Hack workaround to 5.9 android FileDialog Qt bug

https://bugreports.qt.io/browse/QTBUG-61424

HackAndroidFileDialog.qrc

+<RCC>
+    <qresource prefix="/qml">
+        <file alias="QGroundControl/Controls/HackFileDialog.qml">src/QmlControls/HackAndroidFileDialog.qml</file>
+    </qresource>
+</RCC>

HackFileDialog.qrc

+<RCC>
+    <qresource prefix="/qml">
+        <file alias="QGroundControl/Controls/HackFileDialog.qml">src/QmlControls/HackFileDialog.qml</file>
+    </qresource>
+</RCC>

qgroundcontrol.pro

@@ -13,8 +13,8 @@ exists($${OUT_PWD}/qgroundcontrol.pro) {
 
 message(Qt version $$[QT_VERSION])
 
-!equals(QT_MAJOR_VERSION, 5) | !greaterThan(QT_MINOR_VERSION, 4) {
-    error("Unsupported Qt version, 5.5+ is required")
+!equals(QT_MAJOR_VERSION, 5) | !greaterThan(QT_MINOR_VERSION, 6) {
+    error("Unsupported Qt version, 5.7+ is required")
 }
 
 include(QGCCommon.pri)
@@ -288,6 +288,15 @@ CustomBuild {
         $$PWD/qgcresources.qrc
 }
 
+# On Qt 5.9 android versions there is the following bug: https://bugreports.qt.io/browse/QTBUG-61424
+# This prevents FileDialog from being used. So we have a temp hack workaround for it which just no-ops
+# the FileDialog fallback mechanism on android 5.9 builds.
+equals(QT_MAJOR_VERSION, 5):equals(QT_MINOR_VERSION, 9):AndroidBuild {
+    RESOURCES += $$PWD/HackAndroidFileDialog.qrc
+} else {
+    RESOURCES += $$PWD/HackFileDialog.qrc
+}
+
 #
 # Main QGroundControl portion of project file
 #

src/QmlControls/HackAndroidFileDialog.qml

+import QtQuick          2.3
+import QtQuick.Dialogs  1.2
+
+// On Qt 5.9 android versions there is the following bug: https://bugreports.qt.io/browse/QTBUG-61424
+// This prevents FileDialog from being used. So we have a temp hack workaround for it which just no-ops
+// the FileDialog fallback mechanism on android 5.9 builds.
+
+Item {
+    property var folder
+    property var nameFilters
+    property var title
+    property var selectExisting
+    property var selectMultiple
+    property var selectFolder
+
+    signal accepted
+    signal rejected
+}

src/QmlControls/HackFileDialog.qml

+import QtQuick          2.3
+import QtQuick.Dialogs  1.2
+
+// On Qt 5.9 android versions there is the following bug: https://bugreports.qt.io/browse/QTBUG-61424
+// This prevents FileDialog from being used. So we have a temp hack workaround for it which just no-ops
+// the FileDialog fallback mechanism on android 5.9 builds.
+
+FileDialog {
+}

src/QmlControls/QGCFileDialog.qml

@@ -66,7 +66,10 @@ Item {
     QGCFileDialogController { id: controller }
     QGCPalette { id: qgcPal; colorGroupEnabled: true }
 
-    FileDialog {
+    // On Qt 5.9 android versions there is the following bug: https://bugreports.qt.io/browse/QTBUG-61424
+    // This prevents FileDialog from being used. So we have a temp hack workaround for it which just no-ops
+    // the FileDialog fallback mechanism on android 5.9 builds.
+    HackFileDialog {
         id:             fullFileDialog
         folder:         "file://" + _root.folder
         nameFilters:    _root.nameFilters ? _root.nameFilters : []

src/QmlControls/QGroundControl.Controls.qmldir

@@ -13,6 +13,7 @@ FlightModeDropdown      1.0 FlightModeDropdown.qml
 FlightModeMenu          1.0 FlightModeMenu.qml
 GeoFenceEditor          1.0 GeoFenceEditor.qml
 GeoFenceMapVisuals      1.0 GeoFenceMapVisuals.qml
+HackFileDialog          1.0 HackFileDialog.qml
 IndicatorButton         1.0 IndicatorButton.qml
 JoystickThumbPad        1.0 JoystickThumbPad.qml
 MainToolBar             1.0 MainToolBar.qml