Android: drawable id change after resources modify
I have an android application that use a gallery component to choose an icon and assign it to a button.
The icon set is located inres/drawable
folder and is accessed in the gallery with the typical adapter of the guide:
private Integer开发者_运维技巧[] Imgid = {
R.drawable.icon_home,
R.drawable.icon_home2,
...
}
After an icon choosing, i stored the settings in a db with id of the button and of the drawable.
All works done, but i've noticed that if i'll want to add or modify my icon set or resources in general of my application, ids of old resource could change, so the preferences in the db refers to wrong icon. Is there a way to force the old id of R class so they didn't change in the future? Or is there another way to manage the item of the component galley with another attribute than id? (maybe string name and reflection?)Thanks in advance
You can store the name of the drawable in the database if you don't plan to change that. getResourceEntryName
returns the name from the resource id:
Resources resources = getResources();
String name = resources.getResourceEntryName(R.drawable.icon);
And you can get back the resource id from the name with getIdentifier
:
int resId = resources.getIdentifier(name, "drawable", "your.package.name");
You can't use static int for resource identifier, however you should look at two methods od Resources
class:
getIdentifier()
getresourceName()
You shouldn’t rely on the actual values of the R.drawable.*
attributes.
Create your own ids instead (for example 1 correspond to R.drawable.icon_home
and 2 correspond to R.drawable.icon_home2
)
Edit:
String name and reflection should work too, but it’s probably a little overkill you have only a few icons.
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