QML UI: use stackView to show sub windows

QML on Android doesn't support multiple windows, so dialogs that work on
the desktop are not a good solution on Android. A much more natural way to
present sub windows is a stackView.

In order to do this Preferences needs to be an item and the structure of
the ApplicationWindow needs to change a bit.

This also removes the hard coded sizes and instead tries to design this in
a resolution independent manner.

The diff appears larger than the actual change because of an increase of
indentation for the ApplicationWindow content.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

qt-mobile/Preferences.qml

@@ -5,7 +5,7 @@ import QtQuick.Dialogs 1.2
 import QtQuick.Layouts 1.1
 import org.subsurfacedivelog.mobile 1.0
 
-Window {
+Item {
 	id: loginWindow
 
 	signal accept
@@ -14,8 +14,6 @@ Window {
 	property string password: password.text;
 	property bool issave: savePassword.checked;
 
-	flags: Qt.Dialog
-	modality: Qt.WindowModal
 	GridLayout {
 		columns: 2
 		anchors.centerIn: parent
@@ -66,8 +64,7 @@ Window {
 					manager.cloudUserName = login.text
 					manager.cloudPassword = password.text
 					manager.savePreferences()
-					loginWindow.close();
-					loginWindow.accept();
+					stackView.pop()
 				}
 			}
 		}
@@ -80,7 +77,7 @@ Window {
 				text: "Cancel"
 
 				onClicked: {
-					loginWindow.close();
+					stackView.pop();
 				}
 			}
 		}

qt-mobile/main.qml

@@ -10,31 +10,39 @@ ApplicationWindow {
 	property bool fullscreen: true
 	visible: true
 
-	QMLManager {
-		id: manager
-	}
-
-	Preferences {
-		id: prefsWindow
+	StackView {
+		id: stackView
+		anchors.fill: parent
+		focus: true
+		Keys.onReleased: if (event.key == Qt.Key_Back && stackView.depth > 1) {
+					 stackView.pop()
+					 event.accepted = true;
 				 }
+		initialItem: Item {
+			width: parent.width
+			height: parent.height
 
 			ColumnLayout {
-		id: layout
+				id: awLayout
 				anchors.fill: parent
-		spacing: 4
-
+				spacing: prefsButton.height * 0.1
 				Rectangle {
 					id: topPart
-			height: 35
+					Layout.minimumHeight: prefsButton.height * 1.2
 					Layout.fillWidth: true
-			Layout.maximumHeight: 35
+					anchors.bottom: detailsPage.top
+					anchors.bottomMargin: prefsButton.height * 0.1
 
 					RowLayout {
+						anchors.bottom: topPart.bottom
+						anchors.bottomMargin: prefsButton.height * 0.1
+						anchors.left: topPart.left
+						anchors.leftMargin: prefsButton.height * 0.1
 						Button {
 							id: prefsButton
 							text: "Preferences"
 							onClicked: {
-						prefsWindow.show()
+								stackView.push(prefsWindow)
 							}
 						}
 
@@ -53,9 +61,6 @@ ApplicationWindow {
 					id: detailsPage
 					Layout.fillHeight: true
 					Layout.fillWidth: true
-			Layout.minimumWidth: 100
-			Layout.preferredHeight: 400
-			Layout.preferredWidth: 200
 
 					DiveList {
 						anchors.fill: detailsPage
@@ -64,4 +69,16 @@ ApplicationWindow {
 				}
 
 			}
+		}
+	}
+
+	QMLManager {
+		id: manager
+	}
+
+	Preferences {
+		id: prefsWindow
+		visible: false
+	}
+
 }