用于检测焦点是否在文本字段中的Javascript代码

Question

I'm trying to make a safari extension that does something if the cursor focus isn't in a text field. However the following code to detect if the focus isn't in a text field does not work.

    if ($(document.activeElement).attr("type") != "text" 
       && $(document.activeElement).attr("type") != "textarea") {
          ..do something
    }

Answer 1

Just keep it simple:

var el = document.activeElement;

if (el && (el.tagName.toLowerCase() == 'input' && el.type == 'text' ||
    el.tagName.toLowerCase() == 'textarea')) {
  // focused element is a text input or textarea
} 

Answer 2

You can use jquery to achive this

$('input[type="text"]').focus(function() {
   alert('Focused');
});

Answer 3

$("input[type=text]").filter(":not(:focus)").css("background","#ff0000");

$("input[type=text]").focus(function(){
    $(this).css("background","#ffffff");
});

$("input[type=text]").blur(function(){
    $(this).css("background","#ff0000");
});

Should set all the non-active inputs' background to red. (Worked in Chrome 18)