UITextView及键盘隐藏

1.创建并初始化

UITextView

UITextView *textView;

self.textView = [[[UITextView alloc] initWithFrame:self.view.frame]autorelease]; //初始化大小并自动释放 self.textView.textColor = [UIColor blackColor];//设置textview里面的字体颜色 
self.textView.font = [UIFont fontWithName:@"Arial" size:18.0];//设置字体名字和字体大小 self.textView.delegate = self;//设置它的委托方法 
self.textView.backgroundColor = [UIColor whiteColor];//设置它的背景颜色
self.textView.text = @"Now is the time for all good developers tocome to serve their country.\n\nNow is the time for all good developers to cometo serve their country.";//设置它显示的内容 self.textView.returnKeyType = UIReturnKeyDefault;//返回键的类型 
self.textView.keyboardType = UIKeyboardTypeDefault;//键盘类型 
self.textView.scrollEnabled = YES;//是否可以拖动 
self.textView.autoresizingMask = UIViewAutoresizingFlexibleHeight;//自适应高度 
[self.view addSubview: self.textView];//加入到整个页面中

2.
UITextView退出键盘的几种方式

（1）如果你程序是有导航条的，可以在导航条上面加多一个Done的按钮，用来退出键盘，当然要先实UITextViewDelegate。

- (void)textViewDidBeginEditing:(UITextView *)textView {

            UIBarButtonItem *done = [[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(leaveEditMode)]
autorelease];                                

self.navigationItem.rightBarButtonItem = done;

}

- (void)textViewDidEndEditing:(UITextView *)textView {

self.navigationItem.rightBarButtonItem = nil;

}

- (void)leaveEditMode {

[self.textView resignFirstResponder];

}
（2）如果你的textview里不用回车键，可以把回车键当做退出键盘的响应键。

#pragma mark - UITextView Delegate Methods

-(BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text {
 if ([text isEqualToString:@"\n"]) 
{ 
[textView resignFirstResponder]; return NO; 
}
 return YES; 
}

这样无论你是使用电脑键盘上的回车键还是使用弹出键盘里的return键都可以达到退出键盘的效果。

（3）还有你也可以自定义其他加载键盘上面用来退出，比如在弹出的键盘上面加一个view来放置退出键盘的Done按钮。

UIToolbar * topView = [[UIToolbar alloc]initWithFrame:CGRectMake(0, 0, 320, 30)];
 [topView setBarStyle:UIBarStyleBlack]; 
UIBarButtonItem * helloButton = [[UIBarButtonItem alloc]initWithTitle:@"Hello" style:UIBarButtonItemStyleBordered target:self action:nil]; 
UIBarButtonItem * btnSpace = [[UIBarButtonItem  alloc]init]   initWithBarButtonSystemItem:                                       UIBarButtonSystemItemFlexibleSpace target:self action:nil];     
UIBarButtonItem * doneButton = [[UIBarButtonItem alloc]initWithTitle:@"Done"            style:UIBarButtonItemStyleDone  target:self action:@selector(dismissKeyBoard)]; 
NSArray * buttonsArray = [NSArray arrayWithObjects:helloButton,btnSpace,doneButton,nil]; [doneButton release]; 
[btnSpace release];
 [helloButton release]; 
[topView setItems:buttonsArray];
 [tvTextView setInputAccessoryView:topView];
 -(IBAction)dismissKeyBoard {
 [tvTextView resignFirstResponder];
 }

（4）设置UITextView圆角问题

做法是在 #import QuartzCore/QuartzCore.h 后，便能調用[textView.layer setCornerRadius:10];

（5）UITextView根据文本大小自适应高度

通过实现文本字数来确定高度，如下：

NSString * desc = @"Description it is a test font, and don't become angry for which i use to do here.Now here is a very nice party from american or not!";
CGSize size = [desc sizeWithFont:[UIFont systemFontOfSize:14] constrainedToSize:CGSizeMake(240, 2000) lineBreakMode:UILineBreakModeWordWrap];

只有UILabel需要定义的numberoflines为0，即不做行数的限制。如下：

[label setNumberOfLines:0]; 
[label setFrame:CGRectMake(40, 135, 240, size.height+10)]; 
[label setText:desc];

（6）UITextView自定选择文字后的菜单

在ViewDidLoad中加入：

UIMenuItem *menuItem = [[UIMenuItem alloc]initWithTitle:@"分享到新浪微博" action:@selector(changeColor:)]; 
UIMenuController *menu = [UIMenuController sharedMenuController];
 [menu setMenuItems:[NSArray arrayWithObject:menuItem]]; 
[menuItem release];

当然上面那个@selector里面的changeColor方法还是自己写吧，也就是说点击了我们自定义的菜单项后会触发的方法。

然后还得在代码里加上一个方法：

-(BOOL)canPerformAction:(SEL)action withSender:(id)sender {
 if(action ==@selector(changeColor:)) {
 if(textView.selectedRange.length>0) return YES; 
} return NO; 
}

 点击非输入框时隐藏键盘

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    [usertf resignFirstResponder];
    [paswldtf resignFirstResponder];
}