how to detect chrome camera access dialog is open

Question

我如何才能检测到Google Chrome浏览器访问对话框是否打开，我可以检测到用户选择了允许还是拒绝，但是无法检测到对话框是否打开，我需要在其下方显示一个小提示，以了解是否需要打开对话框。我默认打开它，但是如果用户第二次拒绝，则它不会打开

Answer 1

I don't believe that there's actually a way to detect if the dialog is open, but you might be able to infer that it's open. Show your tip each time you call getUserMedia() , and hide it on the callback or any other user interaction with your page (assumption being they denied video access if they're doing other stuff on the page)...

$("#tooltip").show();

navigator.webkitGetUserMedia({"video":true}, function(stream) {
    $("#tooltip").hide();
    // Do your thing.
});

You could also put a delay on showing the tip so it's only shown if the video stream callback doesn't happen for a specified period of time:

var tipTimeout = setTimeout(function() {
    $("#tooltip").show();
}, 1000);

navigator.webkitGetUserMedia({"video":true}, function(stream) {
    clearTimeout(tipTimeout);
    $("#tooltip").hide();
    // Do your thing.
});

Hope this helps!