iOS开发之如何截图and如何合并多张图片等..._IOS开发
1、UIView截图
-(UIImage*)captureView:(UIView *)theView{
CGRect rect = theView.frame;
if ([theView isKindOfClass:[UIScrollView class]]) {
rect.size = ((UIScrollView *)theView).contentSize;
}
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
[theView.layer renderInContext:context];
UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return img;
}
2、UIScrollview截图
- (UIImage *)captureScrollView:(UIScrollView *)scrollView{
UIImage* image = nil;
UIGraphicsBeginImageContext(scrollView.contentSize);
{
CGPoint savedContentOffset = scrollView.contentOffset;
CGRect savedFrame = scrollView.frame;
scrollView.contentOffset = CGPointZero;
scrollView.frame = CGRectMake(0, 0, scrollView.contentSize.width, scrollView.contentSize.height);
[scrollView.layer renderInContext: UIGraphicsGetCurrentContext()];
image = UIGraphicsGetImageFromCurrentImageContext();
scrollView.contentOffset = savedContentOffset;
scrollView.frame = savedFrame;
}
UIGraphicsEndImageContext();
if (image != nil) {
return image;
}
return nil;
}
3、合并多张图片
- (UIImage *)composeWithHeader:(UIImage *)header content:(UIImage *)content footer:(UIImage *)footer{
CGSize size = CGSizeMake(content.size.width, header.size.height +content.size.height +footer.size.height);
UIGraphicsBeginImageContext(size);
[header drawInRect:CGRectMake(0,
0,
header.size.width,
header.size.height)];
[content drawInRect:CGRectMake(0,
header.size.height,
content.size.width,
content.size.height)];
[footer drawInRect:CGRectMake(0,
header.size.height+content.size.height,
footer.size.width,
footer.size.height)];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
4、流媒体
将音频、图片转成base64Binary
+(NSData *)base64Encoded:(NSData *)data
{
//base64binary(流媒体)
static char encodingTable[64] = {
'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P',
'Q','R','S','T','U','V','W','X','Y','Z','a','b','c','d','e','f',
'g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v',
'w','x','y','z','0','1','2','3','4','5','6','7','8','9','+','/' };
const unsigned char *bytes = [data bytes];
NSMutableString *result = [NSMutableString stringWithCapacity:[data length]];
unsigned long ixtext = 0;
unsigned long lentext = [data length];
long ctremaining = 0;
unsigned char inbuf[3], outbuf[4];
unsigned short i = 0;
unsigned short charsonline = 0, ctcopy = 0;
unsigned long ix = 0;
while( YES )
{
ctremaining = lentext - ixtext;
if( ctremaining <= 0 ) break;
for( i = 0; i < 3; i++ ) {
ix = ixtext + i;
if( ix < lentext ) inbuf[i] = bytes[ix];
else inbuf [i] = 0;
}
outbuf [0] = (inbuf [0] & 0xFC) >> 2;
outbuf [1] = ((inbuf [0] & 0x03) << 4) | ((inbuf [1] & 0xF0) >> 4);
outbuf [2] = ((inbuf [1] & 0x0F) << 2) | ((inbuf [2] & 0xC0) >> 6);
outbuf [3] = inbuf [2] & 0x3F;
ctcopy = 4;
switch( ctremaining )
{
case 1:
ctcopy = 2;
break;
case 2:
ctcopy = 3;
break;
}
for( i = 0; i < ctcopy; i++ )
[result appendFormat:@"%c", encodingTable[outbuf[i]]];
for( i = ctcopy; i < 4; i++ )
[result appendString:@"="];
ixtext += 3;
charsonline += 4;
}
return [result dataUsingEncoding:NSUTF8StringEncoding];
}
这里调用上面的方法
+(NSString *)loadingFile:(NSURL *)filepath
{
NSData * data = [[NSData alloc]initWithContentsOfURL:filepath];
NSData * base64Data = [self base64Encoded:data];
NSString * strBase64 = [[NSString alloc]initWithData:base64Data encoding:NSASCIIStringEncoding];
return strBase64;
//you can upload this base64Data to server now
}
