编辑：我想我应该使用UILabel而不是UITextView,因为我不希望突出显示使用系统范围的蓝色和’copy / select all / define’popover.
我正在尝试构建自定义文本视图,我正在寻找正确方法的一些帮助.我是一个iOS n00b,所以主要是寻找有关如何最好地解决问题的想法.
我想构建一个自定义文本视图,具有以下行为：
>视图从小开始.如果它收到一个点击它会增长(动画)为父视图的大小作为模态窗口(左上图,然后右上图)
>在这个大状态中,如果单击一个单词,则单词以某种方式突出显示,并且委托方法称为传递包含被轻敲的字符串的字符串(左下图)
New Text View http://telliott.net/static/NewTextView.png
我怀疑复杂性将在于识别被点击的单词,所以让我们从那里开始.我可以想到几种尝试这种方法：
> UILabel子类.添加触摸手势识别器.识别触摸时,以某种方式获取触摸点的(x.y)坐标,查看视图显示的字符串,并根据位置确定必须按下哪个字.然而,我可以通过自动换行很快看到这变得非常复杂.我不确定如何获得触摸的(x,y)坐标(虽然我认为这很简单),或者如何获得每个角色等设备相关的文本宽度.我宁愿不去这条路线,除非有人可以说服我这不会太可怕！
> UIView子类,并通过为每个单词添加UILabel来伪造句子.测量每个UILabel的宽度并自己铺设.这似乎是一种更明智的方法,虽然我担心以这种方式布置文本也比我开始尝试时的想法更难.
有更明智的方法吗？你可以用其他方式检索UILabel中触及的单词吗？
如果我选择选项2,那么我认为动画来自小 – >大文本可能很复杂,因为单词将以有趣的方式包装.所以我想要另一个子视图 – 这次是UITextView – 将句子保持在小状态.将此动画设置为大,然后将其隐藏,同时以每个单词的一个视图显示我的UIView.
任何想法都赞赏.提前致谢 ：)
解决方法
更新
由于在CoreText中添加了NSLayoutManager,因此iOS 7更容易实现.如果您正在处理UITextView,则可以将布局管理器作为视图的属性进行访问.在我的情况下,我想坚持使用UILabel,所以你必须创建一个大小相同的布局管理器,即：
NSTextStorage *textStorage = [[NSTextStorage alloc] initWithAttributedString:labelText]; NSLayoutManager *layoutManager = [[NSLayoutManager alloc] init]; [textStorage addLayoutManager:layoutManager]; CGRect bounds = label.bounds; NSTextContainer *textContainer = [[NSTextContainer alloc] initWithSize:bounds.size]; [layoutManager addTextContainer:textContainer];
现在你只需要找到被点击的字符的索引,这很简单！
NSUInteger characterIndex = [layoutManager characterIndexForPoint:location
inTextContainer:textContainer
fractionOfDistanceBetweenInsertionPoints:NULL];
这使得找到这个词本身变得微不足道：
if (characterIndex < textStorage.length) {
[labelText.string enumerateSubstringsInRange:NSMakeRange(0,textStorage.length)
options:NSStringEnumerationByWords
usingBlock:^(NSString *substring,NSRange substringRange,NSRange enclosingRange,BOOL *stop) {
if (NSLocationInRange(characterIndex,enclosingRange)) {
// Do your thing with the word,at range 'enclosingRange'
*stop = YES;
}
}];
}
原始答案,适用于iOS< 7 感谢@JP Hribovsek提供了一些有关此工作的提示,我设法为我的目的解决了这个问题.它感觉有点hacky,对于大型文本可能不会很好,但对于一次一段(这是我需要的),它很好. 我创建了一个简单的UILabel子类,允许我设置插入值：
#import "WWLabel.h"
#define WWLabelDefaultInset 5
@implementation WWLabel
@synthesize topInset,leftInset,bottomInset,rightInset;
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
self.topInset = WWLabelDefaultInset;
self.bottomInset = WWLabelDefaultInset;
self.rightInset = WWLabelDefaultInset;
self.leftInset = WWLabelDefaultInset;
}
return self;
}
- (void)drawTextInRect:(CGRect)rect
{
UIEdgeInsets insets = {self.topInset,self.leftInset,self.bottomInset,self.rightInset};
return [super drawTextInRect:UIEdgeInsetsInsetRect(rect,insets)];
}
然后我创建了一个包含我的自定义标签的UIView子类,然后在标签上构建了标签中每个单词的文本大小,直到大小超过了点击位置的大小 – 这是被点击的单词.这不是完美的,但现在效果还不错.
然后我使用一个简单的NSAttributedString来突出显示文本：
#import "WWPhoneticTextView.h"
#import "WWLabel.h"
#define WWPhoneticTextViewInset 5
#define WWPhoneticTextViewDefaultColor [UIColor blackColor]
#define WWPhoneticTextViewHighlightColor [UIColor yellowColor]
#define UILabelMagicTopMargin 5
#define UILabelMagicLeftMargin -5
@implementation WWPhoneticTextView {
WWLabel *label;
NSMutableAttributedString *labelText;
NSRange tappedRange;
}
// ... skipped init methods,very simple,just call through to configureView
- (void)configureView
{
if(!label) {
tappedRange.location = NSNotFound;
tappedRange.length = 0;
label = [[WWLabel alloc] initWithFrame:[self bounds]];
[label setLineBreakMode:NSLineBreakByWordWrapping];
[label setNumberOfLines:0];
[label setBackgroundColor:[UIColor clearColor]];
[label setTopInset:WWPhoneticTextViewInset];
[label setLeftInset:WWPhoneticTextViewInset];
[label setBottomInset:WWPhoneticTextViewInset];
[label setRightInset:WWPhoneticTextViewInset];
[self addSubview:label];
}
// Setup tap handling
UITapGestureRecognizer *singleFingerTap = [[UITapGestureRecognizer alloc]
initWithTarget:self action:@selector(handleSingleTap:)];
singleFingerTap.numberOfTapsrequired = 1;
[self addGestureRecognizer:singleFingerTap];
}
- (void)setText:(NSString *)text
{
labelText = [[NSMutableAttributedString alloc] initWithString:text];
[label setAttributedText:labelText];
}
- (void)handleSingleTap:(UITapGestureRecognizer *)sender
{
if (sender.state == UIGestureRecognizerStateEnded)
{
// Get the location of the tap,and normalise for the text view (no margins)
CGPoint tapPoint = [sender locationInView:sender.view];
tapPoint.x = tapPoint.x - WWPhoneticTextViewInset - UILabelMagicLeftMargin;
tapPoint.y = tapPoint.y - WWPhoneticTextViewInset - UILabelMagicTopMargin;
// Iterate over each word,and check if the word contains the tap point in the correct line
__block NSString *partialString = @"";
__block NSString *lineString = @"";
__block int currentLineHeight = label.font.pointSize;
[label.text enumerateSubstringsInRange:NSMakeRange(0,[label.text length]) options:NSStringEnumerationByWords usingBlock:^(NSString* word,NSRange wordRange,BOOL* stop){
CGSize sizeForText = CGSizeMake(label.frame.size.width-2*WWPhoneticTextViewInset,label.frame.size.height-2*WWPhoneticTextViewInset);
partialString = [NSString stringWithFormat:@"%@ %@",partialString,word];
// Find the size of the partial string,and stop if we've hit the word
CGSize partialStringSize = [partialString sizeWithFont:label.font constrainedToSize:sizeForText lineBreakMode:label.lineBreakMode];
if (partialStringSize.height > currentLineHeight) {
// Text wrapped to new line
currentLineHeight = partialStringSize.height;
lineString = @"";
}
lineString = [NSString stringWithFormat:@"%@ %@",lineString,word];
CGSize lineStringSize = [lineString sizeWithFont:label.font constrainedToSize:label.frame.size lineBreakMode:label.lineBreakMode];
lineStringSize.width = lineStringSize.width + WWPhoneticTextViewInset;
if (tapPoint.x < lineStringSize.width && tapPoint.y > (partialStringSize.height-label.font.pointSize) && tapPoint.y < partialStringSize.height) {
NSLog(@"Tapped word %@",word);
if (tappedRange.location != NSNotFound) {
[labelText addAttribute:NSForegroundColorAttributeName value:[UIColor blackColor] range:tappedRange];
}
tappedRange = wordRange;
[labelText addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:tappedRange];
[label setAttributedText:labelText];
*stop = YES;
}
}];
}
}
