state

问题 Say I have React component that renders a set of buttons,I store the information for the buttons in an object, with a label and a method to run when they are attached. The buttons do not need to react to any changes, and will never change themselves. Is it a bad practice to store the information for these buttons in the state? These are the current solutions I have come up with so far. 1. Storing Buttons in State class Header extends Component { constructor() { super(); this.state = { buttons

问题 I have a few HttpWebRequests and HttpWebResponses chained together, also using CookieContainer. The code simulates a user going through three different 'I agree' pages which set the cookie info, logging in with username and password on a fourth, and doing a POST (search) on the fifth returning the response as a string. Is there a way I can maintain the HttpWebRequest object as 'logged in' to avoid going through those steps each time any user performs a search? Can I set it up as static, and

问题 I have a few HttpWebRequests and HttpWebResponses chained together, also using CookieContainer. The code simulates a user going through three different 'I agree' pages which set the cookie info, logging in with username and password on a fourth, and doing a POST (search) on the fifth returning the response as a string. Is there a way I can maintain the HttpWebRequest object as 'logged in' to avoid going through those steps each time any user performs a search? Can I set it up as static, and

问题 I'm working in a new codebase. Normally, I would set up state like this in a React component: class App extends React.Component { constructor() { super(); this.state={ foo: 'bar' } } .... In this new codebase, I'm seeing a lot of this: class App extends React.Component { state={ foo: 'bar' } .... Is there an advantage to doing it this way? They seem to only do it when state doesn't need to be altered. I always thought of state as being something React handled. Is this an ok thing to do? 回答1:

问题 I want to add new key value to array ınto state? I tell you what I want to do below. How can I do that? 1. Start state in consruture method `this.state = { files: [] }' After I doing set state with active files this.setState({files: activeFiles}) Screen my state { files: [ { key1: val1, key2: val2, key3: val3 }, { key1: val1, key2: val2, key3: val3 }, { key1: val1, key2: val2, key3: val3 } ] } How to add new key value for each file? The state I want { files: [ { key1: val1, key2: val2, key3:

问题 In my class view phone cam will be opened and programme shows the bitmap after user take photo from phone cam but at the same time the user rotates the screen to "landscape" bitmap will disappear and activity's oncreate() will load again and then camera will be opened again. I didnt know save bitmap with onRetainNonConfigurationInstance() or onSaveInstanceState(). The question is this how can I save the bitmap(taken from phone cam) before user rotates the phone so that even if phone is

问题 Is there any way in Oracle to determine whether a package has state or is stateless? I'm not aware of any view in the data dictionary that contains that information. The "ORA-04068: existing state of packages string has been discarded" error is rather annoying. It can be eliminated by removing package variables from the package. 11g introduced the feature that a package with variables that are all compile-time constants will be treated as stateless. I could have two sessions and compile the

问题 How do I find out if the keyboard is up? I have a UISearchbar instance which becomes the first responder. When the keyboard appears a notification is sent out as part of the API, however I don't want to respond to this right away. I could record this in a boolean state, but that seems clunky. I'd like to know if there is a "getter" some where I can call to find out. 回答1: This is how I do it: KeyboardStateListener.h @interface KeyboardStateListener : NSObject { BOOL _isVisible; } +

问题 As usual in android, each time the screen is flipped to portrait/landscape mode an Activity runs through life-cycle from onSaveInstanceState to onDestroy and then is recreated. In my Activity there's a ButtonText which can be changed by the user. It's reseted to the initial state, but I have to save the last state somehow. How can I achieve that, will I have to override onSaveInstanceState? Can someone show an example? 回答1: Step #1: Call getText().toString() on the Button to get the caption.

问题 As usual in android, each time the screen is flipped to portrait/landscape mode an Activity runs through life-cycle from onSaveInstanceState to onDestroy and then is recreated. In my Activity there's a ButtonText which can be changed by the user. It's reseted to the initial state, but I have to save the last state somehow. How can I achieve that, will I have to override onSaveInstanceState? Can someone show an example? 回答1: Step #1: Call getText().toString() on the Button to get the caption.