如何通过按键关闭J2ME应用程序

本文介绍了如何通过按键关闭J2ME应用程序的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我在Eclipse中有一个带有Nokia SDK插件的J2ME项目，在其中使用了Canvas外观.用户将按一个键退出该应用程序. 但是我真的不知道按键事件后关闭的方式.

I have a J2ME project in Eclipse with Nokia SDK plugin, in which I use a Canvas skin. The users will press a key to quit the application. But I don''t really know the way to close after key pressing event. Help me, please!

推荐答案

一种简单的方法(可能不太优雅，具体取决于您编写Midlet的方式):创建画布时，请执行像这样: 在您的Midlet中，将对Midlet本身的引用传递给Canvas构造函数: One simple way (which may not be very elegant, depending on how you have written your midlet): When you create your canvas, do it something like this: in your Midlet, pass a reference to the Midlet itself to your Canvas constructor: MyCanvas theCanvas = new MyCanvas(this, ...);

在Canvas构造函数中，保存Midlet参考:

in the Canvas constructor, save the Midlet reference:

class MyCanvas extends Canvas implements CommandListener { MyMidlet theMidlet; public MyCanvas(MyMidlet m, ...) { this.theMidlet = m; ... } ... }

然后，当您要从MyCanvas中的keyPressed关闭Midlet时， 只需致电theMidlet.destroyApp() 彼得

Then, when you want to close the midlet from keyPressed in MyCanvas, just call theMidlet.destroyApp() Peter

在您的keyPressed处理程序中，只需调用destroyApp(true). 如果您的Midlet在外部终止，则系统会调用destroyApp，并且应该执行任何清理操作并调用notifyDestroyed(). In your keyPressed handler, just call destroyApp(true). destroyApp is what the system calls if your midlet is terminated externally, and it should do any cleanup required and call notifyDestroyed().

您知道，keyPressedí仅在内部画布类.但是destroyApp和notifyDestroyed是MIDlet类的方法. 如何在我的keyPressed处理程序中调用destroyApp(true)? 请更清楚地向我解释. You know, keyPressed í available just inside the Canvas class. But the destroyApp and notifyDestroyed are methods of MIDlet class. How can we call destroyApp(true) in my keyPressed handler? Please explain me more clearly.