fix: open shortcuts window on correct screen

corrections:
- open on the same display,
- center to the parent window,
- has dimensions not more than the parent window

Change-Id: I2315d62fef6d830b6957770807ace462fbb77901
Gitlab: #774

src/app/mainview/MainView.qml

@@ -606,7 +606,7 @@ Rectangle {
         sequence: "F10"
         context: Qt.ApplicationShortcut
         onActivated: {
-            KeyboardShortcutTableCreation.createKeyboardShortcutTableWindowObject()
+            KeyboardShortcutTableCreation.createKeyboardShortcutTableWindowObject(appWindow)
             KeyboardShortcutTableCreation.showKeyboardShortcutTableWindow()
         }
     }

src/app/mainview/components/WelcomePage.qml

@@ -241,7 +241,7 @@ Rectangle {
                     toolTipText: JamiStrings.keyboardShortcuts
 
                     onClicked:  {
-                        KeyboardShortcutTableCreation.createKeyboardShortcutTableWindowObject()
+                        KeyboardShortcutTableCreation.createKeyboardShortcutTableWindowObject(appWindow)
                         KeyboardShortcutTableCreation.showKeyboardShortcutTableWindow()
                     }
                 }

src/app/mainview/js/keyboardshortcuttablecreation.js

@@ -19,12 +19,14 @@
 // Global select screen window component, object variable for creation.
 var keyboardShortcutTableWindowComponent
 var keyboardShortcutTableWindowObject
+var mainWindow
 
-function createKeyboardShortcutTableWindowObject() {
+function createKeyboardShortcutTableWindowObject(appWindow) {
     if (keyboardShortcutTableWindowObject)
         return
     keyboardShortcutTableWindowComponent = Qt.createComponent(
                 "../components/KeyboardShortcutTable.qml")
+    mainWindow = appWindow
     if (keyboardShortcutTableWindowComponent.status === Component.Ready)
         finishCreation()
     else if (keyboardShortcutTableWindowComponent.status === Component.Error)
@@ -45,12 +47,13 @@ function finishCreation() {
 
 function showKeyboardShortcutTableWindow() {
     keyboardShortcutTableWindowObject.show()
+    var centerX = mainWindow.x + mainWindow.width / 2
+    var centerY = mainWindow.y + mainWindow.height / 2
 
-    var screen = keyboardShortcutTableWindowObject.screen
-    keyboardShortcutTableWindowObject.x = screen.virtualX +
-            (screen.width - keyboardShortcutTableWindowObject.width) / 2
-    keyboardShortcutTableWindowObject.y = screen.virtualY +
-            (screen.height - keyboardShortcutTableWindowObject.height) / 2
+    keyboardShortcutTableWindowObject.width = 0.75 * appWindow.width
+    keyboardShortcutTableWindowObject.height = 0.75 * appWindow.height
+    keyboardShortcutTableWindowObject.x = centerX - keyboardShortcutTableWindowObject.width / 2
+    keyboardShortcutTableWindowObject.y = centerY - keyboardShortcutTableWindowObject.height / 2
 }
 
 // Destroy and reset selectScreenWindowObject when window is closed.