How does the color value of the four grayscale?
Private final static int white_color = 0x00FFFFFF;
PRIVATE FINAL static int Light_gray = 0x00888888;
PRIVATE FINAL Static Int Dark_gray = 0x00444444;
PRIVATE FINAL Static Int Black_color = 0x00000000;
How does J2ME adapt to design more modular and radiation? J2ME is designed to be more modular and removable. J2ME built a 3-layer software on the original operating system to achieve modularity and removal:
v JVM layer: This layer is based on the host operating system, which implements JVM according to the configuration of a J2ME. v Configuration layer: This layer is low for user visibility, but it is very important to the framework. It defines the minimum set of functions of Java virtual machines and the minimum collection of Java class libraries in the "Level" market. In a sense, the configuration layer defines the "minimum blend mother" of the developer's Java features and class libraries that can be used on all devices. v Frame layer: This layer is the most common for users and application providers. It defines the smallest set of Java virtual machines and the minimum collection of Java class libraries in the "vertical" market. The frame is implemented based on a specific configuration layer. As long as the device supports the same framework layer, applications developed for a particular framework layer can be ported to other devices. A device can support multiple frame layers.
When I run a compiled program, the emulator has an error warning that I am in an emulator when running the compiled program: java.lang.noclassdeffounderror. What is going on? There are two possibilities: First, pay attention to the Package path, for example, for Package Com.mot.j2me.mIdlets.test, your class must be in the following path:% classpath% / COM / MOT / J2ME / MIDLETS / TEST / . Second, pay attention to case, for example, Test.class and Test.class are two different classes.
Issues When I am loaded into a PNG graphic file, I am running when I am loading the PNG graphic file, the Exception is running: Image cannot be loaded or decoded. However, the PNG file is normal under the viewing software. How should I display correctly? First create a PNG file with graphics processing software, then convert it into byte arrays, and content should be one or one. The color of PNG should be 2Bit or 1bit because the hardware device only supports 4 grayscale display. The statement of the creation map should be the following format: image.createImage (byte [] imagedata, int imageoffset, int imagelength), where imagedata's format is: {(byte) 0x89, (byte) 0x50, (byte) 0x4e, (Byte) 0x4e, (Byte) 0x4e 0x47, (Byte) 0x0d, ....
I have (no) C (Java) programming experience, how should I open because Java is a purely object-oriented language, so if you don't have C or Java experience, we recommend that you start J2ME development, most Good first understand some basic concepts and applications for object-oriented development. You can then refer to the following steps as the beginning: 1> a PC. It is recommended to minimize PII300, 128MB memory, 4GB hard drive, 56K Internet connection. WINDOWS operating system. 2> JDK1.2.2 or more, JDK1.3 can be downloaded from http://java.sun.com/j2se/1.3/download, about 30MB. 3> Download Motorola's J2ME software development package, please visit https://commerce.motorola.com/idenonline/ideveloper/index.cfm, after register, click Tools & Resources link, then download the MOSDK Windows version. After the installation is complete, you can refer to the sample program of Motosdk and run in the simulator. What does J2ME mean? J2ME is an abbreviation for Java 2 Micro Edition. It is a technique that Sun is launched by Sun In order to apply Java to mobile communication devices, embedded devices, or consumer electrical appliances. (Generally in personal computer is J2SE? Java 2 Standard Edition; J2EE? Java 2 Enterprise Edition J2EE? Java 2 Enterprise Edition) J2ME includes virtual machines, configured and frame definitions for devices (Configuration & Framework definitions for devices). Profile, etc. Interested friends can go to the SUN website http://java.sun.com/j2me or refer to the J2ME introduction under the documentation of this site.
What is the life cycle of the MIDlet?
Discussion group KVM: http://forum.java.sun.com/list/discuss.sun.k.virtual.machine.kvm java Embedded Server: http://forum.java.sun.com/list/discuss.sun .javaserver.products Embedded Java: http://forum.java.sun.com/list/discuss.sun.Embeddedjava Personal Java: http://forum.java.sun.com/list/discuss.sun.Personaljava
Java TV http://forum.java.sun.com/list/discuss.sun.java.tv
Java card http://forum.java.sun.com/list/discuss.sun.java.card
