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How do I create a basic UIButton programmatically?
...height: 500)
myButton.addTarget(self, action: #selector(pressedAction(_:)), for: .touchUpInside)
self.view.addSubview( myButton)
func pressedAction(_ sender: UIButton) {
// do your stuff here
print("you clicked on button \(sender.tag)")
}
SwiftUI
for example you get the step by ...
Rerender view on browser resize with React
...lobals window */
import React, { useState, useEffect } from 'react'
import _debounce from 'lodash.debounce'
const Example = () => {
const [width, setWidth] = useState(window.innerWidth)
useEffect(() => {
const handleResize = _debounce(() => setWidth(window.innerWidth), 100)
w...
Android emulator shows nothing except black screen and adb devices shows “device offline”
...tor comes up on the screen. But even after waiting for as long as 2-3 hrs, all it shows is a black screen. Not even the android home screen or the android logo. Just a black screen. And while initially "adb devices" shows the emulator as offline.after 2-3 minutes the list of attached devices becomes...
How to emulate C array initialization “int arr[] = { e1, e2, e3, … }” behaviour with std::array?
...s question is about not having to specify the number of elements and still allow nested types to be directly initialized.)
This question discusses the uses left for a C array like int arr[20]; . On his answer , @James Kanze shows one of the last strongholds of C arrays, it's unique initializat...
Loading local JSON file
...
Are you really allowed to access a local file?
– maasha
Nov 21 '12 at 19:21
4
...
fetch in git doesn't get all branches
... manual, and it seems dead straight easy. Strangely it's not working, and all the posts I've found suggest I'm doing the right thing. So I'll subject myself to the lambasting, because there must be something obviously wrong with this:
...
How do I edit an existing tag message in git?
...;tag-name> [commit]
Whole story:
Building on Sungram's answer (originally proposed as an edit):
1. Accepted answer
This is an improvement over Andy and Eric Hu's answers.
Their answers will create a new tag object that references the old tag object and both are going to have the same name. ...
filter for complete cases in data.frame using dplyr (case-wise deletion)
...data.frame for complete cases using dplyr? complete.cases with a list of all variables works, of course. But that is a) verbose when there are a lot of variables and b) impossible when the variable names are not known (e.g. in a function that processes any data.frame).
...
Pure virtual function with implementation
...e type can still define an implementation. A derived class can explicitly call the base class implementation (if access permissions allow it) by using a fully-scoped name (by calling A::f() in your example - if A::f() were public or protected). Something like:
class B : public A {
virtual voi...
Can table columns with a Foreign Key be NULL?
...d Mar 2 '10 at 21:37
Daniel VassalloDaniel Vassallo
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