Solved Creating an object of QVideoWidget closes my mediaplayer app .

[umutgurbuz]

Hi guys, I am trying the make a mediaplayer app that has the basic mediaplayer features.
It is all fine when dealing with mp3 files . I am using QMediaPlayer and QMediaPlaylist in my cpp code . I have a login page main.qml and when user id and password is correct it launches the mediplayer.qml where i call my cpp functions. The problem is that now i am trying to play a video but if i create an object of QVideoWidget , it causes my mediaplayer.qml not to launch and main.qml to close when i clicked the enter button of my login page. I do not even have to use to QVideoWidget object ,just creating it is enough for this problem to occur. What might be causing this problem. Sorry if I kept it too long .Thanks in advance .

[umutgurbuz]

@sgaist The problem was the QGuiApplication in my main.cpp , i turned it to QApplication and it works fine.

And lastly what should i do to use my applicationwindow as my videowidget. I want my video to play on my app like normal mediaplayers, not to open another window for it. Thanks for your kind effort.

[jsulm]

@umutgurbuz said in Creating an object of QVideoWidget closes my mediaplayer app .:

just creating it is enough for this problem to occur

Can you show how you create it?
Are there any warnings/errors in the console when running the app?

[umutgurbuz]

 QVideoWidget *vw = new QVideoWidget;

This is how i create it. There is no error or warning. I am creating it in my header file and now i realized if i create it in my cpp file it does not even launches main.qml(still no error or warnings)

[jsulm]

@umutgurbuz said in Creating an object of QVideoWidget closes my mediaplayer app .:

QVideoWidget *vw = new QVideoWidget;

This creates a local variable which is destroyed when it goes out of scope...

[umutgurbuz]

Now , I am creating it in the function that i am using it . I can see the list in my mediplayer.qml and pick the media that i want to play . Now , it closes when i click on the media name.

[SGaist]

Hi,

You should share more of your code. It's currently next to impossible to find out what is happening based only on your explanation.

[umutgurbuz]

Yes you are right , I should have thought of that .
This is the function in my mediaplayer.cpp
:```

  void Mediaplayer::playvideo(int num)
     {   
  flag=1;
  vidplaylist->setCurrentIndex(num);
  if(player->state()==QMediaPlayer::PlayingState)
  {
      player->stop();
  }
  QVideoWidget vw ;
  player->setVideoOutput(&vw);
  vw.setGeometry(100,100,640,360);
  vw.show();
  vidplayer->play();
  }

this is my main.qml

import QtQuick 2.0
import QtQuick.Controls 2.3
import qt.player 1.0
import QtQuick.Window 2.10
import idpasswd.qt 1.0
ApplicationWindow {
    id: root
    width: 640
    height: 480
    visible: true
    title:("Mediaplayer Login Page")

    Idpasswd {
        id: id
    }
    Idpasswd {
        id: passwd
    }

    Button {
        x: 40
        y: 318
        width: 97
        height: 36
        text: qsTr("Guest")
        onClicked: {
        var component = Qt.createComponent("guest.qml");
        newone = component.createObject(rect);
        newone.show();
        }
    }

    TextField {

        anchors.verticalCenterOffset: -133
        anchors.horizontalCenterOffset: -180
        placeholderText: qsTr("User name")
        anchors.centerIn: parent
        onTextChanged: id.userName = text
    }
    TextField {
        x: 40
        y: 167

        placeholderText: qsTr("Password")
        anchors.horizontalCenter:parent
        onTextChanged: id.password=text
    }

    Rectangle{
        x: 40
        y: 256
        width:97
        height:36
        id: rect
        Button{
        text: qsTr("Enter")
        anchors.fill: parent
        property variant newone;  
            onClicked: {                
               if(id.checkLogin(id.userName,id.password))
               {
                   var component = Qt.createComponent("mediaplayer.qml");
                   newone = component.createObject(rect);
                   newone.show();
                }
               else
               {
                   console.log("Invalid id or password")
               }             
            }
        }
}

    Button{
        x: 167
        y: 256
        text: qsTr("Change Password")
        font.pointSize: 8
        font.family: "Times New Roman"
        focusPolicy: Qt.NoFocus
        width:97
        height:36
    }

}

            

And this is where i am trying to call the function in mediaplayer.qml.

     ScrollView {
              id:mp4scroll
              x: 50
              y:96
              width: 250; height: 200
              visible:false
              ListView {
                  id:listmp4
                  model: player.createplaylistmp4()
                  delegate: ItemDelegate {
                      id:listdelegmp4
                      text: player.sendNamesvid(index)
                      font.pixelSize: 10
                      onClicked: player.playvideo(index), playimage.source="qrc:/pause.png"
                  }
              }
          }

[JonB]

@umutgurbuz said in Creating an object of QVideoWidget closes my mediaplayer app .:

QVideoWidget vw ;
player->setVideoOutput(&vw);
vw.setGeometry(100,100,640,360);
vw.show();
vidplayer->play();
}

I don't use any of this, so I hope I'm right:
That QVideoWidget vw goes out of scope at the }. player->setVideoOutput(&vw); still references it. Kerplunk?

[umutgurbuz]

@jonb I do not understand what you mean. What should i try ?

[SGaist]

What @JonB means is that the lifetime of your QVideoWidget ends at the end of the method because you are creating it on the stack. Thus you are passing a pointer to an object that gets destroyed.

The question is: why are you re-creating the QVideoWidget each time ?

[umutgurbuz]

I was actually creating it in my header file once but i wanted to see what changes when i create it in my method. The result is that when i create it in my header, it closes when i click the enter button that launches my mediaplayer.qml. When i create QVideoWidget in my method, it can launch my mediaplayer.qml but this time it closes when i pick the video on the window(scroll view list view part). What is the right thing to do ? Where and how should i create it ?

[umutgurbuz]

@sgaist The problem was the QGuiApplication in my main.cpp , i turned it to QApplication and it works fine.

And lastly what should i do to use my applicationwindow as my videowidget. I want my video to play on my app like normal mediaplayers, not to open another window for it. Thanks for your kind effort.

[umutgurbuz]

This post is deleted!