Ios WebViewJavascriptBridge在解除ViewController时不会再次调用

当视图第一次显示时，js事件正常运行。然后我使用

presentViewController

显示我单击的图像。

dismissViewController

后，返回webView，再次单击图像，但js callHandler不会运行。这是我的密码

// oc file code

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    if (_bridge) { return; }

    _bridge = [WebViewJavascriptBridge bridgeForWebView:self.webView];

    [_bridge registerHandler:@"jsImagesList" handler:^(id data, WVJBResponseCallback responseCallback) {
        self.imageList = data;
    }];

    [_bridge registerHandler:@"openImageOnIndex" handler:^(id data, WVJBResponseCallback responseCallback) {
        [self openImageOnIndex:data];// use MWPhotoBrowser to show the image
    }];
}

// js file code

function setupWebViewJavascriptBridge(callback) {
    // just copy from WebViewJavascriptBridge
}

setupWebViewJavascriptBridge(function(bridge) {

    var objs = document.getElementsByTagName("img");
    var images = [];
    for(var i=0;i<objs.length;i++) {
        images.push(objs[i].src);
        objs[i].setAttribute('data-index',i);
        objs[i].onclick = function(){

            // just for test, let me know I can click the img
            document.body.style.backgroundColor = '#'+Math.floor(Math.random()*0xFFFFFF).toString(16);

            var di = this.getAttribute('data-index');

            // ----------- question -----------
            // first time it run, but when dismissViewController, it not run
            bridge.callHandler('openImageOnIndex', {'i': di}, function(response) {})
        }
    }
    bridge.callHandler('jsImagesList', images, function(response) {})
})

//oc文件代码
-（无效）视图将显示：（BOOL）动画{
[超级视图将显示：动画]；
if（_桥）{return；}
_bridge=[WebViewJavascriptBridge bridgeForWebView:self.webView]；
[_桥寄存器句柄：@“jsImagesList”句柄：^（id数据，WVJBResponseCallback responseCallback）{
self.imageList=数据；
}];
[_桥寄存器句柄：@“openImageOnIndex”句柄：^（id数据，WVJBResponseCallback responseCallback）{
[self-openImageOnIndex:data]；//使用MWPhotoBrowser显示图像
}];
}
//js文件代码
函数setupWebViewJavascriptBridge（回调）{
//只需从WebViewJavascriptBridge复制即可
}
setupWebViewJavascriptBridge（函数（桥）{
var objs=document.getElementsByTagName（“img”）；
var图像=[]；
对于（var i=0；i