App crashes when the popup window is called

Question

The popup window has to be shown when the app is started. The function that calls the popup window is located in the OnCreate() method. When I start debugging the app it constantly crashes.

    public void ShowPopup() {

       dialog.setContentView(R.layout.mainactiv);
       dialog.getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
       dialog.show();
    }

And this is the error message:

java.lang.RuntimeException: Unable to start activity ComponentInfo

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.app.Dialog.setContentView(int)' on a null object reference

Can you please initialize your dialog before setContentView? — Ali Yucel Akgul, Jun 07 '19 at 17:07
@AliYucelAkgul I am newbie to android development, can you please tell me how to initialize the dialog? — vitrd, Jun 07 '19 at 17:11

score 0 · Accepted Answer · answered Jun 07 '19 at 17:12

You need to first initialize the dialog before using it.

public void ShowPopup() {
    dialog = new Dialog(this);    // Initialize dialog before use
    dialog.setContentView(R.layout.mainactiv);
    dialog.getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
    dialog.show();
}

App crashes when the popup window is called

1 Answers1