Question

I want to have a class “Utils”, that will have several methods used all over my code. For example, I have a top bar with a textview and two ImageButtons that must display different texts and icons on different activities.

I find myself writing stuff like this on every activity:

(TextView) topBarText = (TextView) findViewById(R.id.topBarText);
topBarText.setText(R.id.mytextForThisView);

I’d like to findViewById once in my whole app, and call a method setupTopBar(String text, R.id.iconForImageButton1, R.id.iconForImageButton2), or even pass the current Activity’s id and let the method figure out what to show in the text and images.

I created the class Util, but it doesn’t extend Activity. The problem is that if it doesn’t, findViewById isn’t accessible, so I can’t use it.

What’s the pattern to do something like this in Android?

Answer 1

Your helper methods should look like

public static void setTopBarText(Activity act, int textId){
    (TextView) topBarText = (TextView)act.findViewById(R.id.topBarText);
    topBarText.setText(textId);
}

Then you can do a static import from Activity and call

setTopBarText(this, R.id.mytextForThisView);