Apps NullPointerException AlertDialog.Builder

[deathsonic18]

Hi everyone

I've been looking into this for a couple of hours and changed the code quite a few times however the nullpointerexception error is still appearing

The problem is occuring when my "WorkOn" class calls another class called "Dialogs"

So this is my WorkOn Class

public Context context = this;
    Dialogs saveDialog = new Dialogs(context);

//constructor
    public WorkOn(Context context) {
    this.context = context;

}

    public void OnTime(View v) {


            saveDialog.WorkOnSavedDialog(v);


        }


    });


}

This is my Dialogs class

public class Dialogs extends AppCompatActivity  {




public Context context = this;
//constructor

public Dialogs(Context context) {
    this.context = context;


}

public void WorkOnSavedDialog(View v) {

    AlertDialog.Builder alert = new AlertDialog.Builder(Dialogs.this);


    alert.setTitle("Work On File Saved");
    alert.setMessage("[Displaying for Test] Work On File Saved");
    alert.setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int which) {
                    // continue with delete
                }
            });
    alert.setNegativeButton(android.R.string.no, new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int which) {
                    // do nothing
                }
            });
    alert.setIcon(android.R.drawable.ic_dialog_alert);
    alert.show();
}
}

The nullpointer excpection is happening because of

AlertDialog.Builder alert = new AlertDialog.Builder(Dialogs.this);

do you have any idea why this is happening?

 

[Deleted User]

You need to post the stack trace from your Logcat output

 

[deathsonic18]

My logcat is

08-01 10:20:36.156 5739-5739/geepool.workonworkoff E/AndroidRuntime: FATAL EXCEPTION: main
                                                                     java.lang.NullPointerException
                                                                         at android.content.ContextWrapper.getApplicationInfo(ContextWrapper.java:132)
                                                                         at android.view.ContextThemeWrapper.getTheme(ContextThemeWrapper.java:65)
                                                                         at android.support.v7.app.AlertDialog.resolveDialogTheme(AlertDialog.java:111)
                                                                         at android.support.v7.app.AlertDialog.access$000(AlertDialog.java:70)
                                                                         at android.support.v7.app.AlertDialog$Builder.<init>(AlertDialog.java:291)
                                                                         at geepool.workonworkoff.Dialogs.WorkOnSavedDialog(Dialogs.java:25)
                                                                         at geepool.workonworkoff.WorkOn$1.onClick(WorkOn.java:99)
                                                                         at android.view.View.performClick(View.java:4084)
                                                                         at android.view.View$PerformClick.run(View.java:16966)
                                                                         at android.os.Handler.handleCallback(Handler.java:615)
                                                                         at android.os.Handler.dispatchMessage(Handler.java:92)
                                                                         at android.os.Looper.loop(Looper.java:137)
                                                                         at android.app.ActivityThread.main(ActivityThread.java:4745)
                                                                         at java.lang.reflect.Method.invokeNative(Native Method)
                                                                         at java.lang.reflect.Method.invoke(Method.java:511)
                                                                         at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
                                                                         at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
                                                                         at dalvik.system.NativeStart.main(Native Method)

thanks once again

 

[Deleted User]

AlertDialog.Builder() takes a Context (an Activity object). Try using

new AlertDialog.Builder(getActivity())

http://www.tutorialspoint.com/android/android_alert_dialoges.htm

Alternatively, you could use a reference to your main Activity, like this

public void WorkOnSavedDialog(View v, Context activity) {
    AlertDialog.Builder alert = new AlertDialog.Builder(activity);

 

[Unforgiven]

Application Development thread moved to the Development forum for better exposure.