The Emulator

The Emulator

Running your application on a physical device versus an emulated device is pretty much the same thing. That is because the emulator is an actual code emulator, meaning it runs the same code base as the actual device, all the way down to the machine layer.

A simulator and an emulator sound very similar, but are fundamentally different. To emulate means to imitate the machine executing the binary code. So, an emulator is sort of like a virtual machine. A simulator merely simulates the behavior of the code at a higher level. Android SDK ships with a true emulator, based on QEMU.

To use the emulator, we’ll have to create an Android Virtual Device (AVD). The easiest way to do that is to start the android tool via Eclipse.

To create a new AVD, start the tool called Android SDK and AVD Manager (see Fig-   icon or via theure 3-3). You can start this tool from Eclipse by clicking on the command line by starting the tool called android, which is located in your SDK/tools directory. From within the Android SDK and AVD Manager window, choosing “New…” pops up a Create New AVD dialog window (see Figure 3-4). In this dialog, you specify the parameters for your new AVD. The name can be any name you choose. The target designates which version of Android you want installed on this particular AVD. The list of possible targets is based on platforms and add-ons that you have installed into your SDK. If you don’t have any targets, go back to the Android SDK and AVD Manager window and choose the “Available packages” tab to install at least one platform, for example, Android 2.3 - API level 9. Each AVD can have an SD card. You can just specify a number here for your built-in card, in megabytes. The skin is the look and feel of your device as well as its form factor. The Hardware option lets you fine-tune what this AVD does and doesn’t support.