iOS7 UIWebview加載進度條實現

不一樣於WKWebview，wk是有本身的加載進度值的，咱們能夠直接經過kvo檢測到，並顯示到進度條內。

 

但若是咱們爲了適配ios7，只能使用UIWebview了，這裏的加載進度，就比較尷尬了

 

因此咱們的實現方式就是：模擬進度-俗稱假進度。

 

實現原理：

自定義一個UIView的進度條，添加到Nav下方，給予兩個方法：

一、startLoadingAnimation  開始加載

二、endLoadingAnimation  結束加載

 

開始加載，先動畫模擬一個0.4s的加載，加載寬度爲0.6倍屏幕寬度，動畫結束，再0.4s實現，總共0.8倍的屏幕寬度。

結束動畫，動畫模擬1.0倍數的屏幕寬度，實現所有加載完成，並最後隱藏掉進度條。

 

代碼：

.h文件

#import <UIKit/UIKit.h>

@interface WebviewProgressLine : UIView

//進度條顏色
@property (nonatomic,strong) UIColor  *lineColor;

//開始加載
-(void)startLoadingAnimation;

//結束加載
-(void)endLoadingAnimation;

@end

 

.m文件

#import "WebviewProgressLine.h"

@implementation WebviewProgressLine

-(instancetype)initWithFrame:(CGRect)frame{
    self = [super initWithFrame:frame];
    if (self) {
        self.hidden = YES;
        self.backgroundColor = [UIColor whiteColor];
    }
    return self;
}

-(void)setLineColor:(UIColor *)lineColor{
    _lineColor = lineColor;
    self.backgroundColor = lineColor;
}

-(void)startLoadingAnimation{
    self.hidden = NO;
    self.width = 0.0;
    
    __weak UIView *weakSelf = self;
    [UIView animateWithDuration:0.4 animations:^{
        weakSelf.width = KScreenWidth * 0.6;
    } completion:^(BOOL finished) {
        [UIView animateWithDuration:0.4 animations:^{
            weakSelf.width = KScreenWidth * 0.8;
        }];
    }];
    
    
}

-(void)endLoadingAnimation{
    __weak UIView *weakSelf = self;
    [UIView animateWithDuration:0.2 animations:^{
        weakSelf.width = KScreenWidth;
    } completion:^(BOOL finished) {
        weakSelf.hidden = YES;
    }];
}

@end

 

webview頁面使用：

#import "webviewViewController.h"
#import "WebviewProgressLine.h"

@interface webviewViewController ()<UIWebViewDelegate>
@property (nonatomic,strong) UIWebView  *webview;
@property (nonatomic,strong) WebviewProgressLine  *progressLine;

@end

@implementation webviewViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    self.view.backgroundColor = [UIColor whiteColor];
    
    self.webview = [[UIWebView alloc] initWithFrame:self.view.frame];
    self.webview.delegate = self;
    [self.view addSubview:self.webview];
    
    self.progressLine = [[WebviewProgressLine alloc] initWithFrame:CGRectMake(0, 64, KScreenWidth, 3)];
    self.progressLine.lineColor = [UIColor redColor];
    [self.view addSubview:self.progressLine];
    
    
    NSURL *url = [NSURL URLWithString:@"https://www.baidu.com"];
    [self.webview loadRequest:[NSURLRequest requestWithURL:url]];
    
}

-(void)webViewDidStartLoad:(UIWebView *)webView{
    [self.progressLine startLoadingAnimation];
}

-(void)webViewDidFinishLoad:(UIWebView *)webView{
    [self.progressLine endLoadingAnimation];
}

-(void)webView:(UIWebView *)webView didFailLoadWithError:(NSError *)error{
    [self.progressLine endLoadingAnimation];
}

 

因爲內容比較簡單，就不放Demo了，直接貼代碼，你們能夠試一下～