implement qml UI

client/ui/qml/TitleBar.qml

@@ -0,0 +1,37 @@
+import QtQuick 2.12
+import QtQuick.Controls 2.12
+import "./"
+
+Rectangle {
+    id: root
+    color: "#F5F5F5"
+    width: GC.screenWidth
+    height: 30
+    signal closeButtonClicked()
+
+    Button {
+        id: closeButton
+        anchors.verticalCenter: parent.verticalCenter
+        anchors.right: parent.right
+        anchors.rightMargin: 5
+        icon.source: "qrc:/images/close.png"
+        icon.width: 16
+        icon.height: 16
+        width: height
+        height: 20
+        background: Item {}
+        contentItem: Image {
+            source: closeButton.icon.source
+            anchors.fill: closeButton
+            anchors.margins: ms.containsMouse ? 3 : 4
+        }
+        MouseArea {
+            id: ms
+            hoverEnabled: true
+            anchors.fill: closeButton
+        }
+        onClicked: {
+            root.closeButtonClicked()
+        }
+    }
+}