在UIWebview上显示本地UIImage [英] Display local UIImage on UIWebview
问题描述
我的设置：
我的iPhone应用程序中有一个webview，请访问www.mysite.com。
My setup:
I have a webview in my iPhone app, going to www.mysite.com.
试验
如果我将backgroundcolor uicolor clearcolor设置为我的webview并在我的webview后面绘制一个uiimage，它将无法使用我的webview滚动！
Trials
If I set "backgroundcolor uicolor clearcolor" to my webview and draw an uiimage behind my webview, it won't scroll with my webview!
我的问题：
我想将图像添加到webview中。此外，此图像应存储在iPhone应用程序中，而不是存储在网络服务器上（当然，如果我将图像放在网络服务器上，我只需将其作为背景用CSS绘制）。
My problem:
I would like the image to with the webview. Also, this image should be stored in the iPhone app and not on the webserver (Of course, if I put the image on the webserver I can simply draw it as background with CSS).
通过html / javascript / Objective C访问此图像的最佳方式是什么，所以我可以看到这个本地图像作为我网站的背景？有办法吗？
What is the best way to access this image via html/javascript/Objective C, so I can see this local image as background of my website? Is there a way at all?
推荐答案
你有几个选择。你可以加载一个baseURL
You have a couple of options. You can load the page with a baseURL of
[[NSBundle mainBundle] bundleURL]
或者您可以使用javascript使用以下方法设置图像的路径。
or you can use javascript to set the path to your image using the following method.
[[NSBundle mainBundle] URLForResource:@"myimage" withExtension:@"png"]
编辑：检查这里链接到WebView内部的资源 - iPhone 。看起来您将使用pathForResource而不是URLForResource。
Check here Link to resources inside WebView - iPhone. It looks like you will use pathForResource rather than URLForResource.
编辑2：您可能希望使用数据URI将您自己的本地文件添加到网站。
Edit 2: You may want to use Data URI's to add your own local files to the web site.
YourCode.m
YourCode.m
#import "NSString+DataURI.h"
#import "NSData+Base64.h"
...
-(void)webViewDidFinishLoad:(UIWebView *)webView
{
NSString *imgPath = [[NSBundle mainBundle] pathForResource:@"image" ofType:@"png"];
NSData *imgData = [NSData dataWithContentsOfFile:imgPath];
NSString *imgB64 = [[imgData base64Encoding] pngDataURIWithContent];
NSString *javascript = [NSString stringWithFormat:@"document.body.style.backgroundImage='url(%@)';", imgB64];
[webView stringByEvaluatingJavaScriptFromString:javascript];
}
以下代码我没有写，而且我不确定原点
The following code I DID NOT WRITE and I am not sure of the origin
NSData + Base64.h
NSData+Base64.h
@interface NSData (Base64)
+ (NSData *)dataWithBase64EncodedString:(NSString *)string;
- (id)initWithBase64EncodedString:(NSString *)string;
- (NSString *)base64Encoding;
- (NSString *)base64EncodingWithLineLength:(unsigned int) lineLength;
@end
NSData.Base64.m
NSData.Base64.m
#import "NSData+Base64.h"
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','+','/' };
@implementation NSData (VQBase64)
- (id)initWithString:(NSString *)string {
if ((self = [super init])) {
[self initWithBase64EncodedString:string];
}
return self;
}
+ (NSData *) dataWithBase64EncodedString:(NSString *) string {
return [[[NSData allocWithZone:nil] initWithBase64EncodedString:string] autorelease];
}
- (id) initWithBase64EncodedString:(NSString *) string {
NSMutableData *mutableData = nil;
if( string ) {
unsigned long ixtext = 0;
unsigned long lentext = 0;
unsigned char ch = 0;
unsigned char inbuf[4], outbuf[3];
short i = 0, ixinbuf = 0;
BOOL flignore = NO;
BOOL flendtext = NO;
NSData *base64Data = nil;
const unsigned char *base64Bytes = nil;
// Convert the string to ASCII data.
base64Data = [string dataUsingEncoding:NSASCIIStringEncoding];
base64Bytes = [base64Data bytes];
mutableData = [NSMutableData dataWithCapacity:[base64Data length]];
lentext = [base64Data length];
while( YES ) {
if( ixtext >= lentext ) break;
ch = base64Bytes[ixtext++];
flignore = NO;
if( ( ch >= 'A' ) && ( ch <= 'Z' ) ) ch = ch - 'A';
else if( ( ch >= 'a' ) && ( ch <= 'z' ) ) ch = ch - 'a' + 26;
else if( ( ch >= '0' ) && ( ch <= '9' ) ) ch = ch - '0' + 52;
else if( ch == '+' ) ch = 62;
else if( ch == '=' ) flendtext = YES;
else if( ch == '/' ) ch = 63;
else flignore = YES;
if( ! flignore ) {
short ctcharsinbuf = 3;
BOOL flbreak = NO;
if( flendtext ) {
if( ! ixinbuf ) break;
if( ( ixinbuf == 1 ) || ( ixinbuf == 2 ) ) ctcharsinbuf = 1;
else ctcharsinbuf = 2;
ixinbuf = 3;
flbreak = YES;
}
inbuf [ixinbuf++] = ch;
if( ixinbuf == 4 ) {
ixinbuf = 0;
outbuf [0] = ( inbuf[0] << 2 ) | ( ( inbuf[1] & 0x30) >> 4 );
outbuf [1] = ( ( inbuf[1] & 0x0F ) << 4 ) | ( ( inbuf[2] & 0x3C ) >> 2 );
outbuf [2] = ( ( inbuf[2] & 0x03 ) << 6 ) | ( inbuf[3] & 0x3F );
for( i = 0; i < ctcharsinbuf; i++ )
[mutableData appendBytes:&outbuf[i] length:1];
}
if( flbreak ) break;
}
}
}
self = [self initWithData:mutableData];
return self;
}
#pragma mark -
- (NSString *) base64Encoding {
return [self base64EncodingWithLineLength:0];
}
- (NSString *) base64EncodingWithLineLength:(unsigned int) lineLength {
const unsigned char *bytes = [self bytes];
NSMutableString *result = [NSMutableString stringWithCapacity:[self length]];
unsigned long ixtext = 0;
unsigned long lentext = [self 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;
if( lineLength > 0 ) {
if( charsonline >= lineLength ) {
charsonline = 0;
[result appendString:@"\n"];
}
}
}
return [NSString stringWithString:result];
}
@end
NSString + DataURI.h
NSString+DataURI.h
#import <Foundation/Foundation.h>
@interface NSString(DataURI)
- (NSString *) pngDataURIWithContent;
- (NSString *) jpgDataURIWithContent;
@end
NSString + DataURI.m
NSString+DataURI.m
#import "NSString+DataURI.h"
@implementation NSString(DataURI)
- (NSString *) pngDataURIWithContent;
{
NSString * result = [NSString stringWithFormat: @"data:image/png;base64,%@", self];
return result;
}
- (NSString *) jpgDataURIWithContent;
{
NSString * result = [NSString stringWithFormat: @"data:image/jpg;base64,%@", self];
return result;
}
@end
这篇关于在UIWebview上显示本地UIImage的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
