1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ 2 /* This Source Code Form is subject to the terms of the Mozilla Public 3 * License, v. 2.0. If a copy of the MPL was not distributed with this 4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ 5 6 #ifndef nsIPercentBSizeObserver_h___ 7 #define nsIPercentBSizeObserver_h___ 8 9 #include "nsQueryFrame.h" 10 11 namespace mozilla { 12 struct ReflowInput; 13 } // namespace mozilla 14 15 /** 16 * This interface is supported by frames that need to provide computed bsize 17 * values to children during reflow which would otherwise not happen. Currently 18 * only table cells support this. 19 */ 20 class nsIPercentBSizeObserver 21 { 22 public: 23 NS_DECL_QUERYFRAME_TARGET(nsIPercentBSizeObserver) 24 25 // Notify the observer that aReflowInput has no computed bsize, 26 // but it has a percent bsize 27 virtual void NotifyPercentBSize(const mozilla::ReflowInput& aReflowInput) = 0; 28 29 // Ask the observer if it should observe aReflowInput.frame 30 virtual bool NeedsToObserve(const mozilla::ReflowInput& aReflowInput) = 0; 31 }; 32 33 #endif // nsIPercentBSizeObserver_h___ 34