {
+                QString name = static_cast<QLabel *>(pLayout->itemAtPosition(j,0)->widget())->text();
+                QComboBox* pCombo = static_cast<QComboBox *>(pLayout->itemAtPosition(j,1)->widget());
+                for (PCompilerOption pOption: pSet->options()) {
+                    if (pOption->section == section && pOption->name == name) {
+                        pOption->value = pCombo->currentIndex();
+                    }
+                }
+            }
+        }
+    }
 }
 
 void CompilerSetOptionWidget::on_btnFindCompilers_pressed()
@@ -180,8 +241,15 @@ void CompilerSetOptionWidget::on_btnAddCompilerSetByFolder_pressed()
 
 void CompilerSetOptionWidget::on_btnRenameCompilerSet_pressed()
 {
-    QString name = QInputDialog::getText(this,tr("Compiler Set Name"),tr("New name"));
+    QString name = QInputDialog::getText(this,tr("Compiler Set Name"),tr("New name"),QLineEdit::Normal,
+                                         pSettings->compilerSets().defaultSet()->name());
     if (!name.isEmpty())
         pSettings->compilerSets().defaultSet()->setName(name);
     doLoad();
 }
+
+void CompilerSetOptionWidget::on_btnRemoveCompilerSet_pressed()
+{
+    pSettings->compilerSets().deleteSet(ui->cbCompilerSet->currentIndex());
+    doLoad();
+}
diff --git a/RedPandaIDE/settingsdialog/compilersetoptionwidget.h b/RedPandaIDE/settingsdialog/compilersetoptionwidget.h
index 5f961150..ae1a5438 100644
--- a/RedPandaIDE/settingsdialog/compilersetoptionwidget.h
+++ b/RedPandaIDE/settingsdialog/compilersetoptionwidget.h
@@ -31,6 +31,7 @@ protected:
     void doSave() override;
 private:
     void reloadCurrentCompilerSet();
+    void saveCurrentCompilerSet();
 
 private slots:
     void on_cbCompilerSet_currentIndexChanged(int index);
@@ -38,6 +39,7 @@ private slots:
     void on_btnAddBlankCompilerSet_pressed();
     void on_btnAddCompilerSetByFolder_pressed();
     void on_btnRenameCompilerSet_pressed();
+    void on_btnRemoveCompilerSet_pressed();
 };
 
 #endif // COMPILERSETOPTIONWIDGET_H
diff --git a/RedPandaIDE/settingsdialog/settingsdialog.cpp b/RedPandaIDE/settingsdialog/settingsdialog.cpp
index a702df98..576b62ee 100644
--- a/RedPandaIDE/settingsdialog/settingsdialog.cpp
+++ b/RedPandaIDE/settingsdialog/settingsdialog.cpp
@@ -90,7 +90,7 @@ void SettingsDialog::on_btnOk_pressed()
 
 void SettingsDialog::saveCurrentPageSettings(bool confirm)
 {
-    if (ui->scrollArea->widget()!=ui->scrollAreaWidgetContents)
+    if (ui->scrollArea->widget()==ui->scrollAreaWidgetContents)
         return;
     SettingsWidget* pWidget = (SettingsWidget*) ui->scrollArea->widget();
     if (!pWidget->isSettingsChanged())
@@ -99,8 +99,8 @@ void SettingsDialog::saveCurrentPageSettings(bool confirm)
         if (QMessageBox::information(this,tr("Save Changes"),
                tr("There are changes in the settings, do you want to save them before swtich to other page?"),
                QMessageBox::Yes, QMessageBox::No)!=QMessageBox::Yes) {
-        return;
+            return;
+        }
     }
     pWidget->save();
-    ui->btnApply->setEnabled(false);
 }
diff --git a/RedPandaIDE/settingsdialog/settingswidget.cpp b/RedPandaIDE/settingsdialog/settingswidget.cpp
index f9dfc85b..8d5d7b94 100644
--- a/RedPandaIDE/settingsdialog/settingswidget.cpp
+++ b/RedPandaIDE/settingsdialog/settingswidget.cpp
@@ -24,13 +24,32 @@ void SettingsWidget::init()
 void SettingsWidget::load()
 {
     doLoad();
-    mSettingsChanged = false;
+    clearSettingsChanged();
 }
 
 void SettingsWidget::save()
 {
     doSave();
-    mSettingsChanged = false;
+    clearSettingsChanged();
+}
+
+void SettingsWidget::connectAbstractItemView(QAbstractItemView *pView)
+{
+    connect(pView->model(),&QAbstractItemModel::rowsInserted,this,&SettingsWidget::setSettingsChanged);
+    connect(pView->model(),&QAbstractItemModel::rowsMoved,this,&SettingsWidget::setSettingsChanged);
+    connect(pView->model(),&QAbstractItemModel::rowsRemoved,this,&SettingsWidget::setSettingsChanged);
+    connect(pView->model(),&QAbstractItemModel::dataChanged,this,&SettingsWidget::setSettingsChanged);
+    connect(pView->model(),&QAbstractItemModel::modelReset,this,&SettingsWidget::setSettingsChanged);
+}
+
+void SettingsWidget::disconnectAbstractItemView(QAbstractItemView *pView)
+{
+    disconnect(pView->model(),&QAbstractItemModel::rowsInserted,this,&SettingsWidget::setSettingsChanged);
+    disconnect(pView->model(),&QAbstractItemModel::rowsMoved,this,&SettingsWidget::setSettingsChanged);
+    disconnect(pView->model(),&QAbstractItemModel::rowsRemoved,this,&SettingsWidget::setSettingsChanged);
+    disconnect(pView->model(),&QAbstractItemModel::dataChanged,this,&SettingsWidget::setSettingsChanged);
+    disconnect(pView->model(),&QAbstractItemModel::modelReset,this,&SettingsWidget::setSettingsChanged);
+
 }
 
 void SettingsWidget::connectInputs()
@@ -48,11 +67,30 @@ void SettingsWidget::connectInputs()
         connect(p, QOverload<int>::of(&QComboBox::currentIndexChanged) ,this, &SettingsWidget::setSettingsChanged);
     }
     for (QAbstractItemView* p: findChildren<QAbstractItemView*>()) {
-        connect(p, &QAbstractItemView::activated,this, &SettingsWidget::setSettingsChanged);
+        connectAbstractItemView(p);
     }
 
 }
 
+void SettingsWidget::disconnectInputs()
+{
+    for (QLineEdit* p:findChildren<QLineEdit*>()) {
+        disconnect(p, &QLineEdit::textChanged, this, &SettingsWidget::setSettingsChanged);
+    }
+    for (QCheckBox* p:findChildren<QCheckBox*>()) {
+        disconnect(p, &QCheckBox::stateChanged, this, &SettingsWidget::setSettingsChanged);
+    }
+    for (QPlainTextEdit* p:findChildren<QPlainTextEdit*>()) {
+        disconnect(p, &QPlainTextEdit::textChanged, this, &SettingsWidget::setSettingsChanged);
+    }
+    for (QComboBox* p: findChildren<QComboBox*>()) {
+        disconnect(p, QOverload<int>::of(&QComboBox::currentIndexChanged) ,this, &SettingsWidget::setSettingsChanged);
+    }
+    for (QAbstractItemView* p: findChildren<QAbstractItemView*>()) {
+        disconnectAbstractItemView(p);
+    }
+}
+
 const QString &SettingsWidget::group()
 {
     return mGroup;
diff --git a/RedPandaIDE/settingsdialog/settingswidget.h b/RedPandaIDE/settingsdialog/settingswidget.h
index adf790c6..ce43956f 100644
--- a/RedPandaIDE/settingsdialog/settingswidget.h
+++ b/RedPandaIDE/settingsdialog/settingswidget.h
@@ -3,6 +3,7 @@
 
 #include <QWidget>
 
+class QAbstractItemView;
 class SettingsWidget : public QWidget
 {
     Q_OBJECT
@@ -17,16 +18,21 @@ signals:
     void settingsChanged(bool changed);
 
 protected:
-    void connectInputs();
     virtual void doLoad() = 0;
     virtual void doSave() = 0;
+    void connectAbstractItemView(QAbstractItemView* pView);
+    void disconnectAbstractItemView(QAbstractItemView* pView);
 public:
     const QString& group();
     const QString& name();
     bool isSettingsChanged();
+    void connectInputs();
+    void disconnectInputs();
 public slots:
     void setSettingsChanged();
     void clearSettingsChanged();
+private:
+
 private:
     bool mSettingsChanged;
     QString mGroup;