Error: Cannot assign [undefined] to QUrl

sierdzio

Perhaps items really is empty or undefined? Try printing it with console.log().

Naveen_D

@sierdzio i tried this with a small example, what i am doing is on a click of button i am trying to play the song. here i am not getting any error but i didn't get output also, on click of button nothing happens.. i tried printing using console, here is the minimal code which i am trying...

import QtQuick 2.6
import QtQuick.Controls 1.5
import QtQuick.Controls.Styles 1.4
import QtQuick.Layouts 1.1
import QtMultimedia 5.0
import Qt.labs.folderlistmodel 1.0

ApplicationWindow {
    visible: true
    width: 640
    height: 480

    MediaPlayer {
        id: player
    }

    Item {
        id: playerLogic

        property int index: -1
        property MediaPlayer mediaplayer: player
        property FolderListModel items: FolderListModel{
            folder: "Songs"
            nameFilters: ["*.mp3"]
        }

        function init(){
            console.log("Entered init function")
            if(mediaplayer.PlayingState===1)
            {
                console.log("playing state is 1")
                mediaplayer.pause();
            }else if(mediaplayer.PlayingState===2){
                console.log("playing state is 2")
                mediaplayer.play();
            } else {
                console.log("calling index function")
                setIndex(0);
            }
        }

        function setIndex(i){
            console.log("entered setindex function")
            index= i
            if(index<0 || index> items.count){
                console.log("checking if condition")
                index=-1;
                mediaplayer.source="";
            }else {
                console.log("else part")
                mediaplayer.source=items.get(index,"filePath");
                console.log("before playing the song")
                mediaplayer.play();
            }
        }
    }

    Button{
        id: playpausebutton
        anchors.centerIn: parent
        width: 100
        height: 80
        text: "PlayMusic"
        state: "none"
        style: ButtonStyle{
            background: Rectangle{
                id: buttonbackground
                implicitHeight: parent.height
                implicitWidth: parent.width
                color: "#00bcd4"
                opacity: playpausebutton.pressed ? 0.5: 1.0
                radius: 5
            }
        }
        MouseArea {
            id: buttonmousearea
            anchors.fill: parent
            onClicked: playerLogic.init()
        }
    }

}

output :
QML debugging is enabled. Only use this in a safe environment.
libva info: VA-API version 0.37.0
libva info: va_getDriverName() returns 0
libva info: Trying to open /usr/lib/x86_64-linux-gnu/dri/fglrx_drv_video.so
libva info: va_openDriver() returns -1
libva info: VA-API version 0.37.0
libva info: va_getDriverName() returns 0
libva info: Trying to open /usr/lib/x86_64-linux-gnu/dri/fglrx_drv_video.so
libva info: va_openDriver() returns -1
libva info: VA-API version 0.37.0
libva info: va_getDriverName() returns 0
libva info: Trying to open /usr/lib/x86_64-linux-gnu/dri/fglrx_drv_video.so
libva info: va_openDriver() returns -1
libva info: VA-API version 0.37.0
libva info: va_getDriverName() returns 0
libva info: Trying to open /usr/lib/x86_64-linux-gnu/dri/fglrx_drv_video.so
libva info: va_openDriver() returns -1
qml: Entered init function
qml: calling index function
qml: entered setindex function
qml: else part
qml: before playing the song
qml: Entered init function
qml: calling index function
qml: entered setindex function
qml: else part
qml: before playing the song

sierdzio

No, I mean print the items.

               console.log("Items:" + items)
                mediaplayer.source=items.get(index,"filePath");
                console.log("before playing the song")
                mediaplayer.play();

Looks like something is bad in your env, too, see these lines: libva info: va_openDriver() returns -1 seems like the audio driver is not working?

Naveen_D

@sierdzio When i print the items, i get the following output:
qml: items are: QQuickFolderListModel(0xf12ac0)

sierdzio

Ah, not very helpful. Try printing out all items in a loop, then.

Naveen_D

@sierdzio i am not getting how to print the items in foldermodellist i tried with the following code but didn't get output:

for (var j=0; j<items.count;j++){
                    console.log("items"+ items(j))
                }

is this the correct way ?

sierdzio

Almost :-)

for (var j=0; j<items.count;j++){
    console.log("item:"+ items.get(index,"filePath"))
}

Maybe that will help us pinpoint the issue.

Naveen_D

@sierdzio Hi, i tried printing those items, but i am getting the same error again (Error: Cannot assign [undefined] to QUrl), also when i try to print those items, i am not able to find the auto get method for items(i.e items.get() method) and it is not entering the for loop.
what can be the possible solution? thanks

sierdzio

Please try:

print items.count and items.get(0, "filePath")
rewrite items to be a normal QML component and not a property (see example code in the docs) and see if it works
make sure the path is OK :-)

Naveen_D

@sierdzio

print items.count and items.get(0, "filePath")

output:
qml: items count >> 0
qml: items at 0 position >> undefined

rewrite items to be a normal QML component and not a property (see example code in the docs) and see if it works

i made the following changes, pls rectify if there is any mistake

FolderListModel{
            id: items
            folder: "/home/ubuntu/Documents/Sample_Examples_Qt_Qml/DummyMusicPlayer/Songs"
            nameFilters: ["*.mp3"]
        }

after making changes i am getting the following output:

qml: Entered init function
qml: calling index function
qml: entered setindex function
qml: else part
qml: items count >> 0
qml: items at 0 position >> undefined
qrc:/main.qml:58: Error: Cannot assign [undefined] to QUrl

sierdzio

OK, so now at least we know this:

issue is not related to QtMultimedia
issue is with FolderListModel
"Cannot assign [undefined]" is there, because items is empty (no .mp3 files are detected in Songs folder)

Try using URL instead of path:

folder: "file:///home/ubuntu/Documents/Sample_Examples_Qt_Qml/DummyMusicPlayer/Songs"

Relative and absolute paths should work, but apparently something fails here. Also, of course, please make sure there are some MP3s in that dir.

Naveen_D

@sierdzio yup, now its detecting the mp3 files, i am getting the following output,

qml: Entered init function
qml: calling index function
qml: entered setindex function
qml: else part
qml: items count >> 5
qml: items at 0>> /home/ubuntu/Documents/Sample_Examples_Qt_Qml/DummyMusicPlayer/Songs/Cinema_Choopista-StarMusiQ.Com.mp3
qml: before playing the song

But i am not sure the song is playing or not, because i am not getting sound. Does it require anything else for this?

sierdzio

Nice, I'm glad to hear that problem is solved.

@Naveen_D said in Error: Cannot assign [undefined] to QUrl:

But i am not sure the song is playing or not, because i am not getting sound. Does it require anything else for this?

I'm not familiar with QtMultimedia, I can't help here unfortunately. My first guesses are:

check if you have gstreamer 0.1 installed
check if you have mp3 codecs installed (mp3lame or something)
check some QtMultimedia examples in Qt Creator - does the sound work there?

Naveen_D

Thanks for the information,
But previously i had tried to play songs using this and it was working fine, i found out that when i directly give source in the media player and play it is working fine the song is playing, but when i give the folderlistmodel path using the get method it is not working.
also i tried to print the path, when i give the direct source path, the path printed is the URL path but when it takes through the folderlistmodel, it is the normal path

i.e Direct source path with song if i give, the path set is :
"file:///home/ubuntu/Documents/Sample_Examples_Qt_Qml/DummyMusicPlayer/Songs/David Guetta - Love Don't Let Me Go (Memorax Remix) [FREE].mp3"

and through folderlistmodel with the index, the path set is :
"/home/ubuntu/Documents/Sample_Examples_Qt_Qml/DummyMusicPlayer/Songs/David Guetta - Love Don't Let Me Go (Memorax Remix) [FREE].mp3"

Can anyone please suggest the possible solution.
Thanks

Naveen_D

I have solved the issue,

mediaplayer.source=items.get(index,"filePath");

I was using filePath, instead of this i used fileURL, the issue got resolved.

@sierdzio thanks alot for your help.

Thanks

sierdzio

Cool, good to hear that :) Please mark the topic as solved, too.