Saad Zahoor wrote:I Want to develop android games. including online server games
That's a good goal, I would love to play your game (hope they are free )
Now, taking things a step at a time, can you write an android app that simply prints "hello world" ? I would suggest beginning with that.
Saad Zahoor wrote:what if we know java 100% . what can we develop . And what is purpose of Xml .. What Xml do .. and For making android app do i need to learn other language other than java ???
There are no limit on what you can do if you know Java. One reason is that is the ideal language to start to learn coding and that in this job continuous learning is so implicit, that also learning other scripting languages can be a necessity.
If you master java for instance you can learn C# in weeks, and PHP in days.
For Android is a bit different, is on the bull eye at the moment, and keep up with all the changes can be really challenging, especially if you need to build up your own portfolio while learning.
Simplifying Android is java built on complex Google APIs. Today there is much more.
XML in android is mainly used to design the so called View/UI
the reasons are different. First of all in this way the view with the business logic they are loosely coupled
A purist of the language could say that I am wrong, because due to the complexity/peculiarities of android and user interactions you need to create
also a proper java class view(programmatically) to specify the cycles, the fragments, the onCreate initialization where to "inflate" the xml Layout..Another essential advantage of using xml is that you can really easy use WYSIWYG editors(What You See Is What You Get), this means you can paint your view without coding, today android is quite
mature that even middle complex app visual design views can be "painted" using a graphical editor adding few attributes manually and see the changes in real time. In this way you can see with your eyes immediately the effect caused by your choices. Since roughly one year this is all the more true with the so called Constrain Layout that allows you to maintain complex layout without establishing a hierarchy between the components.