android - Android 5 onInterceptTouchEvent モジュールの SwipeRefreshLayout.java に中断はありません

Question

その関数では、Action_down の後にブレークがなく、コードが ACTION_MOVE に実行される可能性があることに気付きました。そうですか?

@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
    ensureTarget();

    final int action = MotionEventCompat.getActionMasked(ev);

    if (mReturningToStart && action == MotionEvent.ACTION_DOWN) {
        mReturningToStart = false;
    }

    if (!isEnabled() || mReturningToStart || canChildScrollUp() || mRefreshing) {
        // Fail fast if we're not in a state where a swipe is possible
        return false;
    }

    switch (action) {
        case MotionEvent.ACTION_DOWN:
            setTargetOffsetTopAndBottom(mOriginalOffsetTop - mCircleView.getTop(), true);
            mActivePointerId = MotionEventCompat.getPointerId(ev, 0);
            mIsBeingDragged = false;
            final float initialMotionY = getMotionEventY(ev, mActivePointerId);
            if (initialMotionY == -1) {
                return false;
            }
            mInitialMotionY = initialMotionY;
           //-------NO Break here, why? It will run down to ACTION_MOVE
        case MotionEvent.ACTION_MOVE:
            if (mActivePointerId == INVALID_POINTER) {
                Log.e(LOG_TAG, "Got ACTION_MOVE event but don't have an active pointer id.");
                return false;
            }
            final float y = getMotionEventY(ev, mActivePointerId);
            if (y == -1) {
                return false;
            }
            final float yDiff = y - mInitialMotionY;
            if (yDiff > mTouchSlop && !mIsBeingDragged) {
                mIsBeingDragged = true;
                mProgress.setAlpha(STARTING_PROGRESS_ALPHA);
            }
            break;

        case MotionEventCompat.ACTION_POINTER_UP:
            onSecondaryPointerUp(ev);
            break;

        case MotionEvent.ACTION_UP:
        case MotionEvent.ACTION_CANCEL:
            mIsBeingDragged = false;
            mActivePointerId = INVALID_POINTER;
            break;
    }

    return mIsBeingDragged;
}

ACTION_DOWN を処理してから直接 ACTION_MOVE を処理する理由がわかりません。これでよろしいですか? 前もって感謝します。