Your 'if' statement isn't correct. You need '==', not a single '='. You are attempting to see if lobster is null, but of course it isn't and never will be. You just assigned it to a newly created Lobster class object right above it. Maybe you want to see if there are no more lobsters in the world, and create another one if there isn't? Then use the following in your world's act method:

I got the error that this(bellow) "could not find method. if (getObjects(Lobster.class).size() == 0)

sure but it is really long do u want your at the places were I put the code you gave me? // set the scolling background image // add other scrollable objects normally // use of the following also adds scrollable objects // the boolean determines scrollable state // use the following for non-scrollable objects prepare(); } /** * Prepare the world for the start of the program. That is: create the initial * objects and add them to the world. */ private void prepare() { Dot dot = new Dot(); addObject(dot, 66, 319); Dot dot2 = new Dot(); addObject(dot2, 64, 346); dot2.setLocation(58, 338); dot.setLocation(59, 319); Dot dot3 = new Dot(); addObject(dot3, 59, 357); Dot dot4 = new Dot(); addObject(dot4, 62, 383); Dot dot5 = new Dot(); addObject(dot5, 98, 388); Dot dot6 = new Dot(); addObject(dot6, 80, 387); Dot dot7 = new Dot(); addObject(dot7, 125, 388); Dot dot8 = new Dot(); addObject(dot8, 146, 382); Dot dot9 = new Dot(); addObject(dot9, 164, 377); Dot dot10 = new Dot(); addObject(dot10, 169, 356); Dot dot11 = new Dot(); addObject(dot11, 169, 325); Dot dot12 = new Dot(); addObject(dot12, 170, 337); Dot dot13 = new Dot(); addObject(dot13, 172, 301); Dot dot14 = new Dot(); addObject(dot14, 172, 278); Dot dot15 = new Dot(); addObject(dot15, 172, 251); Dot dot16 = new Dot(); addObject(dot16, 178, 230); Dot dot17 = new Dot(); addObject(dot17, 61, 284); Dot dot18 = new Dot(); addObject(dot18, 65, 294); Dot dot19 = new Dot(); addObject(dot19, 72, 259); Dot dot20 = new Dot(); addObject(dot20, 79, 228); Dot dot21 = new Dot(); addObject(dot21, 75, 238); Dot dot22 = new Dot(); addObject(dot22, 80, 207); Dot dot23 = new Dot(); addObject(dot23, 83, 186); Dot dot24 = new Dot(); addObject(dot24, 174, 214); Dot dot25 = new Dot(); addObject(dot25, 168, 195); Dot dot26 = new Dot(); addObject(dot26, 170, 175); Dot dot27 = new Dot(); addObject(dot27, 90, 166); Dot dot28 = new Dot(); addObject(dot28, 171, 147); Dot dot29 = new Dot(); addObject(dot29, 176, 157); Dot dot30 = new Dot(); addObject(dot30, 172, 129); Dot dot31 = new Dot(); addObject(dot31, 95, 145); Dot dot32 = new Dot(); addObject(dot32, 102, 123); Dot dot33 = new Dot(); addObject(dot33, 99, 98); dot33.setLocation(96, 98); dot32.setLocation(95, 123); Dot dot34 = new Dot(); addObject(dot34, 99, 76); Dot dot35 = new Dot(); addObject(dot35, 105, 54); Dot dot36 = new Dot(); addObject(dot36, 106, 33); Dot dot37 = new Dot(); addObject(dot37, 113, 13); Dot dot38 = new Dot(); addObject(dot38, 138, 12); Dot dot39 = new Dot(); addObject(dot39, 163, 11); Dot dot40 = new Dot(); addObject(dot40, 187, 10); Dot dot41 = new Dot(); addObject(dot41, 210, 8); Dot dot42 = new Dot(); addObject(dot42, 244, 9); Dot dot43 = new Dot(); addObject(dot43, 228, 7); Dot dot44 = new Dot(); addObject(dot44, 273, 6); Dot dot45 = new Dot(); addObject(dot45, 276, 26); Dot dot46 = new Dot(); addObject(dot46, 279, 47); Dot dot47 = new Dot(); addObject(dot47, 282, 75); Dot dot48 = new Dot(); addObject(dot48, 285, 87); Dot dot49 = new Dot(); addObject(dot49, 288, 105); Dot dot50 = new Dot(); addObject(dot50, 289, 127); Dot dot51 = new Dot(); addObject(dot51, 291, 150); Dot dot52 = new Dot(); addObject(dot52, 294, 176); Dot dot53 = new Dot(); addObject(dot53, 188, 128); Dot dot54 = new Dot(); addObject(dot54, 205, 128); Dot dot55 = new Dot(); addObject(dot55, 216, 150); Dot dot56 = new Dot(); addObject(dot56, 218, 170); Dot dot57 = new Dot(); addObject(dot57, 214, 192); Dot dot58 = new Dot(); addObject(dot58, 219, 221); Dot dot59 = new Dot(); addObject(dot59, 223, 249); Dot dot60 = new Dot(); addObject(dot60, 226, 270); Dot dot61 = new Dot(); addObject(dot61, 227, 307); Dot dot62 = new Dot(); addObject(dot62, 230, 282); Dot dot63 = new Dot(); addObject(dot63, 230, 333); Dot dot64 = new Dot(); addObject(dot64, 227, 353); Dot dot65 = new Dot(); addObject(dot65, 228, 374); Dot dot66 = new Dot(); addObject(dot66, 254, 379); Dot dot67 = new Dot(); addObject(dot67, 275, 375); Dot dot68 = new Dot(); addObject(dot68, 303, 370); Dot dot69 = new Dot(); addObject(dot69, 296, 197); Dot dot70 = new Dot(); addObject(dot70, 298, 212); Dot dot71 = new Dot(); addObject(dot71, 298, 226); Dot dot72 = new Dot(); addObject(dot72, 296, 245); Dot dot73 = new Dot(); addObject(dot73, 298, 267); dot70.setLocation(301, 212); dot72.setLocation(300, 245); dot72.setLocation(303, 245); dot73.setLocation(304, 267); dot71.setLocation(307, 226); Dot dot74 = new Dot(); addObject(dot74, 309, 288); Dot dot75 = new Dot(); addObject(dot75, 314, 304); Dot dot76 = new Dot(); addObject(dot76, 328, 377); Dot dot77 = new Dot(); addObject(dot77, 354, 381); Dot dot78 = new Dot(); addObject(dot78, 336, 300); Dot dot79 = new Dot(); addObject(dot79, 356, 299); Dot dot80 = new Dot(); addObject(dot80, 357, 279); Dot dot81 = new Dot(); addObject(dot81, 361, 259); Dot dot82 = new Dot(); addObject(dot82, 360, 238); Dot dot83 = new Dot(); addObject(dot83, 403, 182); Dot dot84 = new Dot(); addObject(dot84, 382, 184); Dot dot85 = new Dot(); addObject(dot85, 370, 181); Dot dot86 = new Dot(); addObject(dot86, 349, 234); Dot dot87 = new Dot(); addObject(dot87, 329, 233); Dot dot88 = new Dot(); addObject(dot88, 351, 179); Dot dot89 = new Dot(); addObject(dot89, 319, 124); Dot dot90 = new Dot(); addObject(dot90, 347, 124); Dot dot91 = new Dot(); addObject(dot91, 379, 126); Dot dot92 = new Dot(); addObject(dot92, 407, 126); dot88.setLocation(355, 179); removeObject(dot88); dot85.setLocation(370, 178); dot85.setLocation(361, 177); dot85.setLocation(359, 170); dot85.setLocation(358, 171); dot84.setLocation(381, 172); dot83.setLocation(406, 172); dot90.setLocation(347, 110); dot89.setLocation(320, 106); dot91.setLocation(381, 103); dot92.setLocation(410, 105); dot90.setLocation(347, 106); Dot dot93 = new Dot(); addObject(dot93, 378, 374); Dot dot94 = new Dot(); addObject(dot94, 402, 375); Dot dot95 = new Dot(); addObject(dot95, 430, 381); Dot dot96 = new Dot(); addObject(dot96, 458, 381); Dot dot97 = new Dot(); addObject(dot97, 461, 356); Dot dot98 = new Dot(); addObject(dot98, 461, 332); Dot dot99 = new Dot(); addObject(dot99, 459, 304); Dot dot100 = new Dot(); addObject(dot100, 462, 286); Dot dot101 = new Dot(); addObject(dot101, 454, 258); Dot dot102 = new Dot(); addObject(dot102, 451, 236); Dot dot103 = new Dot(); addObject(dot103, 447, 207); Dot dot104 = new Dot(); addObject(dot104, 426, 186); Dot dot105 = new Dot(); addObject(dot105, 412, 78); Dot dot106 = new Dot(); addObject(dot106, 415, 48); Dot dot107 = new Dot(); addObject(dot107, 416, 25); Dot dot108 = new Dot(); addObject(dot108, 444, 25); Dot dot109 = new Dot(); addObject(dot109, 473, 25); Dot dot110 = new Dot(); addObject(dot110, 507, 25); Dot dot111 = new Dot(); addObject(dot111, 544, 31); Dot dot112 = new Dot(); addObject(dot112, 466, 190); Dot dot113 = new Dot(); addObject(dot113, 474, 166); Dot dot114 = new Dot(); addObject(dot114, 478, 134); Dot dot115 = new Dot(); addObject(dot115, 484, 93); Dot dot116 = new Dot(); addObject(dot116, 490, 113); Dot dot117 = new Dot(); addObject(dot117, 519, 98); Dot dot118 = new Dot(); addObject(dot118, 503, 97); Dot dot119 = new Dot(); addObject(dot119, 548, 107); dot110.setLocation(504, 18); dot111.setLocation(540, 16); dot109.setLocation(477, 19); dot109.setLocation(478, 9); dot109.setLocation(476, 9); dot109.setLocation(477, 24); dot108.setLocation(448, 21); dot118.setLocation(542, 131); dot117.setLocation(517, 98); dot117.setLocation(515, 99); dot116.setLocation(482, 110); Dot dot120 = new Dot(); addObject(dot120, 565, 21); dot118.setLocation(572, 108); Dot dot121 = new Dot(); addObject(dot121, 591, 20); Dot dot122 = new Dot(); addObject(dot122, 619, 17); Dot dot123 = new Dot(); addObject(dot123, 642, 14); Dot dot124 = new Dot(); addObject(dot124, 665, 14); Dot dot125 = new Dot(); addObject(dot125, 692, 19); Dot dot126 = new Dot(); addObject(dot126, 606, 110); Dot dot127 = new Dot(); addObject(dot127, 594, 106); Dot dot128 = new Dot(); addObject(dot128, 627, 106); Dot dot129 = new Dot(); addObject(dot129, 657, 107); Dot dot130 = new Dot(); addObject(dot130, 678, 101); Dot dot131 = new Dot(); addObject(dot131, 703, 103); Dot dot132 = new Dot(); addObject(dot132, 725, 108); Dot dot133 = new Dot(); addObject(dot133, 746, 108); Dot dot134 = new Dot(); addObject(dot134, 767, 108); Dot dot135 = new Dot(); addObject(dot135, 789, 108); Dot dot136 = new Dot(); addObject(dot136, 892, 6); Dot dot137 = new Dot(); addObject(dot137, 890, 18); Dot dot138 = new Dot(); addObject(dot138, 893, 37); Dot dot139 = new Dot(); addObject(dot139, 891, 54); Dot dot140 = new Dot(); addObject(dot140, 895, 68); Dot dot141 = new Dot(); addObject(dot141, 898, 94); Dot dot142 = new Dot(); addObject(dot142, 894, 118); Dot dot143 = new Dot(); addObject(dot143, 894, 150); Dot dot144 = new Dot(); addObject(dot144, 893, 176); Dot dot145 = new Dot(); addObject(dot145, 894, 207); Dot dot146 = new Dot(); addObject(dot146, 894, 232); Dot dot147 = new Dot(); addObject(dot147, 717, 9); Dot dot148 = new Dot(); addObject(dot148, 748, 8); Dot dot149 = new Dot(); addObject(dot149, 779, 13); Dot dot150 = new Dot(); addObject(dot150, 808, 15); Dot dot151 = new Dot(); addObject(dot151, 837, 6); Dot dot152 = new Dot(); addObject(dot152, 866, 3); Dot dot153 = new Dot(); addObject(dot153, 793, 131); dot150.setLocation(809, 15); dot149.setLocation(777, 16); dot56.setLocation(209, 170); dot55.setLocation(206, 149); dot58.setLocation(215, 213); dot60.setLocation(225, 269); dot59.setLocation(215, 236); dot62.setLocation(228, 285); dot60.setLocation(216, 258); dot62.setLocation(223, 280); dot62.setLocation(218, 283); dot63.setLocation(222, 335); dot62.setLocation(215, 282); dot63.setLocation(221, 335); dot63.setLocation(216, 334); dot62.setLocation(213, 277); dot62.setLocation(214, 272); dot61.setLocation(227, 310); dot63.setLocation(214, 330); dot62.setLocation(215, 258); dot61.setLocation(215, 291); dot85.setLocation(786, 296); removeObject(dot85); dot153.setLocation(870, 231); Dot dot154 = new Dot(); addObject(dot154, 854, 229); Dot dot155 = new Dot(); addObject(dot155, 838, 230); Dot dot156 = new Dot(); addObject(dot156, 819, 231); Dot dot157 = new Dot(); addObject(dot157, 721, 126); Dot dot158 = new Dot(); addObject(dot158, 748, 126); Dot dot159 = new Dot(); addObject(dot159, 777, 122); dot159.setLocation(790, 132); dot158.setLocation(769, 149); dot157.setLocation(752, 151); Dot dot160 = new Dot(); addObject(dot160, 737, 145); Dot dot161 = new Dot(); addObject(dot161, 737, 172); Dot dot162 = new Dot(); addObject(dot162, 737, 200); Dot dot163 = new Dot(); addObject(dot163, 738, 226); Dot dot164 = new Dot(); addObject(dot164, 744, 253); dot156.setLocation(823, 232); Dot dot165 = new Dot(); addObject(dot165, 746, 270); Dot dot166 = new Dot(); addObject(dot166, 751, 286); Dot dot167 = new Dot(); addObject(dot167, 760, 308); Dot dot168 = new Dot(); addObject(dot168, 784, 310); Dot dot169 = new Dot(); addObject(dot169, 805, 308); Dot dot170 = new Dot(); addObject(dot170, 807, 325); dot170.setLocation(894, 255); Dot dot171 = new Dot(); addObject(dot171, 894, 270); Dot dot172 = new Dot(); addObject(dot172, 897, 286); Dot dot173 = new Dot(); addObject(dot173, 899, 307); Dot dot174 = new Dot(); addObject(dot174, 897, 324); Dot dot175 = new Dot(); addObject(dot175, 895, 347); Dot dot176 = new Dot(); addObject(dot176, 878, 353); Dot dot177 = new Dot(); addObject(dot177, 863, 353); dot177.setLocation(894, 365); dot177.setLocation(892, 366); dot176.setLocation(866, 368); Dot dot178 = new Dot(); addObject(dot178, 846, 357); dot178.setLocation(845, 363); Dot dot179 = new Dot(); addObject(dot179, 822, 358); dot179.setLocation(821, 363); dot179.setLocation(816, 374); dot178.setLocation(839, 375); Dot dot180 = new Dot(); addObject(dot180, 799, 373); Dot dot181 = new Dot(); addObject(dot181, 787, 384); Dot dot182 = new Dot(); addObject(dot182, 774, 395); Dot dot183 = new Dot(); addObject(dot183, 756, 390); Dot dot184 = new Dot(); addObject(dot184, 740, 387); Dot dot185 = new Dot(); addObject(dot185, 719, 383); Dot dot186 = new Dot(); addObject(dot186, 695, 379); Dot dot187 = new Dot(); addObject(dot187, 679, 374); Dot dot188 = new Dot(); addObject(dot188, 740, 307); Dot dot189 = new Dot(); addObject(dot189, 724, 302); Dot dot190 = new Dot(); addObject(dot190, 708, 295); Dot dot191 = new Dot(); addObject(dot191, 692, 288); Dot dot192 = new Dot(); addObject(dot192, 691, 271); Dot dot193 = new Dot(); addObject(dot193, 661, 366); Dot dot194 = new Dot(); addObject(dot194, 650, 349); Dot dot195 = new Dot(); addObject(dot195, 646, 327); dot195.setLocation(637, 328); Dot dot196 = new Dot(); addObject(dot196, 621, 303); Dot dot197 = new Dot(); addObject(dot197, 618, 286); Dot dot198 = new Dot(); addObject(dot198, 621, 264); Dot dot199 = new Dot(); addObject(dot199, 630, 239); Dot dot200 = new Dot(); addObject(dot200, 610, 237); Dot dot201 = new Dot(); addObject(dot201, 589, 237); Dot dot202 = new Dot(); addObject(dot202, 565, 234); Dot dot203 = new Dot(); addObject(dot203, 560, 269); Dot dot204 = new Dot(); addObject(dot204, 562, 255); Dot dot205 = new Dot(); addObject(dot205, 560, 305); Dot dot206 = new Dot(); addObject(dot206, 558, 286); Dot dot207 = new Dot(); addObject(dot207, 545, 316); Dot dot208 = new Dot(); addObject(dot208, 530, 314); Dot dot209 = new Dot(); addObject(dot209, 505, 315); Dot dot210 = new Dot(); addObject(dot210, 492, 314); Dot dot211 = new Dot(); addObject(dot211, 692, 250); Dot dot212 = new Dot(); addObject(dot212, 688, 227); Dot dot213 = new Dot(); addObject(dot213, 688, 203); Dot dot214 = new Dot(); addObject(dot214, 691, 174); Dot dot215 = new Dot(); addObject(dot215, 670, 168); Dot dot216 = new Dot(); addObject(dot216, 653, 170); Dot dot217 = new Dot(); addObject(dot217, 640, 168); Dot dot218 = new Dot(); addObject(dot218, 621, 163); Dot dot219 = new Dot(); addObject(dot219, 602, 165); Dot dot220 = new Dot(); addObject(dot220, 578, 165); Dot dot221 = new Dot(); addObject(dot221, 555, 165); Dot dot222 = new Dot(); addObject(dot222, 528, 164); Dot dot223 = new Dot(); addObject(dot223, 501, 165); dot32.setLocation(85, 119); dot31.setLocation(82, 143); dot27.setLocation(80, 164); dot34.setLocation(90, 76); dot34.setLocation(86, 70); dot33.setLocation(82, 93); dot35.setLocation(94, 47); dot21.setLocation(71, 237); dot19.setLocation(62, 257); dot22.setLocation(74, 201); dot192.setLocation(696, 262); dot191.setLocation(700, 281); dot181.setLocation(787, 391); dot181.setLocation(783, 389); dot180.setLocation(805, 382); dot180.setLocation(805, 385); dot179.setLocation(823, 382); dot178.setLocation(847, 381); dot177.setLocation(893, 368); dot177.setLocation(894, 363); dot177.setLocation(894, 360); dot178.setLocation(845, 378); dot177.setLocation(894, 360); dot177.setLocation(895, 364); dot177.setLocation(890, 367); dot178.setLocation(845, 379); dot177.setLocation(893, 372); dot176.setLocation(869, 381); dot62.setLocation(212, 274); dot61.setLocation(207, 301); dot60.setLocation(210, 256); dot59.setLocation(210, 233); dot117.setLocation(520, 102); dot115.setLocation(497, 100); dot92.setLocation(402, 97); dot201.setLocation(584, 246); dot201.setLocation(584, 246); dot200.setLocation(609, 250); dot200.setLocation(602, 253); removeObject(dot199); dot202.setLocation(567, 250); dot22.setLocation(71, 201); dot21.setLocation(62, 234); dot20.setLocation(67, 215); dot27.setLocation(76, 162); dot23.setLocation(74, 182); dot76.setLocation(334, 386); dot68.setLocation(299, 383); dot68.setLocation(299, 388); dot67.setLocation(276, 386); dot68.setLocation(305, 388); dot86.setLocation(346, 236); dot82.setLocation(353, 243); dot92.setLocation(400, 97); dot91.setLocation(373, 103); Grapes grapes = new Grapes(); addObject(grapes, 506, 235); } }

I don't see the act method in the code you posted, so add this:

I tried and it said that line 1. was an illegal expression so I deleted it and it had no errors but when I die I still don't respawn. Here is my class again: import greenfoot.*; /** * Class MyWorld: sample world to show how to make use of my world super-class SWorld */ public class MyWorld extends SWorld { /** * Creates a scrolling world using a main actor, a background, some obstacles, and a non-scrolling score. */ public MyWorld() { super(900, 400, 1, 1000); // scroll world constructor call; last parameter is scroll width // in the following statement, the main actor is placed in the center of the window setMainActor(new Lobster(), 250, 300); // the int parameters are centered window x and y ranges // to start the main actor elsewhere mainActor.setLocation(100, 342); { if (getObjects(Lobster.class).size() == 0) { addObject(new Lobster(),100,342); } } This time I left out all of the dot thingys

Go to your SWorld class (NOT MyWorld), and look for this: Make it look just like this:

I did that but a new error occurs: private void scrollBackground() it says this(above) has a class, interface, or enum expected Why?