黑莓 - 如何获取后台应用程序进程 ID

Question

在我的黑莓模拟器中，我正在后台运行两个应用程序，现在我想检索哪些是在后台运行的应用程序。我不知道该怎么做。是否可以显示哪些是在后台运行的应用程序。

Answer 1

列出并切换可见应用

• 要列出所有可见的应用程序，请使用 ApplicationManager.getVisibleApplications()
• 要带一些应用程序前台使用 ApplicationManager.requestForeground(processId)

alt text http://img195.imageshack.us/img195/7003/applist.png link text http://img32.imageshack.us/img32/9273/applistmenu.png

代码:

class Scr extends MainScreen {

    ApplicationDescriptor[] mAppDes;

    public Scr() {
        listApplications();
    }

    void listApplications() {
        ApplicationManager appMan = 
            ApplicationManager.getApplicationManager();
        mAppDes = appMan.getVisibleApplications();
        add(new LabelField("Visible Applications:"));
        for (int i = 0; i < mAppDes.length; i++) {
            boolean isFG = appMan.getProcessId(mAppDes[i]) == appMan
                    .getForegroundProcessId();
            String text = (isFG ? "[F]:" : "[B]") + mAppDes[i].getName();
            add(new LabelField(text));
        }
    }

    protected void makeMenu(Menu menu, int instance) {
        super.makeMenu(menu, instance);
        menu.add(refreshApps);
        makeAppMenuItems(menu);
    }

    MenuItem refreshApps = new MenuItem("Refresh", 0, 0) {
        public void run() {
            deleteAll();
            listApplications();
        }
    };

    class AppMenuItem extends MenuItem {
        ApplicationDescriptor mAppDes;
        public AppMenuItem(ApplicationDescriptor appDes) {
            super(appDes.getName(), 100000, 100000);
            mAppDes = appDes;
        }
        public void run() {
            ApplicationManager appMan = ApplicationManager
                    .getApplicationManager();
            int processId = appMan.getProcessId(mAppDes);
            appMan.requestForeground(processId);
        }
    }

    void makeAppMenuItems(Menu menu) {
        for (int i = 0, cnt = mAppDes.length; i < cnt; i++)
            menu.add(new AppMenuItem(mAppDes[i]));
    }
}