adding flash lights:
dialog is small window on the screen. when dialog is executed the activity losses its focus and dialog gets total control of app.
android.app. dialog package
date picker dialog
time picker dialog
alert dialog: it is a small window. it contains 0,1,2 or 3 buttons combination.It contains max 3 buttons like +ve ,-ve, neutral buttons.
its an extension of alert dialog class that can display progress animation in the form of spinning wheel.