Q：AppInventor2 文本和数字如何转换？ A：先来一个文本转数字的情况： 定义一个变量赋初值 数字0，然后将文本设置给它，事实证明这时它自动变成了文本类型，而不再是数字。因此此方案行不通。 最彻底的方案： [hide] 直...

屏幕数量：3个，代码块200左右，游戏完成度很高，可玩性非常好，有很好的学习参考价值。 apk可以安装试玩。

屏幕数量：1个，代码块100左右，非常简易的地图游戏，通过方向按钮控制小人的方向行走，遇到障碍物则停止。可玩性非常好，有很好的学习参考价值。 apk可以安装试玩。

软件自带的下拉框，太简单了，想请问下，有没有相应的扩展，可以方便的修改下拉框的颜色，字体，外形这些？

16进制，取高8位，按位与后，如何向右位移8位呢？？位移的组件是什么？

Runtime Error java.lang.NoSuchMethodError: No virtual method append(Ljava/ lang/String;)Ljava/lang/ AbstractStringBuilder; in class Ljava/ lang/StringBuffer; or its super classes (declaration of 'java.lang. StringBuffer' appears in /apex/com.android.art/ javalib/core-oj.jar) 原因：过...

... found out how to do this on the Android emulator itself (Menu, "Settings" App - not the settings of the emulator outside). All you need to do is: open settings app -> Language & Input -> Go to the "Keyboard & Input Methods -> click Default This will bring up a Dialog in which case ...

I'm developing an app on Heroku with a Postgresql backend. Periodically, I get this error message when trying to access the database, both from the CLI and from loading a page on the server: ...

...ity when started in landscape, see developer.android.com/reference/android/app/… – Bondax Apr 9 '15 at 8:59 ...

What is an AppDomain ? What are the benefits of AppDomains or why Microsoft brought the concept of AppDomains, what was the problem without AppDomains? ...