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jvx:client:gui:temporary_values [2019/08/26 09:16] admin |
jvx:client:gui:temporary_values [2021/02/01 12:47] (current) admin |
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| ~~NOTRANS~~ | ~~NOTRANS~~ | ||
| - | ~~Title: Temporary values~~ | + | ~~Title: Temporary Values~~ |
| - | Sometimes it's important to store/cache temporary information. It's no problem to create or use a variable to save such information. This is also the recommended solution because it makes the code readable and references can be found. But sometimes it's good to have an alternative to clean code because sometimes you want to add information to existing objects, quick and easy. | + | Sometimes it's important to store/cache temporary information. It's no problem to create or use a variable to save such information. This is also the recommended solution because it makes the code readable and references can be found. However, sometimes it's good to have an alternative to clean code because sometimes you want to add information to existing objects quickly and easily. |
| - | As example, you could open a work-screen and add additional metadata like readonly or allowed users. To solve this problem, you could save the screen in a HashMap with metadata as values. This information should be saved in the Application because the screen has access to the application. This makes things a little bit complicated. | + | === Instance Values === |
| - | To make everything easier, every UI resource (e.g. a component) has the methods: | + | As an example, you could open a work-screen and add additional metadata like read-only or allowed users. To solve this problem, you could save the screen in a HashMap with metadata as values. This information should be saved in the application because the screen has access to the application. This makes things a little bit complicated. |
| + | |||
| + | To make everything easier, every UI resource (e.g., a component) has the methods: | ||
| <code java> | <code java> | ||
| Line 17: | Line 19: | ||
| </code> | </code> | ||
| - | So it's super easy to add temporary information to any UI resource. We recommend to use constants as object names, to find references easily. If you use hardcoded strings, it will be hard to find the usage in your whole application. | + | So, it's super easy to add temporary information to any UI resource. We recommend to use constants as object names in order to find references easily. If you use hardcoded strings, it will be hard to find the usage in your whole application. |
| Here's a short example: | Here's a short example: | ||
| Line 29: | Line 31: | ||
| } | } | ||
| </code> | </code> | ||
| - | We save a simple **"state"** for the screen, directly in the screen instance. | + | We save a simple **"state"** for the screen directly in the screen instance. |
| - | It's also possible to use the launcher or application, e.g. | + | It's also possible to use the launcher or application, e.g., |
| <code java> | <code java> | ||
| + | @Override | ||
| protected void afterLogin() | protected void afterLogin() | ||
| { | { | ||
| Line 41: | Line 44: | ||
| } | } | ||
| </code> | </code> | ||
| - | We save the **"application mode"** in the launcher and this information is available in every screen or any other class which has access to the launcher. | + | We save the **"application mode"** in the launcher and this information is available in every screen or any other class which has access to the launcher. It's not possible to add variables to the launcher or to change the class directly, so it's a good alternative to use custom objects to add metadata and to avoid HashMap for simple caching. |
| + | |||
| + | ==== Global Values ==== | ||
| + | |||
| + | We have another alternative for the above instance values. It's also possible to use our [[jvx:common:util:classes#the_object_cache|ObjectCache]], e.g., | ||
| + | |||
| + | <code java> | ||
| + | //available for 1 minute | ||
| + | ObjectCache.put(IConstants.APPMODE, AppMode.AUTHENTICATED, 60000); | ||
| + | </code> | ||
| + | The ObjectCache is a static cache and can be used to use values without application context. It's also possible to use an **ObjectCacheInstance** which isn't static. | ||