Foxit PDF SDK 5.3

How to modify or add additional functionality/methods to the Android C API demo?

Follow the steps to add new functionality to your Android C API demo for Foxit PDF SDK:

  1. Go to “samples\ViewerDemo\jni” and review how the implementation on how some of the API are already done. Tip: Look for functions that have similar parameters and use it has your template for writing your own.
  2. Create a new .cpp and .h file that includes the method you need. For guidance, see 

    For example for the cpp content,

  3. JNIEXPORT jint JNICALL Java_com_foxit_gsdk_pdf_MyNewSomething 
    (JNIEnv *env, jobject jpdfObj, jlong parameter1, jint parameter2, jobject parameterEtc) 
    // Wrap job here. Means error handling and how you want the function to work. return FSPDF_SOMETHING(parameter1); 
    // For example for the .h content, 
    JNIEXPORT jint JNICALL Java_com_foxit_gsdk_pdf_MyNewSomething 
    (JNIEnv *, jobject, jlong, jint, jobject);
  4. Open samples\ViewerDemo\jni\arm_mk\jni\Android.mkAnd add your new source file to the define

    For example, LOCAL_SRC_FILES :=\

    For example, “$(SRC_PATH)/com_foxit_gsdk_pdf_MyNewSomethingSource.cpp \

  5. Add the same define from step c to samples\ViewerDemo\jni\x86_mk\jni\
  6. Create a Java file at “samples\ViewerDemo\pdf_src\com\foxit\gsdk\pdf” and define your interface.
  7. Open a command prompt/Cygwin and navigate to “samples\ViewerDemo\jni” and run the command ndk-build –b Note: Please see “docs\FoxitPDFSDK4_1_DeveloperGuide.pdf” if you are having problems running this command.
  8. The new interface should now be available to use.

Note: This article refers to a deprecated version of a Foxit Product. If you are still using Foxit PDF SDK 5.3 or older, please refer to your download package documents for Developer Guide and API Reference.

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Updated on April 5, 2017

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