Merge branch 'label'

Author: xhacker

TEAChart/TEABarChart.h

@@ -13,6 +13,9 @@
 // Array of NSNumber
 @property (nonatomic) NSArray *data;
 
+// Array of NSString, nil if you don't want labels.
+@property (nonatomic) NSArray *xLabels;
+
 // Max y value for chart (only works when autoMax is NO)
 @property (nonatomic) CGFloat max;
 

TEAChart/TEABarChart.m

@@ -31,7 +31,9 @@ - (id)initWithCoder:(NSCoder *)decoder
 - (void)loadDefaults
 {
     self.opaque = NO;
-    
+
+    _xLabels = nil;
+
     _autoMax = YES;
 
     _barColor = [UIColor colorWithRed:106.0/255 green:175.0/255 blue:232.0/255 alpha:1];
@@ -51,10 +53,28 @@ - (void)drawRect:(CGRect)rect
     NSInteger numberOfBars = self.data.count;
     CGFloat barWidth = (CGRectGetWidth(rect) - self.barSpacing * (numberOfBars - 1)) / numberOfBars;
     CGFloat barWidthRounded = ceil(barWidth);
-    
+
+    if (self.xLabels) {
+        CGFloat fontSize = floor(barWidth);
+        CGFloat labelsTopMargin = ceil(fontSize * 0.33);
+        barMaxHeight -= (fontSize + labelsTopMargin);
+
+        [self.xLabels enumerateObjectsUsingBlock:^(NSString *label, NSUInteger idx, BOOL *stop) {
+            NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc]init] ;
+            paragraphStyle.alignment = NSTextAlignmentCenter;
+
+            [label drawInRect:CGRectMake(idx * (barWidth + self.barSpacing), barMaxHeight + labelsTopMargin, barWidth, barWidth)
+               withAttributes:@{
+                                NSFontAttributeName:[UIFont fontWithName:@"HelveticaNeue" size:fontSize],
+                                NSForegroundColorAttributeName:[UIColor colorWithWhite:0.56 alpha:1],
+                                NSParagraphStyleAttributeName:paragraphStyle,
+                                }];
+        }];
+    }
+
     for (NSInteger i = 0; i < numberOfBars; i += 1)
     {
-        CGFloat barHeight = barMaxHeight * [self.data[i] floatValue] / max;
+        CGFloat barHeight = (max == 0 ? 0 : barMaxHeight * [self.data[i] floatValue] / max);
         if (barHeight > barMaxHeight) {
             barHeight = barMaxHeight;
         }
@@ -83,6 +103,12 @@ - (void)setData:(NSArray *)data
     [self setNeedsDisplay];
 }
 
+- (void)setXLabels:(NSArray *)xLabels
+{
+    _xLabels = xLabels;
+    [self setNeedsDisplay];
+}
+
 - (void)setMax:(CGFloat)max
 {
     _max = max;

TEAChartDemo/TEAViewController.m

@@ -22,14 +22,15 @@ - (void)viewDidLoad
 {
     [super viewDidLoad];
 
-    // Line chart, the Storyboard way
+    // Bar chart, the Storyboard way
     self.barChart.data = @[@3, @1, @4, @1, @5, @9, @2, @6, @5, @3];
     self.barChart.barSpacing = 10;
     self.barChart.barColors = @[[UIColor orangeColor], [UIColor yellowColor], [UIColor greenColor], [UIColor blueColor]];
 
-    // Line chart, the code way
-    TEABarChart *secondBarChart = [[TEABarChart alloc] initWithFrame:CGRectMake(35, 180, 100, 40)];
+    // Bar chart, the code way
+    TEABarChart *secondBarChart = [[TEABarChart alloc] initWithFrame:CGRectMake(35, 180, 100, 56)];
     secondBarChart.data = @[@2, @7, @1, @8, @2, @8];
+    secondBarChart.xLabels = @[@"A", @"B", @"C", @"D", @"E", @"F"];
     [self.view addSubview:secondBarChart];
 
     // Contribution graph