Android, reference things in R.drawable. using variables?

Question

say I want to dynamically load an image file in R.drawable.* based on the value of a string

Is there a way to do this? It seems like I need to statically refer to anything in R.

Answer 1

Have you declared the id for the image in XML file? If you did, you can use the following method:

Let's say you have picture.png in your res/drawable folder.

In your activity, you can set your image resource in the main.xml file

<ImageView android:id="@+id/imageId" android:src="@drawable/picture"></ImageView>

In FirstActivity

//to retrieve image using id set in xml.
String imageString = "imageId"
int resID = getResources().getIdentifier(imageString , "id", "package.name");
ImageView image = (ImageView) findViewById(resID);

imageString is the dynamic name. After which you can get the identifier of the dynamic resource.

Another method, you can do this:

//to retrieve image in res/drawable and set image in ImageView
String imageName = "picture"
int resID = getResources().getIdentifier(imageName, "drawable", "package.name");
ImageView image;
image.setImageResource(resID );

You will be able to reference your image resource and set your ImageView to it.

Answer 2

int drawableId = getResources().getIdentifier(drawablename, "drawable", getPackageName());
imageview.setImageResource(drawableId);

Try this. This should work.

Answer 3

Class res = R.string.class;
Field field = res.getField("x" + pos);
headerId = field.getInt(null);
header.setText(headerId);

this works with drawables as well, just edit the string. the header part is not required, it's just an example pulled from something I wrote a while ago.