add bottom buttons

bottombuttongroup.cpp

@@ -0,0 +1,42 @@
+#include "bottombuttongroup.h"
+
+#include <QPushButton>
+#include <QVBoxLayout>
+#include <QDebug>
+
+BottomButtonGroup::BottomButtonGroup(QWidget *parent)
+    : QGroupBox (parent)
+{
+    QHBoxLayout * mainLayout = new QHBoxLayout(this);
+    mainLayout->setSizeConstraint(QLayout::SetFixedSize);
+    this->setLayout(mainLayout);
+    this->setSizePolicy(QSizePolicy::Minimum, QSizePolicy::Minimum);
+    this->setStyleSheet("BottomButtonGroup {"
+                        "border: 1px solid gray;"
+                        "border-top-left-radius: 10px;"
+                        "border-top-right-radius: 10px;"
+                        "border-bottom: none;"
+                        "background-color:rgba(0,0,0,180)"
+                        "}"
+                        "QPushButton {"
+                        "background-color:rgba(225,255,255,0);"
+                        "color: white;"
+                        "}");
+
+    auto newBtn = [](QString text) -> QPushButton * {
+        QPushButton * btn = new QPushButton(text);
+        btn->setFixedSize(40, 40);
+        return btn;
+    };
+    addButton(newBtn("1:1"));
+    addButton(newBtn("Full"));
+    addButton(newBtn("Zoom+"));
+    addButton(newBtn("Zoom-"));
+    addButton(newBtn("Rorate"));
+}
+
+void BottomButtonGroup::addButton(QAbstractButton *button)
+{
+    layout()->addWidget(button);
+    updateGeometry();
+}