入力の処理が終了したかどうか（読み取り専用）
Keyboard input process can be finished either by user tapping "Done"
button or script setting active property to false. Note that keyboard
might be temporarily inactive (either by sliding in/out due to
orientation change or by appearance of another keyboard), however its
input process might still be not finished and will be resumed
automatically.
// Opens a keyboard and shows what has been typed.
private var keyboard : TouchScreenKeyboard;
var text : String = "";
function Start() {
keyboard = TouchScreenKeyboard.Open(text, TouchScreenKeyboardType.Default);
}
function Update() {
if (keyboard != null && keyboard.done)
{
text = keyboard.text;
print ("User input is: " + text);
}
}