public class UIHandler<T> extends Handler {
 
    protected WeakReference<T> ref;
 
    public UIHandler(T cls){
        ref = new WeakReference<T>(cls);
    }
 
    public T getRef(){
        return ref != null ? ref.get() : null;
    }

使用方法

private static class UIMyHandler extends UIHandler<HandlerActivity>{
 
        public UIMyHandler(HandlerActivity cls) {
            super(cls);
        }
 
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            HandlerActivity activity = ref.get();
            if (activity != null){
                if (activity.isFinishing())
                    return;
 
                switch (msg.what){
 
                    case 1:{
 
                        break;
                    }
 
                    // ...
 
                }
 
            }
        }
    }
 
    private UIMyHandler myHandler = new UIMyHandler(this);