java - 从附加的OnPreDrawListener对象获取ViewTreeObserver对象

如何使观察者进入听众内部？
例：

ViewTreeObserver myObserver = myLayout.getViewTreeObserver();
myObserver.addOnPreDrawListener(new OnPreDrawListener() {
    @Override
    public boolean onPreDraw() {
        // I want to get the myLayout or myObserver here,
        // but I don't want to use the lines below
        RelativeLayout myLayout = (RelativeLayout)findViewById(myId);
        myLayout.getViewTreeObserver().removeOnPreDrawListener(this);

最佳答案

将其设为final或将其声明为实例变量，即在onCreate之前声明并初始化onCreate

final ViewTreeObserver myObserver = myLayout.getViewTreeObserver();

http://docs.oracle.com/javase/tutorial/java/javaOO/anonymousclasses.html#accessing

ViewTreeObserver.OnPreDrawListener是由匿名内部类实现的接口。因此要访问变量，必须为final。