Consider: You can change the alert type, title, text, image, and gauge, as needed. In addition, you can change between requesting a timed or modal alert, as needed (a timed alert stays visible for only a designated period of time; a modal alert requires the user to dismiss it).
Strongly Recommend: 
Use modal alerts only when the user must see and acknowledge the alert. This is the case for alerts that: report serious errors, that warn when data loss might occur, or that ask for confirmation before performing an operation. This advice applies the design consideration, "Minimize Interruptions From MIDP and MIDlets" on page 13.
Strongly Recommend: Do not use tickers in alerts. Tickers distract from the alert message. If you interrupt the user with an alert, the message is important; the user should not be distracted. In addition, alerts are frequently pop-up windows, whereas tickers appear anchored to a screen. The two are incompatible.