看着 iBooks 应用程序,我想知道它如何完成格式化文本(可能是一个非常简单的 txt 文件),以便它不可滚动,而是分为不同的页面。
我想实现同样的目标,但前提是可编辑的文本。
我需要从哪里开始? UITextView 滚动时不起作用。即使我将 pagingEnabled 属性设置为 YES,它也无法完成这项工作。
似乎我需要限制可以在某个页面上放置的文本量。有没有限制 UITextView 输入的功能?我需要限制行数(不是字符),因为它们将显示在整个 iPhone 屏幕上(我猜你可以容纳 20 行左右,具体取决于字体大小)。
任何帮助,将不胜感激!由于我是初学者,我特别欣赏使用类似方法的示例。
Thanks!
您需要的是一种自己的布局算法,该算法获取文本,测量其大小并剪切它,直到它适合单页文本视图。然后从文本的其余部分开始,对于下一个文本视图也是如此......之后(或在算法内部)您将所有生成的文本视图排列在滚动视图上(或在数组中,稍后您可以翻转)带有分页动画 - 如果你喜欢它俗气的话)。我做了类似的事情,但是对于 UILabels,它也应该适用于文本视图。你需要的是:NSString's - (CGSize)sizeWithFont:(UIFont *)font constrainedToSize:(CGSize)size
and rangeOfString:@" " options:NSBackwardsSearch
(寻找单词空间)和substringFromIndex:
resp. substringToIndex:
如果您需要更多信息,请发表评论。
EDIT:
您好,以下代码未经测试,但包含您需要的大部分内容(希望如此),但可能存在一些错误,特别是在递归方面......我纠正了 BackWardsSearch 的想法,因为它可能需要很长时间才能削减很长的时间文本。我完全忽略了——这可能真的很棘手——是编辑时重新渲染。
但无论如何,这是代码。
这是一个假设为老 4 成员的视图控制器(头文件未发布):
UIView *editableBook;
NSMutableArray *content;
int currentPage;
UIFont *font;
这是控制器本身:
//
// EditableBookController.m
//
// Created by Kai on 09.03.11.
//
#import "EditableBookController.h"
@implementation EditableBookController
-(id)initWithText:(NSString *)text
{
if (self=[super init])
{
font = [UIFont fontWithName:@"SomeFont" size:12];
content = [[NSMutableArray alloc]init];
[self cutInPages:text];
currentPage = 0;
}
return self;
}
- (void)loadView
{
self.view = [[UIView alloc] initWithFrame:CGRectMake(.0, .0, 768., 1024.)];//assuming portrait only ...
editableBook = [[UIView alloc]initWithFrame:self.view.bounds];//could be a scroll view in alternate approach
UISwipeGestureRecognizer *flipper = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(nextOrPrevious:)];
[editableBook addGestureRecognizer:flipper];
[flipper release];
[self.view addSubview:editableBook];
UITextView *textView = [[UITextView alloc]initWithText:[content objectAtIndex:currentPage]];
textView.frame = editableBook.bounds;
textView.font = font;
textView.tag = 23;
[editableBook addSubview:textView];
[textView release];
}
-(void)nextOrPrevious:(id)sender
{
UISwipeGestureRecognizer *flipper = (UISwipeGestureRecognizer*)sender;
if(flipper.direction == UISwipeGestureRecognizerDirectionLeft)
{
[self next];
}
else if(flipper.direction == UISwipeGestureRecognizerDirectionRight)
{
[self previous];
}
}
-(void)next
{
if(currentPage == content.count - 1)
{
return;
}
currentPage++;
UIView *fromView = [editableBook viewWithTag:23];
UIView *toView = [[UITextView alloc]initWithText:[content objectAtIndex:currentPage]];
toView.frame = editableBook.bounds;
toView.tag = 23;
[UIView transitionWithView:editableBook duration:0.2 options:UIViewAnimationTransitionFlipFromRight
animations:^
{
[fromView removeFromSuperview];
[editableBook addSubview:toView];
}
completion:NULL];
}
-(void)previous
{
if(currentPage == 0)
{
return;
}
currentPage--;
UIView *fromView = [editableBook viewWithTag:23];
UIView *toView = [[UITextView alloc]initWithText:[content objectAtIndex:currentPage]];
toView.frame = editableBook.bounds;
toView.tag = 23;
[UIView transitionWithView:editableBook duration:0.2 options:UIViewAnimationTransitionFlipFromLeft
animations:^
{
[fromView removeFromSuperview];
[editableBook addSubview:toView];
}
completion:NULL];
}
-(void)cutInPages:(NSString *)text
{
NSRange whereToCut = whereToCut = [text rangeOfString:@" "];
NSString *pageText = [text substringToIndex:whereToCut.location];
NSString *rest = [text substringFromIndex:whereToCut.location];;
CGFloat height = 0;
while (height<1024.)
{
NSRange whereToCut = [rest rangeOfString:@" "];
NSString *wordOfRest = [rest substringToIndex:whereToCut.location];
pageText = [NSString stringWithFormat:@"%@%@", pageText, wordOfRest];
rest = [rest substringFromIndex:whereToCut.location];;
CGSize size = [pageText sizeWithFont:font
constrainedToSize:CGSizeMake(768., 10000)
lineBreakMode:UILineBreakModeWordWrap];
height = size.height;
}
if(height>1024.)
{
//TODO cut the last word of pageText and prepend to the eest
}
[content addObject:pageText];
if([rest length] > 0)
{
[self cutInPages:rest];
}
}
- (void)dealloc
{
[editableBook release];
[content release];
[super dealloc];
}
@end
本文内容由网友自发贡献,版权归原作者所有,本站不承担相应法律责任。如您发现有涉嫌抄袭侵权的内容,请联系:hwhale#tublm.com(使用前将#替换为@)