objective c - NSPanel not showing -

i have created class toolpanelcontroller subclass of nswindowcontroller , .xib file named toolpanel when start app toolpanel don't show up. file's owner class set toolpanelcontroller panel delegate file's owner , window connected file's owner. how can set panel show when app starts running?

toolpanelcontroller.h:

#import <cocoa/cocoa.h>  @interface toolpanelcontroller : nswindowcontroller  {     iboutlet nspanel *toolpanel; } + (id)sharedtoolpalettecontroller; @end 

toolpanelcontroller.m:

#import "toolpanelcontroller.h"  @interface toolpanelcontroller ()  @end  @implementation toolpanelcontroller  + (id)sharedtoolpalettecontroller {     static toolpanelcontroller *sharedtoolpalettecontroller = nil;  if (!sharedtoolpalettecontroller) {     sharedtoolpalettecontroller = [[toolpanelcontroller allocwithzone:null] init]; }  return sharedtoolpalettecontroller; }  - (id)initwithwindow:(nswindow *)window {      self = [self initwithwindownibname:@"toolpanel"];     if (self) {         [self setwindowframeautosavename:@"toolpanel"];         [(nspanel *)[self window] orderfront:self];     }     return self;  }  - (void)windowdidload {      [super windowdidload];      // implement method handle initialization after window controller's window has been loaded nib file. }  @end