根据不同分辨率下载文档及打开文档

	private class DownloadClass implements DownloadListener{

		@Override
		public void onDownloadStart(String url, String userAgent, String contentDisposition, String mimetype, long contentLength) {
			Log.i("trans", "DownloadClass url:"+url);
			if (url.endsWith(".jpg") || url.endsWith(".png")) {
				webView.loadDataWithBaseURL(null, "<img  src=" + url + ">", "text/html", "charset=UTF-8", null);
			} else if (url.endsWith(".doc") || url.endsWith(".docx")
					|| url.endsWith(".xls") || url.endsWith(".xlsx")
					|| url.endsWith(".ppt") || url.endsWith(".pptx")
					|| url.endsWith(".pdf")) {
				//处理文档代码
			}

		}
		
	}

	private void setScale(){
		WindowManager wm = (WindowManager) mActivity.getSystemService(Context.WINDOW_SERVICE);
		DisplayMetrics outMetrics = new DisplayMetrics();
		wm.getDefaultDisplay().getMetrics(outMetrics);
		int width = outMetrics.widthPixels;
		Log.i("trans", "width:"+width);

		if(width > 650)
			webView.setInitialScale(190);
		else if(width > 520)
			webView.setInitialScale(160);
		else if(width > 450)
			webView.setInitialScale(140);
		else if(width > 300)
			webView.setInitialScale(120);
		else
			webView.setInitialScale(100);
	}

//create函数里添加以下一行
		webView.setDownloadListener(new DownloadClass());