accelBubble Tutorial

[guestu]

I have tried to start mobile development with the "Creating a Mobile Qt Application" Tutorial. I have installed Qt Creator 4.9.2 on Windows 10 (1903). I connected a Android Device (Wiko Pulp, Android 5.1) with my Computer and compiled the project (after solving a few problems - qmake.conf). When I execute the project, it is installed on my Android device. But the bubble does not move. In the "output of application" tab the is an error: "W/libaccelbubble.so(18015): qrc:/main.qml:115: ReferenceError: mainWindow is not defined"

There is an example accelBubble also in the Qt 5.13.0 directory without pages. This examples runs without problems, but I want to understand, why the tutorial example does not work.

[JKSH]

Hi @guestu, and welcome!

@guestu said in accelBubble Tutorial:

qrc:/main.qml:115: ReferenceError: mainWindow is not defined

The error message tells you that Line #115 contains a reference to mainWindow, but this ID does not exist.

It is like an undefined variable in C++.

[guestu]

@jksh
Thank you,
the problem I had, was that I didn't know how to announce the property "mainWindow" in the main.qml. With your answer I changed

          Page1Form {
              bubble {
                  id: bubble
                  centerX: mainWindow.width / 2
                  centerY: mainWindow.height / 2
                  bubbleCenter: bubble.width / 2
                  x: bubble.centerX - bubble.bubbleCenter 
...

to

          Page1Form {
              mainWindow {
                id: mainWindow
              }

              bubble {
                  id: bubble
                  centerX: mainWindow.width / 2
                  centerY: mainWindow.height / 2
                  bubbleCenter: bubble.width / 2
                  x: bubble.centerX - bubble.bubbleCenter
...

Now the mainWindow is know and the application is running as expected.
Thank you very much.