qml: UI only. Added FileDialog and the initial custom datadir functio…

…nality without wiring

src/qml/components/StorageLocations.qml

@@ -5,6 +5,10 @@
 import QtQuick 2.15
 import QtQuick.Controls 2.15
 import QtQuick.Layouts 1.15
+import QtQuick.Dialogs 1.3
+
+import org.bitcoincore.qt 1.0
+
 import "../controls"
 
 ColumnLayout {
@@ -25,5 +29,21 @@ ColumnLayout {
         ButtonGroup.group: group
         text: qsTr("Custom")
         description: qsTr("Choose the directory and storage device.")
+        onClicked: fileDialog.open()
+    }
+    FileDialog {
+        id: fileDialog
+        selectFolder: true
+        folder: optionsModel.getDefaultDataDirectory
+        onAccepted: {
+            optionsModel.setCustomDataDirString(fileDialog.fileUrls[0].toString())
+            var customDataDir = fileDialog.fileUrl.toString();
+            if (customDataDir !== "") {
+            optionsModel.setCustomDataDirArgs(customDataDir);
+            }
+        }
+        onRejected: {
+            console.log("Custom datadir selection canceled")
+        }
     }
-}
+}