游戏在第一次运行时一切正常，但是在输后重新loadScene。this.anim变成null，但是只是在点击jump有这个问题。
已经在 onLoad 定义 this.anim = this.getComponent(cc.Animation); 不知道问什么仍然报错。
报错
Uncaught TypeError: Cannot read property 'stop' of null
出现问题的代码
changeState(state) {
this.state = state;
this.anim.stop();
this.anim.play(state);
},
完整代码
cc.Class({
extends: cc.Component,
properties: {
maxY: 0, // 620
groundY: 0, // -352, this is the default position when sheep is running
gravity: 0, // 980
initJumpSpeed: 0, // 600
},
changeState(state) {
this.state = state;
this.anim.stop();
this.anim.play(state);
},
jump() {
this.changeState("Jump");
this.currentSpeed = this.initJumpSpeed;
},
run() { // animation callback method
this.changeState("Run");
},
stopRun() {
this.changeState("Dead");
cc.eventManager.pauseTarget(this.node);
},
landed() {
this.changeState("Landed");
},
onCollisionEnter(other, self) {
var group = cc.game.groupList[other.node.groupIndex];
if (group == 'pipe') {
Global.gameManager.gameOver();
} else if (group = 'score') {
Global.gameManager.gainScore();
}
},
onLoad() {
Global.sheep = this;
this.currentSpeed = 0;
this.anim = this.getComponent(cc.Animation);
},
startRun () {
this.changeState('Run');
cc.eventManager.addListener({
event: cc.EventListener.TOUCH_ONE_BY_ONE,
onTouchBegan: function(touch, event) {
this.jump();
return true;
}.bind(this)
}, this.node);
},
update (dt) {
switch (this.state) {
case 'Jump':
if (this.currentSpeed < 0) {
this.changeState('Drop');
}
break;
case 'Drop':
if (this.node.y < this.groundY) {
this.node.y = this.groundY;
// this.changeState('Run');
this.landed();
}
break;
case 'Dead':
return;
}
if (this.node.y > this.maxY) { // when the sheep reach the top of the screen the fallback
this.node.y = this.maxY;
this.changeState('Drop');
}
var flying = this.state === 'Jump' || this.node.y > this.groundY;
if (flying) {
this.currentSpeed -= dt * this.gravity;
this.node.y += dt * this.currentSpeed;
}
},
});