I'm writing an application and I need to detect arrow keys inside it. C++ has the getch() function. We want to take the input and then add a check on ASCII values.
How can we detect input arrow keys? Thanks
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I have written a Java class RawConsoleInput that uses JNA to call operating system functions of Windows and Unix. It can be used to read the arrow keys, but the character codes are different on Windows and Unix.
Christian d'Heureuse
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How can I read arrow keys with it? – CATboardBETA Aug 03 '21 at 13:30
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@CATboardBETA just read from the console with `RawConsoleInput.read()`, press an arrow key and see what you get. – Christian d'Heureuse Aug 03 '21 at 18:10
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Thanks. This's much easier that trying to inject javascript in and stuff. – CATboardBETA Aug 03 '21 at 18:18
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Actually, I do have an issue. `com.sun.jna.LastErrorException` isn't present in `com.sun.jna:jna` in the maven repo. Is this necessary? – CATboardBETA Aug 03 '21 at 18:27
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Actually, I am getting quite a lot of errors in Intellij. I'm using Java 10. – CATboardBETA Aug 03 '21 at 18:37
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@CATboardBETA You have to add the JNA JAR library (currently jna-5.8.0.jar) to your project. Download from https://github.com/java-native-access/jna – Christian d'Heureuse Aug 04 '21 at 00:00
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This almost works, but after building with maven and running the output jar, I get `NoClassDefFoundError: com/sun/jna/LastErrorException`. There is a similar ClassNotFoundException as well. – CATboardBETA Aug 04 '21 at 00:45
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@CATboardBETA You have to include the JNA JAR file in the class path at runtime. – Christian d'Heureuse Aug 04 '21 at 11:35
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I thought Intellij handled that for you? I have it added as an external library. – CATboardBETA Aug 04 '21 at 12:19