Unity3D KeyCode.Home问题？

Question

Hello i have a line of code that should quit the game upon pressing the three hardware button on the bottom like Menu, Home, Back it seems that the back and the home only is working but the menu is not working

I have a Xiaomi Redmi Note 4X phone, how am i suppose to fix this issue?

Is it the same "Menu" as the other phone where when you press it, it'll show list of the opened app

here's the code:

if (Input.GetKey (KeyCode.Home) || Input.GetKey (KeyCode.Escape) || Input.GetKey (KeyCode.Menu))
    {
        Save ();
        System.Diagnostics.Process.GetCurrentProcess ().Kill ();
    }

Answer 1

Is it the same "Menu" as the other phone where when you press it, it'll show list of the opened ap

Yes.

I have a Xiaomi Redmi Note 4X phone, how am i suppose to fix this issue?

It should work otherwise it is a bug and you should file for a bug request. Before you file for abug request, use the script below to make that the Menu key is not mapped to another key.

public class KeyCodeFinder : MonoBehaviour
{
    public Text text;

    Array allKeyCodes;

    void Start()
    {
        allKeyCodes = System.Enum.GetValues(typeof(KeyCode));
    }

    void Update()
    {
        foreach (KeyCode tempKey in allKeyCodes)
        {
            if (Input.GetKeyDown(tempKey))
            {
                text.text = "Pressed: KeyCode." + tempKey;
                Debug.Log("Pressed: KeyCode." + tempKey);
            }
        }
    }
}

---

Meanwhile, you can make a Java plugin that calls your C# function when the Menu keycode is pressed. That's another option you have.

Answer 2

Those buttons are OS related, you don't really control what happens with those. Well, you can track them and kill your app but this is going against what every single application does. That is, if you press the back or home or quit, it gets back to the main OS page, but your app is still on the stack ready to get back.

If you want to save when the user quits, maybe you want to look into

https://docs.unity3d.com/ScriptReference/MonoBehaviour.OnApplicationPause.html

This will make your app behave in a more common way.

On a side note, I would even assume this kind of attempt to over control the app would be rejected for AppStore (iOS) as it would not comply with their generic requirements.

Answer 3

It is allways possible to map a custom KeyCode that is not mapped so far.

First find out what keycode the key has

Event e = Event.current; 
if (e.isKey) 
{ 
    Debug.Log("Detected key code: " + e.keyCode); 
}

Let's say this gives you 10 as keycode (a one that is not mapped in Unities KeyCode so far)

You can than simply define a new one like

KeyCode MY_HOME_BUTTON = (KeyCode) 10;

and than use it like

if(Input.MY_HOME_BUTTON)
{
    ...
}

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If it is completely possible to catch the home button depends on the OS (most of the time those buttons cannot be catched by an app but are handled by the OS first)