nullpointerexception - Android Canvas drawcolor throws Null pointer exception -


developing small android game (2.1 till 4.2 support), below code throws java.lang.nullpointerexception exception at

canvas.drawcolor((0xffaaaaaa);

public class maingamepanel extends surfaceview implements surfaceholder.callback {  public void render(canvas canvas) {                       canvas.drawcolor(0xffaaaaaa);             droid.draw(canvas);      } }

here stack trace

java.lang.nullpointerexception @ com.rdx.play.maingamepanel.render(maingamepanel.java:186) @ com.rdx.play.mainthread.run(mainthread.java:54)

the exception inconsistent, might causing issue?

many thanks.

surfaceholder.lockcanvas() allowed return null (cos thread doesn't have same lifetime surface). bet aren't handling possibility in thread function.


Comments

Post a Comment

Popular posts from this blog

ios - iPhone/iPad different view orientations in different views , and apple approval process -

i force app's home screen portrait , other views landscape. apple rejects app if this? if not , how force first screen launch in portrait mode? , force other screens launch in landscape. this not duplicate question search every possible answer in website. i force app's home screen portrait , other views landscape. apple rejects app if this? no apple not reject app this. have lot of apps doesn't support orientation. forcing on 1 screen won't cause app reject. if not , how force first screen launch in portrait mode? , force other screens launch in landscape. can on write : -(nsuinteger)supportedinterfaceorientations; function.
Read more

monitor web browser programmatically in Android? -

i've got tricky question here. need users make payment bank (namely barclaycard) in uk. so, have https url , add parameters (such amount pay, order reference, etc) url, start http connection intent.actionview, redirect user browser can enter credit card details on bank's webpage , make payment our account successfully. far ? the code use below (i changed values privacy reasons) problem is, need app when user has completed/failed/cancelled payment. barclaycardautomatically redirects particular url when payment has succeeded, 1 if failed. there no way of knowing when barclaycard payment has succeeded go android app somehow ? button cardbutton = (button) findviewbyid(r.id.card_button); cardbutton.setonclicklistener(new view.onclicklistener() { @override public void onclick(view arg0) { string prehashstring = new string(); string prohashstring = new string(); string shapassphrase = new string(); shapassphrase = "gsvth£h70zkh...
Read more

c# - Using multiple datasets in RDLC -

i working on rdlc reports, , reports work fine. got stuck when added 1 more dataset rdlc file. on adding dataset, added data source well. ran project, , report no more working giving error: a data source instance has not been supplied data source can 1 please guide me on steps take in order use multiple datasets. using visual studio 2012. multiple datasources added follows: reportviewer1.localreport.datasources.add(rds); reportviewer1.localreport.datasources.add(rds1); refer link: http://www.c-sharpcorner.com/uploadfile/robo60/standalonerdlcreports11142007183516pm/standalonerdlcreports.aspx all parts covered in this. also refer usefull discussion: http://forums.asp.net/t/1241964.aspx
Read more