启动图像后，XCode阻止UIWebView闪烁白屏 [英] XCode Prevent UIWebView flashing white screen after Launch Image

问题描述

我是XCode的新手 - 我正在设计一个带有单一视图的应用程序，它只显示一个加载我的jQuery移动网站的UIWebView。

I am fairly new to XCode - I'm designing an app with a single view that just displays a UIWebView that loads my jQuery mobile web site.

我有适用于启动图像的Default.png和[e-mail]文件。当我在我的测试设备或模拟器上运行应用程序时，它会显示我的启动图像，然后在UIWebView加载第一页时闪烁白屏。

I have the Default.png and [e-mail] files for the Launch images in place. When I run the app on my test device or in the emulator, it shows my Launch Image, and then flashes a white screen while the UIWebView loads the first page.

我知道我可以改变背景颜色和不透明度，因此它会闪烁不同于白色的颜色，但我想完全阻止闪光。我希望应用程序启动，显示启动图像，并且在第一页完全加载之前不显示UIWebView。帮助？

I know that I can change the background color and opacity so it will flash a different color than white, but I would like to prevent the flash altogether. I would like the app to launch, show the Launch image, and not show the UIWebView until the first page has completely loaded. Help?

推荐答案

@Andreas Volz（还有其他人想知道我是如何解决白色闪光的问题）

@ Andreas Volz (and anyone else wondering how I solved the problem of the white "flash")

首先，添加 name-of-loading-image.png 和加载名称[e-mail] 文件到你的Xcode项目。常规图像应为320 x 460， @ 2x 图像应为640 x 920。

First, add the name-of-loading-image.png and [e-mail] files to your Xcode project. The regular image should be 320 x 460, and the @2x image should be 640 x 920.

然后，在我的 ViewController.h 文件中，我添加了以下属性：

Then, in my ViewController.h file I added these properties:

@property (nonatomic, retain) UIWebView *webView;
@property(nonatomic, strong) UIImageView *loadingImageView;
@end

然后在我的 ViewController.m中 file我添加了这个：

And then in my ViewController.m file I added this:

#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];

}

这篇关于启动图像后，XCode阻止UIWebView闪烁白屏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！