iOS学习4：UITextView的用法及技巧(ios7下光标bug解决方案)
一、新建一个textView
//初始化 UITextView *textView = [[[UITextView alloc] init] autorelease]; //设置代理 需在interface中声明UITextViewDelegate textView.delegate = self; //字体大小 textView.font = [UIFont systemFontOfSize:16]; //添加滚动区域 textView.contentInset = UIEdgeInsetsMake(-11, -6, 0, 0); //是否可以滚动 textView.scrollEnabled = NO; //获得焦点 [textView becomeFirstResponder];
[self.view addSubview:textView];
二、键盘操作
//返回键的类型 textView.returnKeyType = UIReturnKeyDefault; //键盘类型 textView.keyboardType = UIKeyboardTypeDefault;
三、隐藏键盘的几种方式
个人还是认为最方便的是在键盘上加上一个ToolBar，在上面加上一个按钮来隐藏键盘
①在键盘上加上隐藏按钮
//定义一个toolBar
UIToolbar * topView = [[UIToolbar alloc]initWithFrame:CGRectMake(0, 0, 320, 30)];
//设置style
[topView setBarStyle:UIBarStyleBlack];
//定义两个flexibleSpace的button，放在toolBar上，这样完成按钮就会在最右边
UIBarButtonItem * button1 =[[UIBarButtonItem alloc]initWithBarButtonSystemItem: UIBarButtonSystemItemFlexibleSpace target:self action:nil];
UIBarButtonItem * button2 = [[UIBarButtonItem alloc]initWithBarButtonSystemItem: UIBarButtonSystemItemFlexibleSpace target:self action:nil];
//定义完成按钮
UIBarButtonItem * doneButton = [[UIBarButtonItem alloc]initWithTitle:@"完成" style:UIBarButtonItemStyleDone target:self action:@selector(resignKeyboard)];
//在toolBar上加上这些按钮
NSArray * buttonsArray = [NSArray arrayWithObjects:button1,button2,doneButton,nil];
[topView setItems:buttonsArray];
[textView setInputAccessoryView:topView];
//隐藏键盘
- (void)resignKeyboard {
[textView resignFirstResponder];
} 最终效果
还有几种也可隐藏键盘的方式
②用回车键，前提是你的textView中不需要用到回车键
-(BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text {
if ([text isEqualToString:@"\n"])
{
[textView resignFirstResponder]; return NO;
}
return YES;
}
③触摸空白处隐藏键盘
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
//隐藏键盘
[textView resignFirstResponder];
}
四、使键盘不挡住输入框
在view中添加一个子view，设置此子view的tag值为1000，在此view上添加一个textView和一个发送按钮，如下图；我们要达到textView的键盘弹出时，整个View往上平移，键盘消失，view往下平移的效果，模拟发送短信的界面。
设置textView圆角
//设置textView圆角 [self.textView.layer setCornerRadius:10];
①、在viewWillAppear中添加键盘监听事件
//添加键盘的监听事件
//注册通知,监听键盘弹出事件
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardDidShow:) name:UIKeyboardDidShowNotification object:nil];
//注册通知,监听键盘消失事件
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardDidHidden) name:UIKeyboardDidHideNotification object:nil]; ②、完成①selector中键盘弹出keyboardDidShow:和消失keyboardDidHidden方法
在.m文件#import后面添加
//动画时间 #define kAnimationDuration 0.2 //view高度 #define kViewHeight 56键盘出现
// 键盘弹出时
-(void)keyboardDidShow:(NSNotification *)notification
{
//获取键盘高度
NSValue *keyboardObject = [[notification userInfo] objectForKey:UIKeyboardFrameEndUserInfoKey];
CGRect keyboardRect;
[keyboardObject getValue:&keyboardRect];
//调整放置有textView的view的位置
//设置动画
[UIView beginAnimations:nil context:nil];
//定义动画时间
[UIView setAnimationDuration:kAnimationDuration];
//设置view的frame，往上平移
[(UIView *)[self.view viewWithTag:1000] setFrame:CGRectMake(0, self.view.frame.size.height-keyboardRect.size.height-kViewHeight, 320, kViewHeight)];
[UIView commitAnimations];
}
键盘消失
//键盘消失时
-(void)keyboardDidHidden
{
//定义动画
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:kAnimationDuration];
//设置view的frame，往下平移
[(UIView *)[self.view viewWithTag:1000] setFrame:CGRectMake(0, self.view.frame.size.height-kViewHeight, 320, kViewHeight)];
[UIView commitAnimations];
}
效果图：
iOS7光标问题
PS：有网友遇到textView在ios7上出现编辑进入最后一行时光标消失，看不到最后一行，变成盲打，stackOverFlow网站上有大神指出，是ios7本身bug，加上下面一段代码即可（网友调试得出，在此mark一下，有问题，欢迎大神们指出）
-(void)textViewDidChange:(UITextView *)textView {
CGRect line = [textView caretRectForPosition:
textView.selectedTextRange.start];
CGFloat overflow = line.origin.y + line.size.height
- ( textView.contentOffset.y + textView.bounds.size.height
- textView.contentInset.bottom - textView.contentInset.top );
if ( overflow > 0 ) {
// We are at the bottom of the visible text and introduced a line feed, scroll down (iOS 7 does not do it)
// Scroll caret to visible area
CGPoint offset = textView.contentOffset;
offset.y += overflow + 7; // leave 7 pixels margin
// Cannot animate with setContentOffset:animated: or caret will not appear
[UIView animateWithDuration:.2 animations:^{
[textView setContentOffset:offset];
}];
}
}