java - 如何在 BlackBerry 中关闭全局对话框并显示另一个对话框？

Question

当中间时间大于等于4分钟时，需要显示 消息对话框。如果空闲时间大于或等于5分钟， 我需要关闭第一个对话框并推送另一个应该自动出现的对话框 5 秒后关闭。

这是我到目前为止所拥有的:

public static RealtimeClockListener clockListenerTest = new RealtimeClockListener() {
                public void clockUpdated() {
                        int _4Minutes = 60 * 4;
                        int _5Minutes = 60 * 5;
                        Dialog dialog4Minutes = new Dialog("Stay Logged In?", new String[] {"SI", "NO"}, new int[]{1,2}, 2, null);
                        dialog4Minutes.setDialogClosedListener(new DialogClosedListener() {
                                public void dialogClosed(Dialog dialog, int choice) {
                                    //TODO
                                }
                        });
                        Dialog dialog5Minutes = new Dialog("You will be disconnected", new String[] {"OK"}, new int[]{1}, 1, null);
                        dialog5Minutes.setDialogClosedListener(new DialogClosedListener() {
                                public void dialogClosed(Dialog dialog, int choice) {
                                    //TODO
                                }
                        });
                        synchronized (UiApplication.getEventLock()) {
                                UiEngine ui = Ui.getUiEngine();
                                if(DeviceInfo.getIdleTime()>=_4Minutes && DeviceInfo.getIdleTime() < _5Minutes){
                                        ui.pushGlobalScreen(dialog4Minutes, 1,UiEngine.GLOBAL_QUEUE);
                                }else if(DeviceInfo.getIdleTime()>=_5Minutes){
                                        dialog4Minutes.close();
                                        ui.pushGlobalScreen(dialog5Minutes, 1,UiEngine.GLOBAL_QUEUE);
                                }
                        }
                }
        };

我的代码的问题是第一个对话框永远不会在 else 子句中关闭，并且 在手动关闭第一个对话框之前，不会显示第二个对话框。

如何使 else 子句中的代码正常工作？ 5秒后我应该如何关闭第二个对话框？我正在考虑为此设计一个计时器 但我不知道这是否是最好的方法。

提前致谢!

Answer 1

我认为您的代码中有一个简单的编码错误，这可能会导致您的问题。每次你通过clockUpdated()，你都会创建一个新的对话框4Minutes。因此，当您使用dialog4Minutes.close() 关闭它时，您实际上是在关闭刚刚创建的窗口，而不是正在显示的窗口。这是一些示例(未编译，未测试)替换代码，指示我将如何执行此操作:

public static RealtimeClockListener clockListenerTest = new RealtimeClockListener() {
    int _4Minutes = 60 * 4;
    int _5Minutes = 60 * 5;
    Dialog dialog4Minutes = null;
    Dialog dialog5Minutes = null;
    public void clockUpdated() {
        synchronized (UiApplication.getEventLock()) {
            UiEngine ui = Ui.getUiEngine();
            if ( DeviceInfo.getIdleTime() < _4Minutes ){
                // Shouldn't be needed - this is just for safety
                if ( dialog4Minutes != null ) {
                    dialog4Minutes.close();
                    dialog4Minutes = null;
                }
            }
            if ( DeviceInfo.getIdleTime() < _5Minutes ){
                // Shouldn't be needed - this is just for safety
                if ( dialog5Minutes != null ) {
                    dialog5Minutes.close();
                    dialog5Minutes = null;
                }
            }
            if ( DeviceInfo.getIdleTime() >= _4Minutes && DeviceInfo.getIdleTime() < _5Minutes ) {
                if ( dialog4Minutes == null ) {
                    // 4 minute Dialog has not been pushed yet
                    dialog4Minutes = new Dialog("Stay Logged In?", new String[] {"SI", "NO"}, new int[]{1,2}, 2, null);
                    ui.pushGlobalScreen(dialog4Minutes, 1,UiEngine.GLOBAL_QUEUE);
                }
            } else if ( DeviceInfo.getIdleTime()>=_5Minutes ) {
                if ( dialog5Minutes == null ) {
                    // 5 minute Dialog has not been pushed yet
                    dialog5Minutes = new Dialog("You will be disconnected", new String[] {"OK"}, new int[]{1}, 1, null);
                    ui.pushGlobalScreen(dialog5Minutes, 1,UiEngine.GLOBAL_QUEUE);
                    if ( dialog4Minutes != null ) {
                        dialog4Minutes.close();
                        dialog4Minutes = null;
                    }
                }
            }
        }
    }
};

我不确定是否需要“同步(UiApplication.getEventLock())”，因为我认为clockUpdated在事件线程上运行，但在这段代码中，它不会造成伤害。

关于你的另一个问题，关于如何处理 5 秒后关闭，请查看 Timer 类。如果用户确实确认了该对话框，您将必须编写 setDialogClosedListener 代码(我在示例中忽略了它)才能采取行动。