Calling Java class from Qt (like notification example)

[Qojote]

The notification example of Qt shows how to call java code and it works like charme.
Now when i take the same code and copy it into my project, the app crashes.
Thanks to debug prints i know that the java function notify is called but getSystemService hangs.

package org.tud.qpcam;

import android.app.Notification;
import android.app.NotificationManager;
import android.content.Context;

public class AndroidWifiHandler extends org.qtproject.qt5.android.bindings.QtActivity
{
    private static NotificationManager m_notificationManager;
    private static Notification.Builder m_builder;
    private static AndroidWifiHandler m_instance;

    public AndroidWifiHandler()
    {
        m_instance = this;
    }

    public static void notify(String s)
    {
        System.out.println(s);

        if (m_notificationManager == null)
        {
            System.out.println(m_instance);
            m_notificationManager = (NotificationManager)m_instance.getSystemService(Context.NOTIFICATION_SERVICE);
            System.out.println(m_notificationManager);
            m_builder = new Notification.Builder(m_instance);
            m_builder.setSmallIcon(R.drawable.icon);
            m_builder.setContentTitle("A message from Qt!");
        }

        m_builder.setContentText(s);
        m_notificationManager.notify(1, m_builder.build());
    }
}

and calling function code is:

 QAndroidJniObject javaNotification = QAndroidJniObject::fromString(m_notification);
 QAndroidJniObject::callStaticMethod<void>("org/tud/qpcam/AndroidWifiHandler",
                                       "notify",
                                       "(Ljava/lang/String;)V",
                                       javaNotification.object<jstring>());

What could be the reason for that? I took the source file an copied it and i changed the package name.

EDIT:
The problem is that m_instance is NULL, so getSystemService fails.

Best regards

[patrikd]

Hi Qojote,
not sure why its not working, but try following:
Imports:

import org.qtproject.qt5.android.bindings.QtApplication;
import org.qtproject.qt5.android.bindings.QtActivity;
import org.qtproject.qt5.android.QtNative;

public class AndroidWifiHandler extends QtActivity 

and don't forget to update your manifest:

<application android:name="org.qtproject.qt5.android.bindings.QtApplication" ...
<activity android:name="org.qtproject.qt5.android.bindings.AndroidWifiHandler"....

hope this helps,
patrik

[Qojote]

Hi patrik,

Thanks a lot. The manifest entry for activity android:name had to be changed. Now it works like expected.