1 files changed, 145 insertions, 0 deletions
diff --git a/iPhone/GTMUIView+SubtreeDescription.m b/iPhone/GTMUIView+SubtreeDescription.m
new file mode 100644
index 0000000..bae0e2f
--- /dev/null
+++ b/iPhone/GTMUIView+SubtreeDescription.m
@@ -0,0 +1,145 @@
+//
+//  GTMUIView+SubtreeDescription.m
+//
+//  Copyright 2009 Google Inc.
+//
+//  Licensed under the Apache License, Version 2.0 (the "License"); you may not
+//  use this file except in compliance with the License.  You may obtain a copy
+//  of the License at
+//
+//  http://www.apache.org/licenses/LICENSE-2.0
+//
+//  Unless required by applicable law or agreed to in writing, software
+//  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+//  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+//  License for the specific language governing permissions and limitations
+//  under the License.
+//
+#import "GTMUIView+SubtreeDescription.h"
+
+#if DEBUG || INCLUDE_UIVIEW_SUBTREE_DESCRIPTION
+
+static void AppendLabelFloat(NSMutableString *s, NSString *label, float f) {
+  [s appendString:label];
+  // Respects gcc warning about using == with floats.
+  if (fabs(f - floor(f)) < 1.0e-8) { // Essentially integer.
+    int d = f;
+    // Respects gcc warning about casting floats to ints.
+    [s appendFormat:@"%d", d];
+  } else {
+    [s appendFormat:@"%3.1f", f];
+  }
+}
+
+
+static NSMutableString *SublayerDescriptionLine(CALayer *layer) {
+  NSMutableString *result = [NSMutableString string];
+  [result appendFormat:@"%@ %p {", [layer class], layer];
+  CGRect frame = [layer frame];
+  if (!CGRectIsEmpty(frame)) {
+    AppendLabelFloat(result, @"x:", frame.origin.x);
+    AppendLabelFloat(result, @" y:", frame.origin.y);
+    AppendLabelFloat(result, @" w:", frame.size.width);
+    AppendLabelFloat(result, @" h:", frame.size.height);
+  }
+  [result appendFormat:@"}"];
+  if ([layer isHidden]) {
+    [result appendString:@" hid"];
+  }
+  [result appendString:@"\n"];
+  return result;
+}
+
+// |sublayersDescription| has a guard so we'll only call this if it is safe
+// to call.
+static NSMutableString *SublayerDescriptionAtLevel(CALayer *layer, int level) {
+  NSMutableString *result = [NSMutableString string];
+  for (int i = 0; i < level; ++i) {
+    [result appendString:@"  "];
+  }
+  [result appendString:SublayerDescriptionLine(layer)];
+  // |sublayers| is defined in the QuartzCore framework, which isn't guaranteed
+  // to be linked to this program. (So we don't include the header.)
+  NSArray *layers = [layer performSelector:@selector(sublayers)];
+  for (CALayer *l in layers) {
+    [result appendString:SublayerDescriptionAtLevel(l, level+1)];
+  }
+  return result;
+}
+
+@implementation UIView (SubtreeDescription)
+
+// TODO: Consider flagging things which might help in debugging:
+// - alpha < 10%
+// - origin not zero
+// - non-opaque
+// - transform if not identity
+// - view not entirely within ancestor views
+// - (possibly) tag==0
+- (NSString *)gtm_subtreeDescriptionLine {
+  NSMutableString *result = [NSMutableString string];
+  [result appendFormat:@"%@ %p {", [self class], self];
+  CGRect frame = [self frame];
+  if (!CGRectIsEmpty(frame)) {
+    AppendLabelFloat(result, @"x:", frame.origin.x);
+    AppendLabelFloat(result, @" y:", frame.origin.y);
+    AppendLabelFloat(result, @" w:", frame.size.width);
+    AppendLabelFloat(result, @" h:", frame.size.height);
+  }
+  [result appendString:@"}"];
+  if ([self isHidden]) {
+    [result appendString:@" hid"];
+  }
+
+  if ([self respondsToSelector:@selector(myViewDescriptionLine)]) {
+    NSString *customDescription =
+      [self performSelector:@selector(myViewDescriptionLine)];
+    if (customDescription != nil) {
+      [result appendFormat:@" %@", customDescription];
+    }
+  }
+
+  [result appendString:@"\n"];
+  return result;
+}
+
+- (NSString *)gtm_subtreeDescriptionAtLevel:(int)level {
+  NSMutableString *result = [NSMutableString string];
+  for (int i = 0; i < level; ++i) {
+    [result appendString:@"  "];
+  }
+  [result appendString:[self gtm_subtreeDescriptionLine]];
+  for (UIView *v in [self subviews]) {
+    [result appendString:[v gtm_subtreeDescriptionAtLevel:level+1]];
+  }
+  return result;
+}
+
+- (NSString *)subtreeDescription {
+  NSMutableString *result =
+    [[[self gtm_subtreeDescriptionLine] mutableCopy] autorelease];
+  for (UIView *v in [self subviews]) {
+    [result appendString:[v gtm_subtreeDescriptionAtLevel:1]];
+  }
+  return result;
+}
+
+// for debugging dump the layer hierarchy, frames and isHidden.
+- (NSString *)sublayersDescription {
+  CALayer *layer = [self layer];
+  if (![layer respondsToSelector:@selector(sublayers)]) {
+    return @"*** Sorry: This app is not linked with the QuartzCore framework.";
+  }
+  NSMutableString *result = SublayerDescriptionLine(layer);
+  NSArray *layers = [layer performSelector:@selector(sublayers)];
+  for (CALayer *l in layers) {
+    [result appendString:SublayerDescriptionAtLevel(l, 1)];
+  }
+  return result;
+}
+
+@end
+
+#endif  // DEBUG
+
+