创建客制化的Camera对象步骤

• Detect and Access Camera - Create code to check for the existence of cameras and request access.
• Create a Preview Class - Create a camera preview class that extends SurfaceView and implements theSurfaceHolder interface. This class previews the live images from the camera.
• Build a Preview Layout - Once you have the camera preview class, create a view layout that incorporates the preview and the user interface controls you want.
• Setup Listeners for Capture - Connect listeners for your interface controls to start image or video capture in response to user actions, such as pressing a button.
• Capture and Save Files - Setup the code for capturing pictures or videos and saving the output.
• Release the Camera - After using the camera, your application must properly release it for use by other applications.

http://developer.android.com/guide/topics/media/camera.html#intents