Conditional pop window

Question

So I'm still very new to Java and Android programming. The scenario here is that I have created an app which scores the users progress based on how many of their goals they would have achieved at the end of the week. At the end of the scoring process they accumulate points. Based on their accumulated score over several weeks they can acquire trophies. Once they are finish scoring themselves they are taken to an result activity which changes its background image based on the score they achieved for the particular week. On this very same result activity I would to use a popup window to inform them based on their accumulated points when they have one a trophy. Most of the sample code i have seen use a button to open the pop up. But I would like my to open as soon as the result activity starts and based on whether they met the points for each of the trophies. I tried something myself but as soon as i open the activity it crashed. Please help?!