IOS UIWenView 調整頁面字體大小

IOS UIWenView 調整頁面字體大小，示例如下：

 

FontSizeChangeViewController.h

 

#import 

@interface FontSizeChangeViewController : UIViewController{
    UIToolbar *toolBar;
}

@property (weak, nonatomic) IBOutlet UIWebView *webDetails;


@end

 

FontSizeChangeViewController.m

#import FontSizeChangeViewController.h

#define K_FONT_SIZE_CHANGE_WEB_URL @http://3g.fx678.com/news/detail/201508031037021902
#define K_FONT_SIZE_CHANGE_KEY @ONT_SIZE_CHANGE_VIEW_SIZE

@interface FontSizeChangeViewController ()

@end

@implementation FontSizeChangeViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    [self initView];
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}


#pragma mark - Custom method
- (void) initView{

    //[S]加載網頁
    NSURL *url = [[NSURL alloc] initWithString:K_FONT_SIZE_CHANGE_WEB_URL];

    // 自適應網頁大小，支持放大縮小
    self.webDetails.scalesPageToFit = YES;

    [self.webDetails loadRequest:[NSURLRequest requestWithURL:url]];
    //[E]加載網頁

    //[S]設置toolbar
    CGSize cgsize = self.navigationController.toolbar.frame.size;

    if (!toolBar)
        toolBar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, self.view.frame.size.height- cgsize.height, cgsize.width, cgsize.height)];

    //字體放大按鈕
    UIBarButtonItem *barBtnAdd = [[UIBarButtonItem alloc] initWithTitle:@字號+ style:UIBarButtonItemStylePlain target:self action:@selector(btnFontSizeChange:)];
    barBtnAdd.tag = 1;

    //字體縮小按鈕
     UIBarButtonItem *barBtnSmall = [[UIBarButtonItem alloc] initWithTitle:@字號- style:UIBarButtonItemStylePlain target:self action:@selector(btnFontSizeChange:)];
    barBtnAdd.tag = 2;

    NSArray *arrBtns = [NSArray arrayWithObjects:barBtnAdd,barBtnSmall, nil];
    [toolBar setBarStyle:UIBarStyleDefault];
    toolBar.autoresizingMask = UIViewAutoresizingFlexibleTopMargin;
    [toolBar setItems:arrBtns animated:YES];

    [self.view addSubview:toolBar];
    //[E]設置toolbar

}


//字體大小改變
-(void) btnFontSizeChange:(UIBarButtonItem *)sender{

    NSInteger fontSize = [[NSUserDefaults standardUserDefaults] integerForKey:K_FONT_SIZE_CHANGE_KEY];
    if (!fontSize){
        //默認18px
        [[NSUserDefaults standardUserDefaults] setInteger:18 forKey:K_FONT_SIZE_CHANGE_KEY];

        fontSize = [[NSUserDefaults standardUserDefaults] integerForKey:K_FONT_SIZE_CHANGE_KEY];
    }

    NSString *strFontSize = nil;
    if (sender && [sender.title isEqualToString:@字號+])
        fontSize += 2;
    else if(sender && [sender.title isEqualToString:@字號-])
        fontSize -= 2;

    strFontSize = [NSString stringWithFormat:@document.body.style.fontSize = '%lDpx';,(long)fontSize];
    [self.webDetails stringByEvaluatingJavaScriptFromString:strFontSize];

    //更新值
    [[NSUserDefaults standardUserDefaults] setInteger:fontSize forKey:K_FONT_SIZE_CHANGE_KEY];

}

@end