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2018年05月12日 ⁄ 综合 ⁄ 共 16674字 ⁄ 字号小中大 ⁄ 评论关闭

学习了网上的一些CoreText知识之后，总结了一下学习成果，自定义了一个Label控件。

Label特点：

1、可以设置文本中某些字段为关键字；

2、可以设置文本颜色和其中关键字的颜色；

3、可以设置文本下划线样式和其中关键字下划线样式；

4、可以指定文本字体与大小和其中关键字的字体与大小；

5、可以响应关键字点击；

说明一下其中的关键类的意义：

CHLabel.h 自定义的控件，继承自UILabel；

TestViewController.h 是项目的根视图控制器，其中使用了CHLabel；

下面看代码：

CHLabel 代码实现：

[cpp]
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#import <UIKit/UIKit.h>
#import<CoreText/CoreText.h>
typedef enum
{
kCHLabelUnderlineStyleNone = 0 ,
kCHLabelUnderlineStyleSingle ,
kCHLabelUnderlineStyleThick ,
kCHLabelUnderlineStyleDouble
} CHLabelUnderlineStyle;
@protocol CHLabelDelegate;
@interface CHLabel : UILabel
{
NSString *_textCH; //文本
UIColor *_textColorCH; //文本颜色
UIFont *_textFontCH; //文本字体
CHLabelUnderlineStyle _textUnderlineStyle; //文本下划线
NSString *_textKeyWordCH; //关键字
UIColor *_textKeyWordColorCH; //关键字颜色
UIFont *_keyWordFontCH; //关键字字体
CHLabelUnderlineStyle _keyWordUnderlineStyle;//关键字下划线
NSMutableArray *_keyWordsCH; //关键字数组
NSMutableAttributedString *_attributedString; //属性字符串
}
@property (nonatomic, copy) NSString *textCH;
@property (nonatomic, retain) UIColor *textColorCH;
@property (nonatomic, copy) NSString *textKeyWordCH;
@property (nonatomic, retain) UIColor *textKeyWordColorCH;
@property (nonatomic, retain) UIFont *textFontCH;
@property (nonatomic, retain) UIFont *keyWordFontCH;
@property (nonatomic, retain) NSMutableArray *keyWordsCH;
@property (nonatomic, retain) NSMutableAttributedString *attributedString;
@property (nonatomic, retain) id<CHLabelDelegate> delegate;
- (void) setText:(NSString *) textString andKeyWord:(NSString *) keyWord;
- (void) setTextColor:(UIColor *)textColor andKeyWordColor:(UIColor *) keyWordColor;
- (void) setTextFont: (UIFont *)textFont andKeyWordFont:(UIFont *) keyWordFont;
- (void) setTextUnderlineStyle: (CHLabelUnderlineStyle)textUnderlineStyle andKeyWordUnderlineStyle:(CHLabelUnderlineStyle) keyWordUnderlineStyle;
@end
@protocol CHLabelDelegate <NSObject>
@optional
- (void) CHLabel:(CHLabel *) chLabel tapOnKeyWord:(NSString *) keyWord;
@end
#import "CHLabel.h"
@implementation CHLabel
@synthesize textCH = _textCH;
@synthesize textColorCH = _textColorCH;
@synthesize textKeyWordCH = _textKeyWordCH;
@synthesize textKeyWordColorCH = _textKeyWordColorCH;
@synthesize textFontCH = _textFontCH;
@synthesize keyWordFontCH = _keyWordFontCH;
@synthesize keyWordsCH = _keyWordsCH;
@synthesize attributedString = _attributedString;
@synthesize delegate;
void safeRelease(id pointer)
{
if (!pointer)
{
[pointer release];
pointer = nil;
}
}
- (void) dealloc
{
safeRelease(_textCH);
safeRelease(_textColorCH);
safeRelease(_textKeyWordCH);
safeRelease(_textKeyWordColorCH);
safeRelease(_textFontCH);
safeRelease(_keyWordFontCH);
safeRelease(_keyWordsCH);
safeRelease(_attributedString);
safeRelease(delegate);
[super dealloc];
}
- (void) initializtion
{
_textKeyWordCH = nil;
_textKeyWordColorCH = nil;
_keyWordsCH = [[NSMutableArray alloc] init];
}
- (id) init
{
if (self = [super init])
{
[self initializtion];
}
return self;
}
- (id)initWithFrame:(CGRect)frame
{
if ([super initWithFrame:frame])
{
[self initializtion];
}
return self;
}
- (void) setText:(NSString *) textString andKeyWord:(NSString *) keyWord
{
if (self.text != textString)
{
self.text = textString;
self.textCH = textString;
}
[self fetchKeywordRange:keyWord];
}
- (void) setTextColor:(UIColor *)textColor andKeyWordColor:(UIColor *) keyWordColor
{
self.textColorCH = textColor;
self.textKeyWordColorCH = keyWordColor;
}
- (void) setTextFont:(UIFont *)textFont andKeyWordFont:(UIFont *) keyWordFont
{
self.textFontCH = textFont;
self.keyWordFontCH = keyWordFont;
}
- (void) setTextUnderlineStyle: (CHLabelUnderlineStyle)textUnderlineStyle andKeyWordUnderlineStyle:(CHLabelUnderlineStyle) keyWordUnderlineStyle
{
_textUnderlineStyle = textUnderlineStyle;
_keyWordUnderlineStyle = keyWordUnderlineStyle;
}
- (void) fetchKeywordRange:(NSString *)keyWord
{
if (nil == keyWord) {
return;
}
NSMutableAttributedString *mutableAttributedString = [[NSMutableAttributedString alloc] initWithString:self.text];
NSUInteger count = 0, length = [mutableAttributedString length];
NSRange range = NSMakeRange(0, length);
count = 0, length = [mutableAttributedString length];
range = NSMakeRange(0, length);
while(range.location != NSNotFound)
{
range = [[mutableAttributedString string] rangeOfString:keyWord options:0 range:range];
if(range.location != NSNotFound) {
NSValue *value = [NSValue valueWithRange:range];
if (range.length > 0) {
[self.keyWordsCH addObject:value];
}
range = NSMakeRange(range.location + range.length, length - (range.location + range.length));
count++;
}
}
}
- (int) labelUnderlineType:(CHLabelUnderlineStyle) lType
{
int underLineType;
switch (lType) {
case 0:
underLineType = kCTUnderlineStyleNone;
break;
case 1:
underLineType = kCTUnderlineStyleSingle;
break;
case 2:
underLineType = kCTUnderlineStyleThick;
break;
case 3:
underLineType = kCTUnderlineStyleDouble;
break;
default:
underLineType = kCTUnderlineStyleNone;
break;
}
return underLineType;
}
- (NSAttributedString *) richString:(NSString *) textString
{
int length = [textString length];
if (self.attributedString) {
self.attributedString = nil;
}
self.attributedString = [[NSMutableAttributedString alloc] initWithString:textString];
[self.attributedString addAttribute:(NSString *)(kCTForegroundColorAttributeName)
value:(id)self.textColorCH.CGColor
range:NSMakeRange(0, length)];
int numType = 0;
CFNumberRef cfNum = CFNumberCreate(NULL, kCFNumberIntType, &numType);
[self.attributedString addAttribute:(NSString *)kCTLigatureAttributeName
value:(id)cfNum
range:NSMakeRange(0, length)];
float fNum =3.0;
CFNumberRef cfNum2 = CFNumberCreate(NULL, kCFNumberFloatType, &fNum);
[self.attributedString addAttribute:(NSString *)(kCTStrokeColorAttributeName)
value:(id)cfNum2
range:NSMakeRange(0, length)];
if (!self.textFontCH) {
self.textFontCH = self.font;
}
CTFontRef ctFont = CTFontCreateWithName((CFStringRef)self.textFontCH.fontName, self.textFontCH.pointSize, NULL);
[self.attributedString addAttribute:(NSString *)(kCTFontAttributeName)
value:(id)ctFont
range:NSMakeRange(0, length)];
int underLineType = [self labelUnderlineType:_textUnderlineStyle];
CFNumberRef cfUnderLine = CFNumberCreate(NULL, kCTUnderlineStyleThick, &underLineType);
[self.attributedString addAttribute:(NSString *)(kCTUnderlineStyleAttributeName)
value:(id)cfUnderLine
range:NSMakeRange(0, length)];
if (self.textKeyWordColorCH != nil)
{
for (NSValue *value in self.keyWordsCH)
{
NSRange keyRange = [value rangeValue];
[self.attributedString addAttribute:(NSString *)(kCTForegroundColorAttributeName)
value:(id)self.textKeyWordColorCH.CGColor
range:keyRange];
if (!self.keyWordFontCH) {
self.keyWordFontCH = self.font;
}
CTFontRef ctFont = CTFontCreateWithName((CFStringRef)self.keyWordFontCH.fontName, self.keyWordFontCH.pointSize, NULL);
[self.attributedString addAttribute:(NSString *)(kCTFontAttributeName)
value:(id)ctFont
range:keyRange];
int underLineType = [self labelUnderlineType:_keyWordUnderlineStyle];
CFNumberRef cfUnderLine = CFNumberCreate(NULL, kCTUnderlineStyleThick, &underLineType);
[self.attributedString addAttribute:(NSString *)(kCTUnderlineStyleAttributeName)
value:(id)cfUnderLine
range:keyRange];
[self.attributedString addAttribute:@"option" value:[[self.attributedString string] substringWithRange:keyRange] range:keyRange];//弹出alert时候需要
}
}
return [[self.attributedString copy] autorelease];
}
- (void) drawRect:(CGRect)rect
{
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSaveGState(context);
CGContextConcatCTM(context, CGAffineTransformScale(CGAffineTransformMakeTranslation(0, rect.size.height+6.5), 1.f, -1.f));
CGContextSetTextPosition(context, 0.0, 0.0);
CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString((CFAttributedStringRef) [self richString:self.text]);
// NSLog(@"AttributedString:%@", [self richString:self.text font:self.font]);
CGMutablePathRef leftColumnPath = CGPathCreateMutable();
CGPathAddRect(leftColumnPath, NULL, rect);
CTFrameRef leftFrame = CTFramesetterCreateFrame(framesetter, CFRangeMake(0, 0), leftColumnPath, NULL);
CTFrameDraw(leftFrame, context);
CGContextRestoreGState(context);
CGPathRelease(leftColumnPath);
CFRelease(framesetter);
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesEnded:touches withEvent:event];
CGPoint tapLocation = [[touches anyObject] locationInView:self];
int total_height = [self getAttributedStringHeightWithString:self.attributedString WidthValue:self.frame.size.width];//width为自身宽度
//判断点击是否超出范围
if (tapLocation.y >= total_height) {
return;
}
/** 1. Setup CTFramesetter **/
CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString((CFAttributedStringRef)self.attributedString);
/** 2. Create CTFrame **/
CGMutablePathRef path = CGPathCreateMutable();
CGPathAddRect(path, NULL, CGRectMake(0, 0, self.frame.size.width, 1000));//height越大越好，
CTFrameRef textFrameForKey = CTFramesetterCreateFrame(framesetter, CFRangeMake(0, 0), path, NULL);
//[self drawFrame:textFrameForKey inContext:nil forString:nil];
CFRelease (path);
CFRelease (framesetter);
//CTFrameGetLineOrigins
NSArray *linesArray = (NSArray *) CTFrameGetLines(textFrameForKey);
CGPoint origins[[linesArray count]];
CTFrameGetLineOrigins(textFrameForKey, CFRangeMake(0, 0), origins);
CFArrayRef lines = CTFrameGetLines(textFrameForKey);
CGFloat ascent;
CGFloat descent;
CGFloat leading;
CTLineRef line = (CTLineRef) [linesArray objectAtIndex:0];
CTLineGetTypographicBounds(line, &ascent, &descent, &leading);
//CFIndex linesCount = CFArrayGetCount(lines);
int line_y = 1000- (int)origins[0].y; //第一行line的原点y坐标
int line_height = line_y + (int)descent +1; //每行的高度
int current_line = tapLocation.y/line_height;
CFIndex curentIndex = CTLineGetStringIndexForPosition((CTLineRef)CFArrayGetValueAtIndex(lines, current_line),tapLocation);
//判断超出范围
if (curentIndex >[self.attributedString length]) {
return;
}
NSRange currentRange = NSMakeRange(0, [self.attributedString length]);
//curentIndex
NSDictionary *dic = [self.attributedString attributesAtIndex:curentIndex-1 effectiveRange:¤tRange];
id option = [dic valueForKey:@"option"];
if (option) {
if ([delegate respondsToSelector:@selector(CHLabel:tapOnKeyWord:)])
{
[delegate CHLabel:self tapOnKeyWord:(NSString *)[dic valueForKey:@"option"]];
}
}
}
//获取coretext高度
- (int)getAttributedStringHeightWithString:(NSAttributedString *)string WidthValue:(int) width
{
int total_height = 0;
//string 为要计算高度的NSAttributedString
CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString((CFAttributedStringRef)string);
CGRect drawingRect = CGRectMake(0, 0, width, 1000); //这里的高要设置足够大
CGMutablePathRef path = CGPathCreateMutable();
CGPathAddRect(path, NULL, drawingRect);
CTFrameRef textFrame = CTFramesetterCreateFrame(framesetter,CFRangeMake(0,0), path, NULL);
CGPathRelease(path);
CFRelease(framesetter);
NSArray *linesArray = (NSArray *) CTFrameGetLines(textFrame);
CGPoint origins[[linesArray count]];
CTFrameGetLineOrigins(textFrame, CFRangeMake(0, 0), origins);
int line_y = (int) origins[[linesArray count] -1].y; //最后一行line的原点y坐标
CGFloat ascent;
CGFloat descent;
CGFloat leading;
CTLineRef line = (CTLineRef) [linesArray objectAtIndex:[linesArray count]-1];
CTLineGetTypographicBounds(line, &ascent, &descent, &leading);
total_height = 1000 - line_y + (int) descent +1; //+1为了纠正descent转换成int小数点后舍去的值
CFRelease(textFrame);
return total_height;
}
@end
TestViewController.h 代码实现：
@interface TestViewController : UIViewController <CHLabelDelegate>
{
IBOutlet UITextField *textString;
IBOutlet UITextField *keyString;
}
- (IBAction) showText:(id)sender;
@end
#import "TestViewController.h"
@interface TestViewController ()
@end
@implementation TestViewController
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (IBAction) showText:(id)sender
{
[textString resignFirstResponder];
[keyString resignFirstResponder];
CHLabel *label = [[CHLabel alloc] initWithFrame:CGRectMake(10, 260, 300, 200)];
[label setUserInteractionEnabled:YES];
[label setText:textString.text andKeyWord:keyString.text];
[label setTextColor:[UIColor redColor] andKeyWordColor:[UIColor blueColor]];
[label setTextUnderlineStyle:kCHLabelUnderlineStyleSingle andKeyWordUnderlineStyle:kCHLabelUnderlineStyleDouble];
[label setTextFont:[UIFont systemFontOfSize:20] andKeyWordFont:[UIFont boldSystemFontOfSize:30]];
label.backgroundColor = [UIColor lightGrayColor];
[label setNumberOfLines:0];
label.delegate = self;
NSArray *fontArray = [UIFont familyNames];
NSString *fontName;
if ([fontArray count]) {
fontName = [fontArray objectAtIndex:0];
}
[label setFont:[UIFont fontWithName:fontName size:20]];
[self.view addSubview:label];
// [label setNeedsDisplay];
[label release];
}
- (void)viewDidLoad
{
[super viewDidLoad];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
}
#pragma mark CHLabelDelegate
- (void) CHLabel:(CHLabel *) chLabel tapOnKeyWord:(NSString *) keyWord
{
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"notice"
message:[NSString stringWithFormat:@"Tap on keyWord:%@", keyWord]
delegate:nil
cancelButtonTitle:@"OK"
otherButtonTitles:nil];
[alert show];
[alert release];