是否可以为标签的某些部分设置背景颜色？我正在尝试创建类似于此帖子底部的标签部分的内容，在必要时，word包装和char包装。此外，文本块可以是多个单词。基本上我需要这样的东西：
[label setBackgroundColor:UIColor forRange:NSRange];
我需要支持iOS 5.0 +。
答案 0 :(得分：2)
我无法使用NSAttributedString使其工作。这是我的解决方案。它不是超级干净，但它可以正常工作。短语是一系列NSStrings。每个短语可以是单个单词或多个单词。
-(void)addBackgroundsToContainer:(UIView*)container color:(UIColor*)color phrases:(NSArray*)phrases {
CGFloat x = 0.0;
CGFloat y = 0.0;
UIView *lbl;
for(NSString *phrase in phrases) {
NSLog(@"Phrase: '%@'", phrase);
NSArray *words = [phrase componentsSeparatedByString:@" "];
NSString *text = @"";
for(int i = 0; i < words.count; i++) {
NSString *word = [words objectAtIndex:i];
CGSize wordSize = [word sizeWithFont:[self labelFont]];
CGSize textSize = [text sizeWithFont:[self labelFont]];
//if the word appended with the new text fits on one line, concatenate the two
if(textSize.width + wordSize.width + x < container.frame.size.width) {
text = [text isEqualToString:@""] ? word : [NSString stringWithFormat:@"%@ %@", text, word];
if(i == words.count -1 ) {//add the label if it's the last word
lbl = [self addLabelWithX:x y:y container:container color:color text:text];
x = lbl.frame.size.width + lbl.frame.origin.x + 1.0;
text = @"";
}
//if the word fits on one line but can't fit on the current line.
} else if(wordSize.width < container.frame.size.width) {
//if it's not the first word, add the text that came before it
if(i != 0) {
lbl = [self addLabelWithX:x width:container.frame.size.width - x y:y container:container color:color text:text];
}
x = 0.0;
y = lbl.frame.size.height + lbl.frame.origin.y + 1.0;
text = word;
//if it's the last word
if(i == words.count - 1) {
lbl = [self addLabelWithX:x y:y container:container color:color text:text];
x = lbl.frame.size.width + lbl.frame.origin.x + 1.0;
text = @"";
}
//if the word doesn't fit on one line and it
} else if(wordSize.width > container.frame.size.width) {
//I don't need to do char wrapping, but this would be where it'd go
}
}
}
}
-(UIView*)addLabelWithX:(CGFloat)x y:(CGFloat)y container:(UIView*)container color:(UIColor*)color text:(NSString*)text {
CGFloat width = [text sizeWithFont:[self labelFont]].width + 4.0;
return [self addLabelWithX:x width:width y:y container:container color:color text:text];
}
-(UIView*)addLabelWithX:(CGFloat)x width:(CGFloat)width y:(CGFloat)y container:(UIView*)container color:(UIColor*)color text:(NSString*)text {
CGFloat lineHeight = [@" " sizeWithFont:[self labelFont]].height;
UILabel *lbl = [[UILabel alloc] initWithFrame:CGRectMake(2.0, 0.0, width, lineHeight)];
[lbl setBackgroundColor:[UIColor clearColor]];
[lbl setTextColor:[UIColor whiteColor]];
[lbl setText:text];
[lbl setFont:[self labelFont]];
UIView *v = [[UIView alloc] initWithFrame:CGRectMake(x, y, width, lbl.frame.size.height)];
[v setBackgroundColor:color];
[v addSubview:lbl];
[container addSubview:v];
return v;
}
-(UIFont*)labelFont {
return [UIFont fontWithName:@"Lato-Regular" size:12.0];
}
#import <UIKit/UIKit.h>
@protocol WATagCloudDelegate;
@interface WATagCloud : UIView
@property(weak, nonatomic) id<WATagCloudDelegate> delegate;
@property(strong, nonatomic) NSArray *dataTags;
@property(strong, nonatomic) UIColor *tagColor;
@property(strong, nonatomic) UIFont *tagFont;
-(void)expand;
-(void)expandWithAnimation;
-(void)collapse;
-(void)collapseWithAnimation;
@end
@protocol WATagCloudDelegate <NSObject>
@required
-(void)tagCloudExpandDown:(WATagCloud*)tagCloud;
-(void)tagCloudCollapseDown:(WATagCloud*)tagCloud;
@end
的.m
#import "WATagCloud.h"
#import "WAControlsUtility.h"
@interface WATagCloud()
@property(strong, nonatomic) UIButton *btnToggleVisibility;
@property(strong, nonatomic) UIView *vExpand;
@property(strong, nonatomic) UILabel *lblExpand;
@end
@implementation WATagCloud
@synthesize dataTags = _dataTags;
@synthesize tagColor = _tagColor;
@synthesize tagFont = _tagFont;
@synthesize btnToggleVisibility;
@synthesize vExpand;
@synthesize lblExpand;
-(void)setTagColor:(UIColor *)color {
_tagColor = color;
[self setColorOfSubviews];
}
-(void)setDataTags:(NSArray *)tags {
_dataTags = tags;
[self addTags];
}
-(UIFont*)tagFont {
if(_tagFont) {
return _tagFont;
} else {
_tagFont = [UIFont fontWithName:@"Lato-Regular" size:14.0];
return _tagFont;
}
}
-(void)setTagFont:(UIFont *)font {
_tagFont = font;
[self addTags];
}
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
[self setClipsToBounds:YES];
self.btnToggleVisibility = [UIButton buttonWithType:UIButtonTypeCustom];
[self.btnToggleVisibility setFrame:CGRectMake(0.0, 0.0, self.frame.size.width, self.frame.size.height)];
[self.btnToggleVisibility addTarget:self action:@selector(onToggleVisibilityDown:) forControlEvents:UIControlEventTouchUpInside];
[self addSubview:self.btnToggleVisibility];
self.vExpand = [[UIView alloc] initWithFrame:CGRectMake(0.0, 0.0, 0.0, 0.0)];
[self addSubview:self.vExpand];
self.lblExpand = [[UILabel alloc] initWithFrame:CGRectMake(2.0, 0.0, 0.0, 0.0)];
[self.lblExpand setBackgroundColor:[UIColor clearColor]];
[self.lblExpand setTextColor:[UIColor whiteColor]];
[self.vExpand addSubview:self.lblExpand];
}
return self;
}
//======================================================================
//LAYOUT LABELS
//======================================================================
-(void)addTags {
[self clearTags];
CGFloat x = 0.0;
CGFloat y = 0.0;
UIView *lbl;
for(int j = 0; j < self.dataTags.count; j++) {
NSString *tag = [self.dataTags objectAtIndex:j];
NSArray *words = [tag componentsSeparatedByString:@" "];
NSString *text = @"";
for(int i = 0; i < words.count; i++) {
NSString *word = [words objectAtIndex:i];
CGSize wordSize = [word sizeWithFont:self.tagFont];
CGSize textSize = [text sizeWithFont:self.tagFont];
if(textSize.width + wordSize.width + x < self.frame.size.width) {//if the word appended with the new text fits on one line, concatenate the two
text = [text isEqualToString:@""] ? word : [NSString stringWithFormat:@"%@ %@", text, word];
if(i == words.count -1 ) {//add the label if it's the last word
lbl = [self addLabelWithX:x y:y text:text tag:j];
x = lbl.frame.size.width + lbl.frame.origin.x + 1.0;
text = @"";
}
} else if(wordSize.width < self.frame.size.width) {//if the word fits on one line but can't fit on the current line.
//if it's not the first word, add the text that came before it
if(i != 0) {
lbl = [self addLabelWithX:x width:self.frame.size.width - x y:y text:text tag:j];
}
x = 0.0;
y = lbl.frame.size.height + lbl.frame.origin.y + 1.0;
text = word;
//if it's the last word
if(i == words.count - 1) {
lbl = [self addLabelWithX:x y:y text:text tag:j];
x = lbl.frame.size.width + lbl.frame.origin.x + 1.0;
text = @"";
}
} else if(wordSize.width > self.frame.size.width) {//if the word doesn't fit on one line
NSArray *characters = [self getCharacterArrayFromString:word];
}
}
}
//update the frame height
[self setFrame:[WAControlsUtility updateFrame:self.frame withX:nil y:nil width:nil height:[NSNumber numberWithFloat:[WAControlsUtility getHeightOfView:self]]]];
[self.btnToggleVisibility setFrame:CGRectMake(0.0, 0.0, self.frame.size.width, self.frame.size.height)];
}
//======================================================================
//ADD TO CONTAINER
//======================================================================
-(UIView*)addLabelWithX:(CGFloat)x y:(CGFloat)y text:(NSString*)text tag:(int)tag {
CGFloat width = [text sizeWithFont:[self tagFont]].width + 4.0;
return [self addLabelWithX:x width:width y:y text:text tag:tag];
}
-(UIView*)addLabelWithX:(CGFloat)x width:(CGFloat)width y:(CGFloat)y text:(NSString*)text tag:(int)tag {
CGFloat lineHeight = [@" " sizeWithFont:[self tagFont]].height;
UILabel *lbl = [[UILabel alloc] initWithFrame:CGRectMake(2.0, 0.0, width, lineHeight)];
[lbl setBackgroundColor:[UIColor clearColor]];
[lbl setTextColor:[UIColor whiteColor]];
[lbl setText:text];
[lbl setFont:[self tagFont]];
UIView *v = [[UIView alloc] initWithFrame:CGRectMake(x, y, width, lbl.frame.size.height)];
[v setBackgroundColor:self.tagColor];
[v setTag:tag];
[v addSubview:lbl];
[self addSubview:v];
return v;
}
//======================================================================
//UI EVENTS
//======================================================================
-(void)onToggleVisibilityDown:(id)sender {
if(self.delegate ==nil)
return;
if(self.frame.size.height > [@" " sizeWithFont:[self tagFont]].height * 2.0 + 2) {//plus 2 for the spacing between lines
[self.delegate tagCloudCollapseDown:self];
} else {
[self.delegate tagCloudExpandDown:self];
}
}
//======================================================================
//PUBLIC METHODS
//======================================================================
//EXPAND
-(void)expand {
[self modifyViewsForExpanding];
[self setFrame:[WAControlsUtility updateFrame:self.frame withX:nil y:nil width:nil height:[NSNumber numberWithFloat:[WAControlsUtility getHeightOfView:self]]]];
[self.btnToggleVisibility setFrame:CGRectMake(0.0, 0.0, self.frame.size.width, self.frame.size.height)];
[self bringSubviewToFront:self.btnToggleVisibility];
}
-(void)expandWithAnimation {
[UIView animateWithDuration:.4 animations:^{
[self expand];
}];
}
//COLLAPSE
-(void)collapse {
CGFloat height = [@" " sizeWithFont:[self tagFont]].height * 2.0 + 2;//plus 2 for the spacing between lines
[self setFrame:[WAControlsUtility updateFrame:self.frame withX:nil y:nil width:nil height:[NSNumber numberWithFloat:height]]];
[self.btnToggleVisibility setFrame:CGRectMake(0.0, 0.0, self.frame.size.width, self.frame.size.height)];
[self modifyViewsForCollapsing];
[self bringSubviewToFront:self.btnToggleVisibility];
}
-(void)collapseWithAnimation {
[UIView animateWithDuration:.4 animations:^{
[self collapse];
}];
}
//======================================================================
//UTILITY
//======================================================================
-(NSArray*)getCharacterArrayFromString:(NSString*)string {
NSMutableArray *characters = [[NSMutableArray alloc] initWithCapacity:[string length]];
for (int i=0; i < [string length]; i++) {
NSString *ichar = [NSString stringWithFormat:@"%c", [string characterAtIndex:i]];
[characters addObject:ichar];
}
return characters;
}
-(void)setColorOfSubviews {
for(UIView *view in self.subviews) {
if([view isKindOfClass:[UIButton class]] == NO) {
if(view != self.vExpand) {
[view setBackgroundColor:self.tagColor];
} else {
[view setBackgroundColor:[self.tagColor colorWithAlphaComponent:.5]];
}
}
}
}
-(void)clearTags {
[self.subviews makeObjectsPerformSelector:@selector(removeFromSuperview)];
[self addSubview:self.btnToggleVisibility];
[self addSubview:self.vExpand];
}
//EXPAND/COLLAPSE UTILITY
-(NSArray*)getNthRow:(int)nth {//starts at 1 //not zero based
NSMutableArray *rowViews = [[NSMutableArray alloc] initWithCapacity:self.subviews.count];
CGFloat rowOrigin = [@" " sizeWithFont:self.tagFont].height * (nth - 1) + (nth - 1);
for(UIView *view in self.subviews) {
if([view isEqual:self.btnToggleVisibility] || [view isEqual:self.vExpand]) {//ignore the button and expand view
continue;
}
if(view.frame.origin.y == rowOrigin) {
[rowViews addObject:view];
}
}
return rowViews;
}
-(UIView*)getGreatestXOriginViewForNthRow:(int)nthRow {
NSArray *rowViews = [self getNthRow:nthRow];
UIView *greatestXOriginView = nil;
for(UIView *view in rowViews) {
if(greatestXOriginView == nil || view.frame.origin.x > greatestXOriginView.frame.origin.x ) {
greatestXOriginView = view;
}
}
return greatestXOriginView;
}
-(void)modifyViewsForCollapsing {
if([self getNthRow:3].count == 0) {
return;
}
UIView *greatestXOriginView = [self getGreatestXOriginViewForNthRow:2];
//update the label and the container
[self.lblExpand setText:[NSString stringWithFormat:@"+%d", self.dataTags.count - greatestXOriginView.tag]];
[self.lblExpand setFont:self.tagFont];
[self.lblExpand setFrame:[WAControlsUtility updateFrame:self.lblExpand.frame withX:nil y:nil width:[NSNumber numberWithFloat:[self.lblExpand.text sizeWithFont:self.tagFont].width] height:[NSNumber numberWithFloat:greatestXOriginView.frame.size.height]]];
[self resizeLabelContainer];
//figure out where to place the expand and how to size it and the last label on the row
CGFloat viewXValue = (greatestXOriginView.frame.size.width + greatestXOriginView.frame.origin.x);
CGFloat expandXValue = self.frame.size.width - self.vExpand.frame.size.width;
CGFloat xOrigin;
if(viewXValue < expandXValue - 1.0) {//will it all fit without modifying any existing views
xOrigin = viewXValue + 1.0;
} else {//shrink the last view
[greatestXOriginView setFrame:[WAControlsUtility updateFrame:greatestXOriginView.frame withX:nil y:nil width:[NSNumber numberWithFloat:expandXValue - 1 - greatestXOriginView.frame.origin.x] height:nil]];
for(UIView *view in greatestXOriginView.subviews) {//shrink the label
[view setFrame:[WAControlsUtility updateFrame:view.frame withX:nil y:nil width:[NSNumber numberWithFloat:greatestXOriginView.frame.size.width - 4.0] height:nil]];
}
if(greatestXOriginView.frame.size.width < 20.0) {
[greatestXOriginView setAlpha:0.0];//hide the last view if it got shrank down a lot
}
xOrigin = expandXValue;
}
[self.vExpand setFrame:[WAControlsUtility updateFrame:self.vExpand.frame withX:[NSNumber numberWithFloat:xOrigin] y:[NSNumber numberWithFloat:greatestXOriginView.frame.origin.y] width:nil height:nil]];
[self.vExpand setAlpha:1.0];
[self resizeLabelContainer];
}
-(void)modifyViewsForExpanding {
UIView *view = [self getGreatestXOriginViewForNthRow:2];
UILabel *label;
if(view != nil) {
label = (UILabel*)view.subviews[0];
CGSize labelSize = [label.text sizeWithFont:self.tagFont];
[label setFrame:[WAControlsUtility updateFrame:label.frame withX:nil y:nil width:[NSNumber numberWithFloat:labelSize.width] height:nil]];
[view setFrame:[WAControlsUtility updateFrame:view.frame withX:nil y:nil width:[NSNumber numberWithFloat:labelSize.width + 4] height:nil]];
[view setAlpha:1.0];
}
//hide expand
[self.vExpand setAlpha:0.0];
}
-(void)resizeLabelContainer {
[self.vExpand setFrame:[WAControlsUtility updateFrame:self.vExpand.frame withX:nil y:nil width:[NSNumber numberWithFloat:self.lblExpand.frame.size.width + 4.0] height:[NSNumber numberWithFloat:self.lblExpand.frame.size.height]]];
}
@end
答案 1 :(得分：1)
您可以尝试将NSAttributedString与NSBackgroundColorAttributeName属性一起使用。我没试过。