Chapter 4: Going Native
In This Chapter
Connecting C code to Java code
Creating an Android app with native code
Sometimes, you have to get your hands dirty. You have to pop the hood and figure out why smoke comes out of your car. You have to bake a cake for that special friend who’s allergic to the ingredients in store-bought cakes. Or, in order to build the perfect mobile app, you must bypass Android’s comfortable Java coating and dig deep to find your true inner geek. You must create part of an app in the primitive, nuts-and-bolts, down-and-dirty language called C.
Book II, Chapter 2 explains how Java puts a virtual machine between your processor’s hardware and a running application. Java programs don’t turn directly into sets of instructions that your processor can then run. Instead, your processor runs a set of instructions, or a virtual machine. (Your Android device runs the Dalvik Virtual Machine; your laptop computer runs the Java Virtual Machine.) The virtual machine interprets a Java program’s instructions and carries out these instructions on your processor’s behalf.
Anyway, this added layer of software (between the Java instructions and your processor’s circuits) has both benefits and drawbacks. Isolation from the hardware enhances portability and security. But the added ...
