drop-down-menu

问题 Excuse my lack of knowledge as i am fairly new to ReactJS. I'm trying to create a dynamic Dropdown system where i have The Country DropDown and the cities DropDown, and i want to fetch my data from a const that has multiple arrays in it, here's an example of the const i have: const countries = {"France":["Paris","Marseille","Lille","Lyon"], "Usa":["New York","San Francisco","Austin","Dallas"] }; I know that i need to use the useState and the useEffect hooks and a function to handle the event

问题 I wonder how I can get this dropdown menu open its childrens from top to bottom instead from left to right? Having the li's inside the ul's open up horizontally instead of vertically. Also I want to make a specific list visible and not hidden like all others. I tried to label this ul with a own class named 'last' and making it visible with CSS... I have no experience using CSS. Thank you very much. ul { list-style: none; padding: 0; margin: 0; } ul.last { visibility: visible; list-style: none

问题 I wonder how I can get this dropdown menu open its childrens from top to bottom instead from left to right? Having the li's inside the ul's open up horizontally instead of vertically. Also I want to make a specific list visible and not hidden like all others. I tried to label this ul with a own class named 'last' and making it visible with CSS... I have no experience using CSS. Thank you very much. ul { list-style: none; padding: 0; margin: 0; } ul.last { visibility: visible; list-style: none

问题 Below is a simplified version of the input dropdown I am working with. A basic summary of what it does is: if you focus on the input, a dropdown appears. If you click one of the options in the dropdown, the option populates the input and the dropdown disappears. This is achieved using onfocus and a functions I called dropdown(); and undropdown(); . I'm in a dilemma, where I'm unable to make the dropdown disappear when someone clicks elsewhere. If I use onblur , it successfully hides the

问题 Below is a simplified version of the input dropdown I am working with. A basic summary of what it does is: if you focus on the input, a dropdown appears. If you click one of the options in the dropdown, the option populates the input and the dropdown disappears. This is achieved using onfocus and a functions I called dropdown(); and undropdown(); . I'm in a dilemma, where I'm unable to make the dropdown disappear when someone clicks elsewhere. If I use onblur , it successfully hides the

问题 I was following the example on how to handle multiple dependent widgets on jupyter notebooks from here: Dynamically changing dropdowns in IPython notebook widgets and Spyre In that example the code solution was the following: from IPython.html import widgets from IPython.display import display geo={'USA':['CHI','NYC'],'Russia':['MOW','LED']} def print_city(city): print city def select_city(country): cityW.options = geo[country] scW = widgets.Dropdown(options=geo.keys()) init = scW.value cityW

问题 I do not found the answer to this question, someone may have answered to this question yet, but: how can I make dropdown menu for example to this animated menu: Animated transform from three lines menu to cross I would want something like this, but with the above animated menu: https://www.w3schools.com/howto/tryit.asp?filename=tryhow_js_mobile_navbar Thanks for answers ! 回答1: Its so easy you can try to use this code from the link that you gave i took this for you : function myFunction() {

问题 I do not found the answer to this question, someone may have answered to this question yet, but: how can I make dropdown menu for example to this animated menu: Animated transform from three lines menu to cross I would want something like this, but with the above animated menu: https://www.w3schools.com/howto/tryit.asp?filename=tryhow_js_mobile_navbar Thanks for answers ! 回答1: Its so easy you can try to use this code from the link that you gave i took this for you : function myFunction() {

问题 I got this ArrayList of objects, and i need to set it as my spinner's adapter like this: ArrayList<Contact> contactlist= new ArrayList<Contact>(); contactlist.add("Gabe"); contactlist.add("Mark"); contactlist.add("Bill"); contactlist.add("Steve"); ArrayAdapter adapter = new ArrayAdapter(this, android.R.layout.simple_spinner_item, contactlist); adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); contactsSpinner.setAdapter(adapter); This is a example of my Contact

问题 I asked previously a question about how to make a dropdown menu by css. Now I've got it to work beautifully. But now I need to make it react to on click. The menu I'm trying to create will have 2 sets of nested list items. I'm using pseudo selecter :focus on the first level list items. But of course I lose the focus part when I'm trying to display the nested list item. Is it possible in some way to keep the first level list item to stay focused while the user goes deeper in the menu? My html