Qt 6.4.2 Android Qml loader issue

[julienchevet]

Qt 6.4.2 QZXing 3.3 Android 11

I placed the Camera and the QZXingFilter in a Component, loaded by a Loader. If I pass it to the Loader directly in the sourceComponent property, the camera is loaded when the application starts and the QZXingFilter decodes the QRCodes, it works fine.

But if I load it after a button click, for example, I get a black screen and these errors:

I ViewRootImpl@4d42ac6[QtActivity]: ViewPostIme pointer 0 D InputMethodManager: HSIFW - flag : 0 I InputMethodManager: hideSoftInputFromWindow ignore mServedView == null or mServedView.getWindowToken() != windowToken, mServedView :DecorView@68adeb5[QtActivity] I ViewRootImpl@4d42ac6[QtActivity]: ViewPostIme pointer 1 D SensorManager: registerListener :: 11, lsm6dsm Accelerometer Non-wakeup, 200000, 0, android.view.OrientationEventListener$SensorEventListenerImpl@d52e84d W Gralloc4: allocator 3.x is not supported W Gralloc3: allocator 3.x is not supported W [SurfaceTexture-4-28300-0] bindTextureImage: clearing GL error: 0x500 D QZXingFilter error: Cant create image file to process. D QZXingFilter error: Cant create image file to process. D QZXingFilter error: Cant create image file to process. D QZXingFilter error: Cant create image file to process. D QZXingFilter error: Cant create image file to process. D QZXingFilter error: Cant create image file to process. D QZXingFilter error: Cant create image file to process. D QZXingFilter error: Cant create image file to process. D QZXingFilter error: Cant create image file to process.

Here is a simple code to reproduce:

import QtQuick.Window
import QtQuick.Controls
import QtMultimedia
import QZXing

Window {
    id: window
    width: 640
    height: 480
    visible: true
    
    
    Button {
        anchors.centerIn: parent
        text: "Load"
        onClicked: cameraLoader.sourceComponent = cameraComponent
    }
    
    Loader {
        id: cameraLoader
        anchors.fill: parent
        //        sourceComponent: cameraComponent
    }
    
    Component {
        id: cameraComponent
        
        Item {
            Camera {
                id:camera
                active: true
                focusMode: Camera.FocusModeAutoNear
            }
            
            CaptureSession {
                camera: camera
                videoOutput: videoOutput
            }
            
            VideoOutput
            {
                id: videoOutput
                anchors.fill: parent
                fillMode: VideoOutput.Stretch
                
                property double captureRectStartFactorX: 0.25
                property double captureRectStartFactorY: 0.25
                property double captureRectFactorWidth: 0.5
                property double captureRectFactorHeight: 0.5
                
                Rectangle {
                    id: captureZone
                    color: "red"
                    opacity: 0.2
                    width: parent.width * parent.captureRectFactorWidth
                    height: parent.height * parent.captureRectFactorHeight
                    x: parent.width * parent.captureRectStartFactorX
                    y: parent.height * parent.captureRectStartFactorY
                }
            }
            
            QZXingFilter
            {
                id: zxingFilter
                videoSink: videoOutput.videoSink
                
                captureRect: {
                    videoOutput.sourceRect;
                    return Qt.rect(videoOutput.sourceRect.width * videoOutput.captureRectStartFactorX,
                                   videoOutput.sourceRect.height * videoOutput.captureRectStartFactorY,
                                   videoOutput.sourceRect.width * videoOutput.captureRectFactorWidth,
                                   videoOutput.sourceRect.height * videoOutput.captureRectFactorHeight)
                }
                
                decoder {
                    enabledDecoders: QZXing.DecoderFormat_EAN_13 | QZXing.DecoderFormat_CODE_39 | QZXing.DecoderFormat_QR_CODE
                    
                    onTagFound: {
                        console.log(tag + " | " + decoder.foundedFormat() + " | " + decoder.charSet());
                        
                        window.detectedTags++;
                        window.lastTag = tag;
                    }
                    
                    tryHarder: false
                }
                
                property int framesDecoded: 0
                property real timePerFrameDecode: 0
                
                onDecodingFinished: function (succeeded, decodeTime)
                {
                    timePerFrameDecode = (decodeTime + framesDecoded * timePerFrameDecode) / (framesDecoded + 1);
                    framesDecoded++;
                    if(succeeded)
                        console.log("frame finished: " + succeeded, decodeTime, timePerFrameDecode, framesDecoded);
                }
            }
        }
    }
}