我是相当新的XCode的 - 我设计一个应用程序与只是显示加载我的jQuery Mobile的网站一个UIWebView的单一视图。
我有到位的启动图像为Default.png和Default@2x.png文件。 当我在我的测试设备上或在模拟器中运行的应用程序,它显示了我的启动图像,然后闪烁白屏而UIWebView中加载的第一页。
我知道我可以改变背景颜色和透明度,因此会闪烁不同颜色较白,但我想,以防止闪存完全。 我想该应用程序推出,显示启动图像,而不是显示UIWebView中,直到第一个页面完全加载。 救命?
@安德烈亚斯Volz的(和其他人想知道如何解决了白色的“闪光”的问题)
首先,添加name-of-loading-image.png
和name-of-loading-image@2x.png
文件到您的Xcode项目。 常规形象应该是320×460,和@2x
的图像应该是640×920。
然后,在我的ViewController.h
文件我加了这些属性:
@property (nonatomic, retain) UIWebView *webView;
@property(nonatomic, strong) UIImageView *loadingImageView;
@end
然后在我ViewController.m
文件中添加此:
#import "ViewController.h"
@interface ViewController ()
@end
@implementation ViewController;
@synthesize webView;
@synthesize loadingImageView;
- (void)viewDidLoad
{
[super viewDidLoad];
//**************** Set website URL for UIWebView
[webView loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:@"http://www.example.com"] cachePolicy:NSURLCacheStorageAllowed timeoutInterval:20.0]];
//**************** Add Static loading image to prevent white "flash" ****************/
UIImage *loadingImage = [UIImage imageNamed:@"name-of-loading-image.png"];
loadingImageView = [[UIImageView alloc] initWithImage:loadingImage];
loadingImageView.animationImages = [NSArray arrayWithObjects:
[UIImage imageNamed:@"name-of-loading-image.png"],
nil];
[self.view addSubview:loadingImageView];
}
- (void)webViewDidFinishLoad:(UIWebView *)webView {
// Remove loading image from view
[loadingImageView removeFromSuperview];
}
要知道,当你的web视图加载完成后,你必须实现UIWebViewDelegate协议。
在你的viewController的.h文件中:
@interface viewController : UIViewController <UIWebViewDelegate>
{
UIWebView *webView;
}
@end
然后在你的viewController的.m文件,添加以下方法:
- (void)webViewDidFinishLoad:(UIWebView *)webView {
NSLog(@"content loading finished");
// Display your webView
[self.view addSubview:webView];
}
您可以使用-viewDidLoad方法在你的viewController的.M继续显示您的启动图像。 您也可以开始为您的视图内容加载:
- (void)viewDidLoad {
[super viewDidLoad];
// continue to display launch image
UIImage *launchImage = [[UIImage alloc] initWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"launchImage.png" ofType:nil ]];
UIImageView *launchImageView = [[[UIImageView alloc] initWithImage:launchImage] autorelease];
[self.view addSubview:launchImageView];
// now setup the base view for the webView controller
UIView *contentView = [[UIView alloc] initWithFrame:[[UIScreen mainScreen] applicationFrame]];
contentView.backgroundColor = [UIColor blueColor];
// for rotation
contentView.autoresizingMask = (UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight);
self.view = contentView;
//create a frame to size and place the web view
CGRect webFrame = [[UIScreen mainScreen] applicationFrame];
UIWebView *aWebView = [[UIWebView alloc] initWithFrame:webFrame];
self.webView = aWebView;
//aWebView.scalesPageToFit = YES;
aWebView.autoresizesSubviews = YES;
aWebView.autoresizingMask=(UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth);
//set the web view delegates for the web view to be itself
[aWebView setDelegate:self];
//determine the path the to the index.html file in the Resources directory
NSURL *url = [[NSBundle mainBundle] URLForResource:@"index" withExtension:@"html"];
NSURLRequest *requestObj = [NSURLRequest requestWithURL:url];
[aWebView loadRequest:requestObj];
}