1 files changed, 106 insertions, 0 deletions
diff --git a/darwin-bootstrap/safety-dance/AutoGrid.m b/darwin-bootstrap/safety-dance/AutoGrid.m
new file mode 100644
index 0000000..2a8d3ed
--- /dev/null
+++ b/darwin-bootstrap/safety-dance/AutoGrid.m
@@ -0,0 +1,106 @@
+//
+//  AutoGrid.m
+//  SafetyDance
+//
+//  Created by Nicholas Allegra on 1/26/15.
+//  Copyright (c) 2015 Nicholas Allegra. All rights reserved.
+//
+
+#import "AutoGrid.h"
+
+@implementation AutoGrid
+- (void)setViews:(NSArray *)_views {
+    views = _views;
+    [scrollView removeFromSuperview];
+    scrollView = [[UIScrollView alloc] init];
+    [self addSubview:scrollView];
+    for (UIView *view in views)
+        [scrollView addSubview:view];
+    [self setNeedsLayout];
+}
+
+- (void)layoutSubviews {
+    scrollView.frame = self.bounds;
+    CGFloat paddingX = 22, paddingY = 10;
+    NSUInteger nviews = [views count];
+    CGSize *sizes = malloc(sizeof(*sizes) * nviews);
+
+    for (NSUInteger i = 0; i < nviews; i++)
+        sizes[i] = [[views objectAtIndex:i] intrinsicContentSize];
+
+    CGFloat availableWidth = self.bounds.size.width;
+    /* try to lay out using an increasing number of columns */
+    NSUInteger cols;
+    CGSize contentSize;
+    CGFloat *colWidths = NULL;
+    for (cols = 1; ; cols++) {
+        free(colWidths);
+        colWidths = malloc(sizeof(*colWidths) * cols);
+        for (NSUInteger col = 0; col < cols; col++)
+            colWidths[col] = 0;
+        CGFloat tentativeHeight = 0;
+        CGFloat tentativeWidth = 0;
+        for (NSUInteger row = 0; row < nviews / cols; row++) {
+            CGFloat totalWidth = 0;
+            CGFloat maxHeight = 0;
+            for (NSUInteger col = 0; col < cols; col++) {
+                NSUInteger i = row * cols + col;
+                if (i >= nviews)
+                    goto done1;
+                CGSize size = sizes[i];
+                if (size.width > colWidths[col])
+                    colWidths[col] = size.width;
+                if (col != 0)
+                    totalWidth += paddingX;
+                totalWidth += size.width;
+                if (size.height > maxHeight)
+                    maxHeight = size.height;
+            }
+            if (totalWidth > tentativeWidth)
+                tentativeWidth = totalWidth;
+            tentativeHeight += maxHeight + paddingY;
+        }
+    done1:
+        if (cols > 1 && tentativeWidth > availableWidth) {
+            cols--;
+            break;
+        }
+        contentSize = CGSizeMake(tentativeWidth, tentativeHeight);
+        NSLog(@"%f", contentSize.height);
+        if (contentSize.width == 0)
+            break;
+
+    }
+    scrollView.contentSize = contentSize;
+    CGFloat y = 0;
+    for (NSUInteger row = 0; ; row++) {
+        CGFloat x = 0;
+        CGFloat maxHeight = 0;
+        for (NSUInteger col = 0; col < cols; col++) {
+            NSUInteger i = row * cols + col;
+            if (i >= nviews)
+                goto done2;
+            CGSize size = sizes[i];
+            UIView *view = [views objectAtIndex:i];
+            if (col != 0)
+                x += paddingX;
+            view.frame = CGRectMake(x, y, size.width, size.height);
+            x += colWidths[col];
+            if (size.height > maxHeight)
+                maxHeight = size.height;
+        }
+        y += maxHeight + paddingY;
+    }
+done2:
+    free(sizes);
+    free(colWidths);
+}
+/*
+// Only override drawRect: if you perform custom drawing.
+// An empty implementation adversely affects performance during animation.
+- (void)drawRect:(CGRect)rect {
+    // Drawing code
+}
+*/
+
+@end