判断到达窗口底部

判断页面滚动到底部事件。

android上面低码。

mWebView = (WebView) findViewById(R.id.webView1);
        mWebView.setHorizontalScrollBarEnabled(false);
        mWebView.setScrollBarStyle(WebView.SCROLLBARS_OUTSIDE_OVERLAY);
        // mWebView.setScrollBarStyle(SCROLLBARS_INSIDE_OVERLAY);
        WebSettings webSetting = mWebView.getSettings();
        webSetting
                .setLayoutAlgorithm(WebSettings.LayoutAlgorithm.SINGLE_COLUMN);
        webSetting.setJavaScriptEnabled(true);
        webSetting.setAllowFileAccess(true);
 
        mWebView.loadUrl("file:///android_asset/test.html");
 
        mWebView.setWebChromeClient(new WebChromeClient() {
 
            // onJsAlert()函数接收到来自HTML网页的alert()警告信息
            public boolean onJsAlert(WebView view, String url, String message,
                    JsResult result) {
                if (message.length() != 0) {
                    AlertDialog.Builder builder = new AlertDialog.Builder(
                            TestActivity.this);
                    builder.setTitle("From JavaScript").setMessage(message)
                            .show();
                    result.cancel();
                    return true;
                }
                return false;
            }
        });

html页面中的js代码

window.onscroll = function() {
        var a = document.documentElement.scrollTop == 0 ? document.body.clientHeight
                : document.documentElement.clientHeight;
        var b = document.documentElement.scrollTop == 0 ? document.body.scrollTop
                : document.documentElement.scrollTop;
        var c = document.documentElement.scrollTop == 0 ? document.body.scrollHeight
                : document.documentElement.scrollHeight;
 
        if (a + b == c) {
            alert("OnTheEnd");
        }
    }