Android Back Button on CC2.2.2

Hi… new question :frowning:
how is the correct way to implement the back button event in cocos creator? now don’t works…
this is the code:

cc.systemEvent.on(cc.SystemEvent.EventType.KEY_UP, this.onKeyUp, this);

onKeyUp(event) {

    if (event.keyCode === cc.macro.KEY.back) {

        this.emit();
    }
    else if (event.keyCode === cc.macro.KEY.backspace) {

        this.emit();
    }
    else if (event.keyCode === cc.macro.KEY.escape) {

        this.emit();
    }        
}, 

on PC works fine… on android nothing :frowning:
what we wrong? may be missing something to init?

Many thanks for help,

Stefano

What is your version of CocosCreator?

Cocos Creator 2.2.2

I just ran a test using vivo x7plus and there were no problems.

do you have used my same code?

const {ccclass, property} = cc._decorator;

@ccclass
export default class Helloworld extends cc.Component {

    @property(cc.Label)
    label: cc.Label = null;

    @property
    text: string = 'hello';

    start () {
        // init logic
        this.label.string = this.text;
        cc.systemEvent.on(cc.SystemEvent.EventType.KEY_UP, this.onKeyUp, this);
    }

    onKeyUp (event) {
        switch (event.keyCode) {
            case cc.macro.KEY.back:
                this.label.string = "input back";
                break;
        }
    }
}

yes it is same :confused:
only one thing is different we use javascript and not typescript… :frowning:

we have resolved with this…

                SDKWrapper.getInstance().onBackPressed();

                AppActivity app = (AppActivity) SDKWrapper.getInstance().getContext();
                app.runOnGLThread(new Runnable() {
                    @Override
                    public void run() {
                        Cocos2dxJavascriptJavaBridge.evalString("cc.onBackPressed();");
                    }
                });

with a our function… :confused: strange…