devcap.java

J2ME MIDP 2.0 无线设备编程的一些源码

//DevCap.java file
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;

public class DevCap extends MIDlet implements CommandListener
{
    private Command exitCommand;
    private Canvas canvas;
    public DevCap()
    {
        exitCommand =new Command("Exit",Command.EXIT,1);
        canvas = new Canvas(){public void paint(Graphics g){}};
        canvas.addCommand(exitCommand);
        canvas.setCommandListener(this);
    }
    
    protected void startApp(  ) throws MIDletStateChangeException
    {
        devCapability(Display.getDisplay(this),canvas);
        devCapability2(Display.getDisplay(this));
        Display.getDisplay(this).setCurrent(canvas);
    }
    
    protected void pauseApp(  )
    {
    }

    protected void destroyApp( boolean p1 )
    {
    }

    public void commandAction(Command c,Displayable d)
    {
        if (c ==exitCommand)
        {
            destroyApp(false);
            notifyDestroyed();
        }
    }
    public static void devCapability(Display d, Canvas c)
    {//在支持MIDP v1.0、v2.0的设备中运行
        System.out.println("支持彩色 " + d.isColor());
        System.out.println("颜色数量 " + d.numColors());
        System.out.println("正常屏幕宽度 " + c.getWidth());
        System.out.println("正常屏幕高度 " + c.getHeight());
        System.out.println("支持指针设备 " + c.hasPointerEvents());
        System.out.println("支持指针设备拖放 " + c.hasPointerMotionEvents());
        System.out.println("支持按键重复事件 " + c.hasRepeatEvents());
    }
    
    public static void devCapability2(Display d)
    {//只能在支持MIDP v2.0的设备中运行
        System.out.println("AlphaBlend支持程度 " + d.numAlphaLevels()); //小于2表示不支持
        System.out.println("List内图标 最佳宽度" + d.getBestImageWidth(d.LIST_ELEMENT));
        System.out.println("List内图标 最佳高度" + d.getBestImageHeight(d.LIST_ELEMENT));
        System.out.println("ALERT内图标 最佳宽度" + d.getBestImageWidth(d.ALERT));
        System.out.println("ALERT内图标 最佳高度" + d.getBestImageHeight(d.ALERT));
        System.out.println("ChoiceGroup内图标 最佳宽度" + d.getBestImageWidth(d.CHOICE_GROUP_ELEMENT));
        System.out.println("ChoiceGroup内图标 最佳高度" + d.getBestImageHeight(d.CHOICE_GROUP_ELEMENT));
    }
}