How do I get the resource id of an image if I know its name (in Android)?
This question is related to
android
android-image
android-resources
Example for a public system resource:
// this will get id for android.R.drawable.ic_dialog_alert
int id = Resources.getSystem().getIdentifier("ic_dialog_alert", "drawable", "android");
Another way is to refer the documentation for android.R.drawable class.
You can also try this:
try {
Class res = R.drawable.class;
Field field = res.getField("drawableName");
int drawableId = field.getInt(null);
}
catch (Exception e) {
Log.e("MyTag", "Failure to get drawable id.", e);
}
I have copied this source codes from below URL. Based on tests done in this page, it is 5 times faster than getIdentifier(). I also found it more handy and easy to use. Hope it helps you as well.
One other scenario which I encountered.
String imageName ="Hello" and then when it is passed into getIdentifier function as first argument, it will pass the name with string null termination and will always return zero. Pass this imageName.substring(0, imageName.length()-1)
With something like this:
String mDrawableName = "myappicon";
int resID = getResources().getIdentifier(mDrawableName , "drawable", getPackageName());
You can use this function to get a Resource ID:
public static int getResourseId(Context context, String pVariableName, String pResourcename, String pPackageName) throws RuntimeException {
try {
return context.getResources().getIdentifier(pVariableName, pResourcename, pPackageName);
} catch (Exception e) {
throw new RuntimeException("Error getting Resource ID.", e)
}
}
So if you want to get a Drawable Resource ID, you can call the method like this:
getResourseId(MyActivity.this, "myIcon", "drawable", getPackageName());
(or from a fragment):
getResourseId(getActivity(), "myIcon", "drawable", getActivity().getPackageName());
For a String Resource ID you can call it like this:
getResourseId(getActivity(), "myAppName", "string", getActivity().getPackageName());
etc...
Careful: It throws a RuntimeException if it fails to find the Resource ID. Be sure to recover properly in production.
Source: Stackoverflow.com