Question

EDIT: This piece of code below is working. Unfortunately, i can’t test those key events in simulator so i made a mistake and sent the wrong apk to phone. Sorry about that.

I am trying this code that is given here: http://developer.coronalabs.com/reference/index/events/key/eventkeyname

However I can’t detect back key event. I tried to print event.keyName but it is not detecting it when i touched the back button on android device.

Can you please help me out? Thanks.

Here is my code:

  -- Key listener
    local function onKeyEvent( event )
        local phase = event.phase
        local keyName = event.keyName
        eventTxt.text = "("..phase.." , " .. keyName ..")"

        if(keyName=="back") then
        local a=display.newText("hello",100,600,nil,35)
        end
        -- we handled the event, so return true.
        -- for default behavior, return false.
        return true
     end

    -- Add the key callback
   Runtime:addEventListener( "key", onKeyEvent );

Answer 1

Production code of a game of mine:

function onBackButtonPressedAtMap(e)
    if (e.phase == "down" and e.keyName == "back") then
        --Here the key was pressed      
        downPress = true
        return true
    else 
        if (e.phase == "up" and e.keyName == "back" and downPress) then
            --Here the key was released, put your print("hello!") here.
            storyboard.gotoScene( "mapscreen", "fade", 200 );
            --The next line is to disable this event
            --so the key is not trapped anymore on the "mapscreen"
            --because I want the back key make the APP quit.
            Runtime:removeEventListener( "key", onBackButtonPressedAtMap );
            return true
        end
    end
    return false;
end