Add emoji scrollview

ISEmojiView/ISEmojiView.m

@@ -8,14 +8,77 @@
 
 #import "ISEmojiView.h"
 
-@implementation ISEmojiView
+static const CGFloat EmojiWidth = 50;
+static const CGFloat EmojiHeight = 50;
+static const CGFloat EmojiFontSize = 32;
 
-/*
-// Only override drawRect: if you perform custom drawing.
-// An empty implementation adversely affects performance during animation.
-- (void)drawRect:(CGRect)rect {
-    // Drawing code
-}
-*/
+@interface ISEmojiView()<UIScrollViewDelegate>
+
+@property (nonatomic, strong) NSArray *emojis;
+@property (nonatomic, strong) UIScrollView *scrollView;
+
+@end
+
+@implementation ISEmojiView
+
+-(instancetype)initWithFrame:(CGRect)frame{
+    self = [super initWithFrame:frame];
+    if (self) {
+        
+        // init emojis
+        NSString *plistPath = [[NSBundle mainBundle] pathForResource:@"ISEmojiList" ofType:@"plist"];
+        self.emojis = [NSArray arrayWithContentsOfFile:plistPath];
+        
+        //
+        NSInteger rowNum = (CGRectGetWidth(frame) / EmojiWidth);
+        NSInteger colNum = (CGRectGetHeight(frame) / EmojiHeight);
+        NSInteger numOfPage = ceil((float)[self.emojis count] / (float)(rowNum * colNum));
+        
+        // init scrollview
+        self.scrollView = [[UIScrollView alloc] initWithFrame:frame];
+        self.scrollView.pagingEnabled = YES;
+        self.scrollView.showsHorizontalScrollIndicator = NO;
+        self.scrollView.showsVerticalScrollIndicator = NO;
+        self.scrollView.delegate = self;
+        self.scrollView.contentSize = CGSizeMake(CGRectGetWidth(frame) * numOfPage,
+                                                 CGRectGetHeight(frame));
+        [self addSubview:self.scrollView];
+        
+        // add emojis
+        
+        NSInteger row = 0;
+        NSInteger column = 0;
+        NSInteger page = 0;
+        
+        for (int i = 0; i < [self.emojis count]; i++) {
+            
+            NSString *emoji = self.emojis[i];
+            
+            UIButton *emojiButton = [UIButton buttonWithType:UIButtonTypeCustom];
+            emojiButton.titleLabel.font = [UIFont fontWithName:@"Apple color emoji" size:EmojiFontSize];
+            [emojiButton setTitle:emoji forState:UIControlStateNormal];
+
+            // Pagination
+            if (i % (rowNum * colNum) == 0) {
+                page ++;    // Increase the number of pages
+                row = 0;    // the number of lines is 0
+                column = 0; // the number of columns is 0
+            }else if (i % rowNum == 0) {
+                // NewLine
+                row += 1;   // Increase the number of lines
+                column = 0; // The number of columns is 0
+            }
+            
+            emojiButton.frame = CGRectMake(((page-1) * frame.size.width) + (column * EmojiWidth),
+                                           row * EmojiHeight,
+                                           EmojiWidth,
+                                           EmojiHeight);
+            column++;
+            
+            [self.scrollView addSubview:emojiButton];
+        }
+    }
+    return self;
+}
 
 @end