1 // Copyright (c) 2011 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #import <Cocoa/Cocoa.h> 6 7 // BrowserFrameView is a class whose methods we swizzle into NSGrayFrame 8 // (an AppKit framework class) so that we can support custom frame drawing. 9 // This class is never to be instantiated on its own. 10 // We explored a variety of ways to support custom frame drawing and custom 11 // window widgets. 12 // Our requirements were: 13 // a) that we could fall back on standard system drawing at any time for the 14 // "default theme" 15 // b) We needed to be able to draw both a background pattern, and an overlay 16 // graphic, and we need to be able to set the pattern phase of our background 17 // window. 18 // c) We had to be able to support "transparent" themes, so that you could see 19 // through to the underlying windows in places without the system theme 20 // getting in the way. 21 // 22 // Since we want "A" we couldn't just do a transparent borderless window. At 23 // least I couldn't find the right combination of HITheme calls to make it draw 24 // nicely, and I don't trust that the HITheme calls are going to exist in future 25 // system versions. 26 // "C" precluded us from inserting a view between the system frame and the 27 // the content frame in Z order. To get the transparency we actually need to 28 // replace the drawing of the system frame. 29 // "B" precluded us from just setting a background color on the window. 30 // 31 // Originally we tried overriding the private API +frameViewForStyleMask: to 32 // add our own subclass of NSGrayView to our window. Turns out that if you 33 // subclass NSGrayView it does not draw correctly when you call NSGrayView's 34 // drawRect. It appears that NSGrayView's drawRect: method (and that of its 35 // superclasses) do lots of "isMemberOfClass/isKindOfClass" calls, and if your 36 // class is NOT an instance of NSGrayView (as opposed to a subclass of 37 // NSGrayView) then the system drawing will not work correctly. 38 // 39 // Given all of the above, we found swizzling drawRect in _load to be the 40 // easiest and safest method of achieving our goals. We do the best we can to 41 // check that everything is safe, and attempt to fallback gracefully if it is 42 // not. 43 @interface BrowserFrameView : NSView 44 45 // Draws the window theme into the specified rect. Returns whether a theme was 46 // drawn (whether incognito or full pattern theme; an overlay image doesn't 47 // count). 48 + (BOOL)drawWindowThemeInDirtyRect:(NSRect)dirtyRect 49 forView:(NSView*)view 50 bounds:(NSRect)bounds 51 offset:(NSPoint)offset 52 forceBlackBackground:(BOOL)forceBlackBackground; 53 54 // Gets the color to draw title text. 55 + (NSColor*)titleColorForThemeView:(NSView*)view; 56 57 @end 58
