0. NSLog的调试
#ifdef __OBJC__
#ifdef DEBUG
#define NSLog(fmt, ...) NSLog((@"%s [Line %d] " fmt), __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__)
#else
#define NSLog(...)
#endif
#endif
1. 退回输入键盘
- (BOOL) textFieldShouldReturn:(id)textField{ [textField resignFirstResponder];
}
2. CGRect
frame = CGRectMake (origin.x, origin.y, size.width, size.height);矩形
NSStringFromCGRect(someCG) 把 CGRect 结构转变为格式化字符串;
CGRectFromString(aString) 由字符串恢复出矩形;
CGRectInset(aRect) 创建较小或较大的矩形(中心点相同),+较小 -较大
CGRectIntersectsRect(rect1, rect2) 判断两矩形是否交叉,是否重叠
CGRectZero 高度和宽度为零的/位于(0,0)的矩形常量
3. CGPoint & CGSize
CGPoint aPoint = CGPointMake(x, y);
CGSize aSize = CGSizeMake(width, height);
4. 设置透明度
[myView setAlpha:value]; (0.0 < value < 1.0)
5. 自定义颜色
UIColor *newColor = [[UIColor alloc] initWithRed:(float) green:(float) blue:(float) alpha:(float)];
0.0~1.0
6. 屏幕
竖屏: 320X480
横屏: 480X320
横屏: [[UIApplication shareApplication] setStatusBarOrientation:UIInterfaceOrientationLandscapeRight].
屏幕变动检测: orientation == UIInterfaceOrientationLandscapeLeft
7. 隐藏状态栏
[[UIApplication shareApplication] setStatusBarHidden: YES
animated:NO]
8. 自动适应父视图大小:
aView.autoresizingSubviews = YES;
aView.autoresizingMask = (UIViewAutoresizingFlexibleWidth |
UIViewAutoresizingFlexibleHeight);
9. 图片压缩
压缩图片
用法：UIImage *yourImage= [self imageWithImageSimple:image scaledToSize:CGSizeMake(210.0, 210.0)];
压缩图片
- (UIImage*)imageWithImageSimple:(UIImage*)image scaledToSize:(CGSize)newSize
{
Create a graphics image context
UIGraphicsBeginImageContext(newSize);
Tell the old image to draw in this newcontext, with the desired
new size
[image drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];
Get the new image from the context
UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
End the context
UIGraphicsEndImageContext();
Return the new image.
return newImage;
}
10. 对图库的操作
- 1, 选择相册：
UIImagePickerControllerSourceTypesourceType=UIImagePickerControllerSourceTypeCamera;
if (![UIImagePickerControllerisSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {
sourceType=UIImagePickerControllerSourceTypePhotoLibrary;
}
UIImagePickerController * picker = [[UIImagePickerControlleralloc]init];
picker.delegate = self;
picker.allowsEditing=YES;
picker.sourceType=sourceType;
[self presentModalViewController:picker animated:YES];
- 2, 选择完毕：
-(void)imagePickerController:(UIImagePickerController*)pickerdidFinishPickingMediaWithInfo:(NSDictionary *)info
{
[picker dismissModalViewControllerAnimated:YES];
UIImage * image=[info objectForKey:UIImagePickerControllerEditedImage];
[self performSelector:@selector(selectPic:) withObject:imageafterDelay:0.1];
}
-(void)selectPic:(UIImage*)image
{
NSLog(@"image%@",image);
imageView = [[UIImageView alloc] initWithImage:image];
imageView.frame = CGRectMake(0, 0, image.size.width, image.size.height);
[self.viewaddSubview:imageView];
[self performSelectorInBackground:@selector(detect:) withObject:nil];
}
-3, 取消选择：
-(void)imagePickerControllerDIdCancel:(UIImagePickerController*)picker
{
[picker dismissModalViewControllerAnimated:YES];
}
11. Status Bar操作
隐藏Status Bar
[[UIApplication sharedApplication]setStatusBarHidden:YES animated:NO];
状态栏的网络活动风火轮是否旋转
[UIApplication sharedApplication].networkActivityIndicatorVisible，默认值是NO。
12. 键盘透明
textField.keyboardAppearance = UIKeyboardAppearanceAlert;
13. 截取屏幕图片
创建一个基于位图的图形上下文并指定大小为
CGSizeMake(200,400)
UIGraphicsBeginImageContext(CGSizeMake(200,400));
renderInContext 呈现接受者及其子范围到指定的上下文
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
返回一个基于当前图形上下文的图片
UIImage *aImage = UIGraphicsGetImageFromCurrentImageContext();
移除栈顶的基于当前位图的图形上下文
UIGraphicsEndImageContext();
以png格式返回指定图片的数据
imageData = UIImagePNGRepresentation(aImage);
14. 修改PlaceHolder的默认颜色
[username_text setValue:[UIColor colorWithRed:1 green:1 blue:1 alpha:0.5] forKeyPath:@"_placeholderLabel.textColor"];
15. 页面上移解决文本框被键盘弹出挡住的问题
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
[username_text resignFirstResponder];
[password_text resignFirstResponder];
When the user presses return, take focus away from the text field so that the keyboard is dismissed.
NSTimeInterval animationDuration = 0.30f;
[UIView beginAnimations:@"ResizeForKeyboard" context:nil];
[UIView setAnimationDuration:animationDuration];
CGRect rect = CGRectMake(0.0f, 0.0f, self.view.frame.size.width, self.view.frame.size.height);
self.view.frame = rect;
[UIView commitAnimations];
}
- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
When the user presses return, take focus away from the text field so that the keyboard is dismissed.
NSTimeInterval animationDuration = 0.30f;
[UIView beginAnimations:@"ResizeForKeyboard" context:nil];
[UIView setAnimationDuration:animationDuration];
CGRect rect = CGRectMake(0.0f, 0.0f, self.view.frame.size.width, self.view.frame.size.height);
self.view.frame = rect;
[UIView commitAnimations];
[textField resignFirstResponder];
return YES;
}
- (void)textFieldDidBeginEditing:(UITextField *)textField
{
CGRect frame = password_text.frame;
int offset = frame.origin.y + 32 - (self.view.frame.size.height - 216.0);//键盘高度216
NSTimeInterval animationDuration = 0.30f;
[UIView beginAnimations:@"ResizeForKeyBoard" context:nil];
[UIView setAnimationDuration:animationDuration];
float width = self.view.frame.size.width;
float height = self.view.frame.size.height;
if(offset > 0)
{
CGRect rect = CGRectMake(0.0f, -offset,width,height);
self.view.frame = rect;
}
[UIView commitAnimations];
}
16. iOS代码加密常用加密方式
- 1, MD5加密
.h中
#import <Foundation/Foundation.h>
@interface CJMD5 : NSObject
+(NSString *)md5HexDigest:(NSString *)input;
@end
-------------------------------------------
.m中
#import "CJMD5.h"
#import <CommonCrypto/CommonDigest.h>
@implementation CJMD5
+(NSString *)md5HexDigest:(NSString *)input{
const char* str = [input UTF8String];
unsigned char result[CC_MD5_DIGEST_LENGTH];
CC_MD5(str, strlen(str), result);
NSMutableString *ret = [NSMutableString stringWithCapacity:CC_MD5_DIGEST_LENGTH];
for(int i = 0; i<CC_MD5_DIGEST_LENGTH; i++) {
[ret appendFormat:@"%02X",result];
}
return ret;
}
@end
----------------------------------------------------------------
MD5是不可逆的只有加密没有解密，iOS代码加密使用方式如下
NSString *userName = @"cerastes";
NSString *password = @"hello Word";
MD5加密
NSString *md5 = [CJMD5 md5HexDigest:password];
NSLog(@"%@",md5);
END
- 2, AES加密
NSString *encryptedData = [AESCrypt encrypt:userName password:password];加密
NSString *message = [AESCrypt decrypt:encryptedData password:password]; 解密
NSLog(@"加密结果 = %@",encryptedData);
NSLog(@"解密结果 = %@",message);
- 3, BASE64加密iOS代码加密
.h
+ (NSString*)encodeBase64String:(NSString *)input;
+ (NSString*)decodeBase64String:(NSString *)input;
+ (NSString*)encodeBase64Data:(NSData *)data;
+ (NSString*)decodeBase64Data:(NSData *)data;
.m
+ (NSString*)encodeBase64String:(NSString * )input {
NSData *data = [input dataUsingEncoding:NSUTF8StringEncoding allowLossyConversion:YES];
data = [GTMBase64 encodeData:data];
NSString *base64String = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
return base64String;
}
+ (NSString*)decodeBase64String:(NSString * )input {
NSData *data = [input dataUsingEncoding:NSUTF8StringEncoding allowLossyConversion:YES];
data = [GTMBase64 decodeData:data];
NSString *base64String = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
return base64String;
}
// 加密
+ (NSString*)encodeBase64Data:(NSData *)data {
data = [GTMBase64 encodeData:data];
NSString *base64String = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
return base64String;
}
// 加密
+ (NSString*)decodeBase64Data:(NSData *)data {
data = [GTMBase64 decodeData:data];
NSString *base64String = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
return base64String;
}
BASE64加密
NSString *baseEncodeString = [GTMBase64 encodeBase64String:password];
NSString *baseDecodeString = [GTMBase64 decodeBase64String:baseEncodeString];
NSLog(@"baseEncodeString = %@",baseEncodeString);
NSLog(@"baseDecodeString = %@",baseDecodeString);
17. 版本比较
+ (BOOL)isVersion:(NSString*)versionA biggerThanVersion:(NSString*)versionB
{
NSArray *arrayNow = [versionB componentsSeparatedByString:@"."];
NSArray *arrayNew = [versionA componentsSeparatedByString:@"."];
BOOL isBigger = NO;
NSInteger i = arrayNew.count > arrayNow.count? arrayNow.count : arrayNew.count;
NSInteger j = 0;
BOOL hasResult = NO;
for (j = 0; j < i; j ++) {
NSString* strNew = [arrayNew objectAtIndex:j];
NSString* strNow = [arrayNow objectAtIndex:j];
if ([strNew integerValue] > [strNow integerValue]) {
hasResult = YES;
isBigger = YES;
break;
}
if ([strNew integerValue] < [strNow integerValue]) {
hasResult = YES;
isBigger = NO;
break;
}
}
if (!hasResult) {
if (arrayNew.count > arrayNow.count) {
NSInteger nTmp = 0;
NSInteger k = 0;
for (k = arrayNow.count; k < arrayNew.count; k++) {
nTmp += [[arrayNew objectAtIndex:k]integerValue];
}
if (nTmp > 0) {
isBigger = YES;
}
}
}
return isBigger;
}
18. setValue： forKey：的定义
@interface NSMutableDictionary(NSKeyValueCoding)
/* Send -setObject:forKey: to the receiver, unless the value is nil, in which case send -removeObject:forKey:.
*/
- (void)setValue:(id)value forKey:(NSString *)key;
@end
value 为 nil ，调用 removeObject:forKey:
value不为nil时调用 setObject：forKey：
key为NSString类型。
2 setObject：forKey：的定义
@interface NSMutableDictionary : NSDictionary
- (void)removeObjectForKey:(id)aKey;
- (void)setObject:(id)anObject forKey:(id <NSCopying>)aKey;
@end
anobject不能为nil，而且key是一个id类型，不仅限于NSString类型
两者的区别：
- （1）setObject：forkey：中value是不能够为nil的；setValue：forKey：中value能够为nil，但是当value为nil的时候，会自动调用removeObject：forKey方法
- （2）setValue：forKey：中key只能够是NSString类型，而setObject：forKey：的可以是任何类型
待续...
