iPhone控件之UITextView

//
//  UITestViewController.h
//  UITest
//

#import <UIKit/UIKit.h>

@interface UITestViewController : UIViewController <UITextViewDelegate>
{

}

@end

//
//  UITestViewController.m
//  UITest
//

#import "UITestViewController.h"

UIScrollView *myScrollView;
UITextView *myTextView;

@implementation UITestViewController

-(void)buttonClick:(id)sender
{
[myTextView resignFirstResponder];
}

- (void)viewDidLoad {

[super viewDidLoad];

CGRect viewRect = [self.view bounds];
myScrollView = [[UIScrollView alloc] initWithFrame:viewRect];
myScrollView.contentSize = viewRect.size;
[self.view addSubview:myScrollView];

CGRect buttonFrame = CGRectMake(10,10,60,32);
UIButton *keyboardToggle = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[keyboardToggle setTitle:@"hide" forState:UIControlStateNormal];
[keyboardToggle addTarget:self action:@selector(buttonClick:) forControlEvents:UIControlEventTouchUpInside];
keyboardToggle.frame = buttonFrame;
[myScrollView addSubview:keyboardToggle];

CGRect textRect = CGRectMake(10,60,300,200);
myTextView = [[UITextView alloc] initWithFrame:textRect];

myTextView.font = [UIFont systemFontOfSize:22.0];

myTextView.keyboardType = UIKeyboardTypeDefault;
myTextView.returnKeyType = UIReturnKeyGo;

//uncomment to enable data detectors
//myTextView.text = @"this is a link: http://google.com ";
//myTextView.dataDetectorTypes = UIDataDetectorTypeAll;
//myTextView.enabled = NO;

myTextView.delegate = self;

[myScrollView addSubview:myTextView];

[myTextView release];
[myScrollView release];
}

- (void)textViewDidBeginEditing:(UITextView *)textView
{
float keyboardHeight;
if ([UIDevice currentDevice].orientation == UIDeviceOrientationPortrait | UIDeviceOrientationPortraitUpsideDown)
keyboardHeight = 216.0;
else
keyboardHeight = 162.0;

CGRect textViewRect = textView.frame;
float textViewBottom = textViewRect.origin.y + textViewRect.size.height;

CGRect viewRect = [myScrollView bounds];
float keyboardTop = viewRect.size.height-keyboardHeight;

float scrollOffset = fabs(textViewBottom - keyboardTop);

[myScrollView setContentOffset:CGPointMake(0, scrollOffset) animated:YES];
}

- (void)textViewDidEndEditing:(UITextView *)textView
{
[myScrollView setContentOffset:CGPointMake(0, 0) animated:YES];
}
- (void)didReceiveMemoryWarning {
// Releases the view if it doesn't have a superview.
[super didReceiveMemoryWarning];

// Release any cached data, images, etc that aren't in use.
}

- (void)viewDidUnload {
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}

- (void)dealloc {
[super dealloc];
}

@end

一种简单的按回车键后，键盘弹起的操作，实现UITextViewDelegate的下属方法：

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