frontend

setState vs replaceState in React.js

谁都会走 提交于 2019-11-28 15:42:49
问题 I am new to React.js Library and I was going over some of the tutorials and I came across: this.setState this.replaceState The Description given is not very clear (IMO). setState is done to 'set' the state of a value, even if its already set in the 'getInitialState' function. Similarly, The replaceState() method is for when you want to clear out the values already in state, and add new ones. I tried this.setState({data: someArray}); followed by this.replaceState({test: someArray}); and then

Convert javascript array to string

拟墨画扇 提交于 2019-11-28 15:22:06
I'm trying to iterate over a "value" list and convert it into a string. Here is the code: var blkstr = $.each(value, function(idx2,val2) { var str = idx2 + ":" + val2; alert(str); return str; }).get().join(", "); alert() function works just fine and displays the proper value. But somehow, jquery's .get() function doesn't get the right sort of object and fails. What am I doing wrong? If value is associative array, such code will work fine: var value = { "aaa": "111", "bbb": "222", "ccc": "333" }; var blkstr = []; $.each(value, function(idx2,val2) { var str = idx2 + ":" + val2; blkstr.push(str);

How a CSS pixel size is calculated?

我只是一个虾纸丫 提交于 2019-11-28 15:21:04
While delving into CSS units I've encountered a definition of the reference pixel. However, I wasn't able to find a consistent and comprehensive description of its relation to the CSS pixel unit. I've done some research on this matter, yet it's still a little bit unclear to me. 1. Gathered information 1.1 A pixel definition There are two distinct types/definitions of a pixel: "Device pixel" — a single physical point on a display. And: CSS pixel — a unit most closely matching the reference pixel. [ 1 ] Two parallel concepts under the same name definitely don't clarify the confusion. I fully

What are the most common font-sizes for H1-H6 tags [closed]

 ̄綄美尐妖づ 提交于 2019-11-28 15:01:29
I've always been unsure of where to start as a general best practice baseline. Yes, I know it depends on your design -- but what's most common? Here's what I currently have as a starter: h1 { font-size: 24px;} h2 { font-size: 22px;} h3 { font-size: 18px;} h4 { font-size: 16px;} h5 { font-size: 12px;} h6 { font-size: 10px;} Yes, we don't use EMs at my current job. Thanks Donut It would depend on the browser's default stylesheet. You can view an (unofficial) table of CSS2.1 User Agent stylesheet defaults here . Based on the page listed above, the default sizes look something like this: IE7 IE8

How to check if a tab has been reloaded in background.js?

拈花ヽ惹草 提交于 2019-11-28 14:15:43
I am writing a Chrome extension which needs to detect if the tab has been reloaded, that is to say, the user refreshed the page (either by pressing the refresh button, or put a cursor behind the URL and press Enter) with no URL change. If it happens, then I will reinitialize my variables defined in background.js . I am wondering how could I get this " is_reload " boolean value? I tried to make use of windows.performance.navigation.type , but it doesn't have any effect in the background.js . Use webNavigation The API to use from a script in the background context to determine when a page is

Always display bootstrap-datepicker, not just on focus

你离开我真会死。 提交于 2019-11-28 13:35:54
I'm using the bootstrap-datepicker library to create a datepicker to let the user choose the date. I would like to always display the picker, not just when the user clicks on an input field or a button. How can I do this? First, make sure you're using the latest version of the library, which is currently 1.2.0. The original version by eyecon is pretty poorly documented and I don't know if it can do what you want. There are a couple of ways to solve your problem. Use whichever of these you prefer: Create an embedded/inline datepicker and then add a changeDate handler to it. You'll want HTML

onEnter prop in react-router v4

為{幸葍}努か 提交于 2019-11-28 10:32:44
I'm using react-router v4 . I find it confusing that when I click on <Link> component, the route is immediately changed. I want to stay at the current route before I fetch the data, not to switch the route and then fetch the data. I find that in react-router v3 there's a onEnter hook, but now in react-router v4 , it is deprecated. So how can I fetch data right after I click on <Link> component and before the route is changed? Example: it's: at A -> click at <Link> to B -> fetching data for B -> render B not: at A -> click at <Link> to B -> render Route B -> fetching data for B -> rerender B In

Writing Front End for GDB

末鹿安然 提交于 2019-11-28 08:39:53
I want to write a GUI based debugger wrapped over GDB. Because, I dont want the program to stop after watch points or break points. Instead, it should redirect the details like filename, line number, new value and stuffs to a file and continue execution. I am pretty bad at scripting. So, I want some starting point to start developing front end for GDB. As far as I googled, this link http://ftp.gnu.org/old-gnu/Manuals/gdb-5.1.1/html_node/gdb_211.html is not much understandable for a beginner in this activity? Hopefully, I will get help on development in C/C++. For writing a GDB frontend, you

Using API keys in a react app

爱⌒轻易说出口 提交于 2019-11-28 07:23:55
I have a React app that uses two third-party services. The app was started using react-create-app . Both of these services require a API key. One key is supplied via a script tag, like this: <script type="text/javascript" src="https://myapi?key=MY_KEY"> </script> The other API key is used in a request. I store the actual key in a constant and use it to form the request. Like this: const MY_OTHER_KEY = 'MY_OTHER_KEY' let url = `http://myotherapi?key=${MY_OTHER_KEY}&q=${query}` Google's best practice tips on handling API keys says: Do not embed API keys directly in code This brings me to my

good postgresql client for windows? [closed]

亡梦爱人 提交于 2019-11-28 07:06:59
coming back to postgresql after several years of oracle ... what are the state-of-the art postgresql administrative/ddl generating/data inserting frontends on windows? it would be nice if it had integration for postgis as well. it should be standalone or alternatively a plugin for intellij idea thinking back, all the windows programs specific for postgresql i have used were crap, especially PGAdmin. had it become better? I like Postgresql Maestro . I also use their version for MySql. I'm pretty statisfied with their product. Or you can use the free tool PgAdmin. Arthur Thomas do you mean