What tools do you need to develop Android software?

Android uses Java as the programming language, which makes the interface and functions change endlessly. Among them, Activity is equivalent to J2ME's MIDlet, an Activity class is responsible for creating a window, an Activity is in foreground mode, and the program running in the background is called Service. These two programs are connected by ServiceConnection and AIDL, so that multiple programs can be run at the same time. If all the pictures of the running activity are replaced by other activities, the activity will be stopped or even terminated by the system.

View is equivalent to the displayable view of J2ME. Programmers can put the UI on the window through the View class and the "xml layout" file. Android 1.5 version can use View to create so-called Widgets. In fact, widgets are just a view, so they can use XML to design layouts. HTC's Android Hero phone contains a large number of widgets. As for ViewGroup, it is an abstract class of various layouts, and there can also be ViewGroup in ViewGroup. The constructor of the view does not need to be called in the activity, but Displayable is necessary. In the activity, the view is obtained from XML through findViewById (), and the display of the view class of Android is largely read from XML. Views are closely related to events and are composed of listeners. Each view can register an event listener. For example, when a view is to handle an event touched by a user, it is necessary to register the view. OnClickListener for Android framework. In addition, the image is equivalent to J2ME bitmap.

Development technology of Android:

1, activity life cycle

Although Android has four components, it is undeniable that Activity is the most commonly used. Therefore, it is necessary to master the life cycle of Android. In fact, the life cycle is to remember when those active methods are called by the system, so that the corresponding logic code can be written into the appropriate methods.

As for the service and broadcast components, we can slow down a little and study them when they are actually used.

2. Interface development technology

Interface development is a basic technology, which is needed by almost all programs. There are three kinds of interface development in Android development:

1) uses xml file layout.

It is the most common application software development technology to use xml to lay out interfaces first and then refer to them in activities. This method is used the most and needs to be learned the most. You need to be familiar with:

A) Five layouts

A deep understanding of the five organization modes of controls is a basic foundation, so that you can flexibly use each layout structure in the actual interface and construct the required interface.

B) public control

There are many controls, at least you need to know what each control does, and you can look up specific parameters and methods when you need to learn.

C) beautiful interface

In many cases, the controls of the system can't meet the requirements, and they need to be beautified by adding backgrounds and changing pictures, and they need to be familiar with how each control can be plum blossom.

With the above knowledge, we can make various interfaces by nesting layout. If you are familiar with the usage of include, you can reduce the repetition of xml and facilitate later modification and maintenance.

2) Dynamic creation using code

Sometimes you need to create some layouts and controls dynamically, so you need to use LayoutInflater to create some dynamic interfaces.

3) Draw your own interface

Commonly used in the game, inherit SurfaceView and draw it yourself.

3. Data storage technology

There are three ways to store data in Android:

1) shared preferred storage

Simple data can be stored in this way, and some basic data can be stored in the form of key-value pairs.

2) File storage

Store data in the form of a file, which can be the storage of the mobile phone itself or the SD card. The data format of the file is defined by itself.

3)SQLite database storage

Operating with standard SQL statements is the first choice for complex data.

4, network programming

There are not many Android programs that don't need to be connected to the internet now. So network programming is also necessary. General companies will have their own network architecture, but they should be familiar with the basic network.

1)HTTP networking

Using Http networking +Json data format is the first choice for many clients now.

2) Socket network

As for the connection methods such as Bluetooth, you can learn when the project needs it.

For the system functions of mobile phones, such as making phone calls, sending text messages, reading system parameters, etc. You can study on demand without any trouble.

Secondly, mobile phone software is related.

Android development is different from ordinary computer software development, and it needs to know the operating habits of mobile phones, such as small screen, limited memory and limited battery. Therefore, it should be considered as much as possible in the actual development and design.