这个问题可能听起来很奇怪,但我已经挣扎了好几天了.
我有一个NSTextView,可以显示一些带有一些格式选项的文本.其中之一是能够为选择或当前行打开/关闭子弹列表(最简单的一个).
我知道在NSTextView上有一个orderFrontListPanel：方法打开窗口,其中包含可供选择和编辑的可用列表参数(例如,当您按Menu-> Format-> List …时在TextView中).
我已经想出并实现了手动添加项目符号,NSTextView似乎几乎正确地使用它们.通过说几乎我的意思是它保留标签位置,继续“输入”列表,等等.但是有一些小故障不适合我,不同于标准实施.
我试图找到以编程方式设置列表的默认方式,就像通过“列表…”菜单完成一样没有运气.
我请求帮助,每一点点的信息都会受到赞赏:).
P.S.：我已经查看了TextView源代码,发现了很多有趣但没有迹象或线索如何以编程方式启用列表.
更新
还在调查.我发现当你发送orderFrontListPanel：到你的NSTextView然后选择项目符号并按回车键时,没有特殊的消息被发送到NSTextView.这意味着可以在弹出式面板中的某处构建项目符号列表,并直接设置为TextView的文本容器…
解决方法
以编程方式将项目符号列表添加到NSTextView的两种方法：
方法1：
以下链接引导我使用第一种方法,但除非您想为子弹使用一些特殊的非Unicode字形,否则它将不必要地转向：
> Display hidden characters in NSTextView
> How to draw one NSGlyph,that hasn’t unicode representation?
> appendBezierPathWithGlyph fails in [NSBezierPath currentPoint]
这需要：(1)子类化布局管理器,用子弹字形替换某些任意字符; (2)带有firstLineHeadIndent的段落样式,比该缩进略大的制表位,以及用于组合两者的包裹线的headIndent.
布局管理器如下所示：
#import <Foundation/Foundation.h>
@interface TickerLayoutManager : NSLayoutManager {
// Might as well let this class hold all the fonts used by the progress ticker.
// That way they're all defined in one place,the init method.
NSFont *fontNormal;
NSFont *fontIndent; // smaller,for indented lines
NSFont *fontBold;
NSGlyph glyphBullet;
CGFloat fWidthGlyPHPlusSpace;
}
@property (nonatomic,retain) NSFont *fontNormal;
@property (nonatomic,retain) NSFont *fontIndent;
@property (nonatomic,retain) NSFont *fontBold;
@property NSGlyph glyphBullet;
@property CGFloat fWidthGlyPHPlusSpace;
@end
#import "TickerLayoutManager.h"
@implementation TickerLayoutManager
@synthesize fontNormal;
@synthesize fontIndent;
@synthesize fontBold;
@synthesize glyphBullet;
@synthesize fWidthGlyPHPlusSpace;
- (id)init {
self = [super init];
if (self) {
self.fontNormal = [NSFont fontWithName:@"Baskerville" size:14.0f];
self.fontIndent = [NSFont fontWithName:@"Baskerville" size:12.0f];
self.fontBold = [NSFont fontWithName:@"Baskerville Bold" size:14.0f];
// Get the bullet glyph.
self.glyphBullet = [self.fontIndent glyphWithName:@"bullet"];
// To determine its point size,put it in a Bezier path and take its bounds.
NSBezierPath *bezierPath = [NSBezierPath bezierPath];
[bezierPath moveToPoint:NSMakePoint(0.0f,0.0f)]; // prevents "No current point for line" exception
[bezierPath appendBezierPathWithGlyph:self.glyphBullet inFont:self.fontIndent];
NSRect rectGlyphOutline = [bezierPath bounds];
// The bullet should be followed with a space,so get the combined size...
NSSize sizeSpace = [@" " sizeWithAttributes:[NSDictionary dictionaryWithObject:self.fontIndent forKey:NSFontAttributeName]];
self.fWidthGlyPHPlusSpace = rectGlyphOutline.size.width + sizeSpace.width;
// ...which is for some reason inexact. If this number is too low,your bulleted text will be thrown to the line below,so add some boost.
self.fWidthGlyPHPlusSpace *= 1.5; //
}
return self;
}
- (void)drawGlyphsForGlyphRange:(NSRange)range
atPoint:(NSPoint)origin {
// The following prints only once,even though the textview's string is set 4 times,so this implementation is not too expensive.
printf("\nCalling TickerLayoutManager's drawGlyphs method.");
NSString *string = [[self textStorage] string];
for (int i = range.location; i < range.length; i++) {
// Replace all occurrences of the ">" char with the bullet glyph.
if ([string characterAtIndex:i] == '>')
[self replaceGlyphAtIndex:i withGlyph:self.glyphBullet];
}
[super drawGlyphsForGlyphRange:range atPoint:origin];
}
@end
将布局管理器分配给窗口/视图控制器的awakeFromNib中的textview,如下所示：
- (void) awakeFromNib {
// regular setup...
// Give the ticker display NSTextView its subclassed layout manager.
TickerLayoutManager *newLayoutMgr = [[TickerLayoutManager alloc] init];
NSTextContainer *textContainer = [self.txvProgressTicker textContainer];
// Use "replaceLM" rather than "setLM," in order to keep shared relnshps intact.
[textContainer replaceLayoutManager:newLayoutMgr];
[newLayoutMgr release];
// (Note: It is possible that all text-displaying controls in this class’s window will share this text container,as they would a field editor (a textview),although the fact that the ticker display is itself a textview might isolate it. Apple's "Text System Overview" is not clear on this point.)
}
- (void) addProgressTickerLine:(NSString *)string
inStyle:(uint8_t)uiStyle {
// Null check.
if (!string)
return;
// Prepare the font.
// (As noted above,TickerLayoutManager holds all 3 ticker display fonts.)
NSFont *font = nil;
TickerLayoutManager *tickerLayoutMgr = (TickerLayoutManager *)[self.txvProgressTicker layoutManager];
switch (uiStyle) {
case kTickerStyleNormal:
font = tickerLayoutMgr.fontNormal;
break;
case kTickerStyleIndent:
font = tickerLayoutMgr.fontIndent;
break;
case kTickerStyleBold:
font = tickerLayoutMgr.fontBold;
break;
default:
font = tickerLayoutMgr.fontNormal;
break;
}
// Prepare the paragraph style,to govern indentation.
// CAUTION: If you propertize it for re-use,make sure you don't mutate it once it has been assigned to an attributed string. (See warning in class ref.)
// At the same time,add the initial line break and,if indented,the tab.
NSMutableParagraphStyle *paragStyle = [[NSParagraphStyle defaultParagraphStyle] mutableCopy]; // ALLOC
[paragStyle setAlignment:NSLeftTextAlignment]; // default,but just in case
if (uiStyle == kTickerStyleIndent) {
// (The custom layout mgr will replace ‘>’ char with a bullet,so it should be followed with an extra space.)
string = [@"\n>\t" stringByAppendingString:string];
// Indent the first line up to where the bullet should appear.
[paragStyle setFirstLineHeadIndent:15.0f];
// Define a tab stop to the right of the bullet glyph.
NSTextTab *textTabFllwgBullet = [[NSTextTab alloc] initWithType:NSLeftTabStopType location:15.0f + tickerLayoutMgr.fWidthGlyPHPlusSpace];
[paragStyle setTabStops:[NSArray arrayWithObject:textTabFllwgBullet]];
[textTabFllwgBullet release];
// Set the indentation for the wrapped lines to the same place as the tab stop.
[paragStyle setHeadIndent:15.0f + tickerLayoutMgr.fWidthGlyPHPlusSpace];
}
else {
string = [@"\n" stringByAppendingString:string];
}
// PUT IT ALL TOGETHER.
// Combine the above into a dictionary of attributes.
NSDictionary *dict = [NSDictionary dictionaryWithObjectsAndKeys:
font,NSFontAttributeName,paragStyle,NSParagraphStyleAttributeName,nil];
// Use the attributes dictionary to make an attributed string out of the plain string.
NSAttributedString *attrs = [[NSAttributedString alloc] initWithString:string attributes:dict]; // ALLOC
// Append the attributed string to the ticker display.
[[self.txvProgressTicker textStorage] appendAttributedString:attrs];
// RELEASE
[attrs release];
[paragStyle release];
}
测试出来：
NSString *sTicker = NSLocalizedString(@"First normal line of ticker should wrap to left margin",@"First normal line of ticker should wrap to left margin"); [self addProgressTickerLine:sTicker inStyle:kTickerStyleNormal]; sTicker = NSLocalizedString(@"Indented ticker line should have bullet point and should wrap farther to right.",@"Indented ticker line should have bullet point and should wrap farther to right."); [self addProgressTickerLine:sTicker inStyle:kTickerStyleIndent]; sTicker = NSLocalizedString(@"Try a second indented line,to make sure both line up.",@"Try a second indented line,to make sure both line up."); [self addProgressTickerLine:sTicker inStyle:kTickerStyleIndent]; sTicker = NSLocalizedString(@"Final bold line",@"Final bold line"); [self addProgressTickerLine:sTicker inStyle:kTickerStyleBold];
你得到这个：
方法2：
但子弹是一个常规的Unicode字符,在十六进制2022.所以你可以直接把它放在字符串中,并得到一个精确的测量,如下所示：
NSString *stringWithGlyph = [NSString stringWithUTF8String:"\u2022"];
NSString *stringWithGlyPHPlusSpace = [stringWithGlyph stringByAppendingString:@" "];
NSSize sizeGlyPHPlusSpace = [stringWithGlyPHPlusSpace sizeWithAttributes:[NSDictionary dictionaryWithObject:self.fontIndent forKey:NSFontAttributeName]];
self.fWidthGlyPHPlusSpace = sizeGlyPHPlusSpace.width;
因此不需要自定义布局管理器.只需像上面一样设置paragStyle缩进,并将文本字符串附加到一个字符串,该字符串包含行返回项目符号空格(或选项卡,在这种情况下,您仍然希望该制表符停止).
使用空格,这产生了更严格的结果：
想要使用子弹以外的角色吗？这是一个很好的Unicode图表：http://www.danshort.com/unicode/
