android C程序截屏求助！！！！！！！！！！！
C程序编译可通过，项目运行也可以，但是在执行到调用C程序方法时报错，求助呢，找不到原因了上代码帮忙看看！！！
java调C：
package com.android.ScreenCap;
import java.io.File;
import android.os.Environment;
public class ScreenCapNative {
static {
System.loadLibrary("screencapjni");
};
private native static void nativeCaptureScreen(String file);
public static String startCaptureScreen() {
String file_name = getUniqueFileName();
if (file_name != null) {
nativeCaptureScreen(file_name);//这里开始调用C程序时就报错了
}
return file_name;
}
private static String getUniqueFileName() {
File file = null;
if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
file = createUniqueFile(Environment.getExternalStorageDirectory(),
"ScreenCap.jpg");
}
return (file != null) ? file.getAbsolutePath() : null;
}
private static File createUniqueFile(File directory, String filename) {
File file = new File(directory, filename);
if (!file.exists()) {
return file;
}
// Get the extension of the file, if any.
int index = filename.lastIndexOf('.');
String format;
if (index != -1) {
String name = filename.substring(0, index);
String extension = filename.substring(index);
format = name + "-%d" + extension;
}
else {
format = filename + "-%d.jpg";
}
for (int i = 2; i < Integer.MAX_VALUE; i++) {
file = new File(directory, String.format(format, i));
if (!file.exists()) {
return file;
}
}
return null;
}
}
C程序：
#include <jni.h>
#include <android/log.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <linux/fb.h>
#include <linux/kd.h>
#include <binder/IPCThreadState.h>
#include <binder/ProcessState.h>
#include <binder/IServiceManager.h>
#include <binder/IMemory.h>
#include <surfaceflinger/ISurfaceComposer.h>
#include <SkImageEncoder.h>
#include <SkBitmap.h>
#undef LOG
#define LOG_TAG "logfromc"
#define LOGD(...) __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG, __VA_ARGS__)
#define LOGI(...) __android_log_print(ANDROID_LOG_INFO, LOG_TAG, __VA_ARGS__)
#define LOGE(...) __android_log_print(ANDROID_LOG_ERROR, LOG_TAG, __VA_ARGS__)
namespace android {
static void java_com_android_ScreenCap_ScreenCapNative_nativeCaptureScreen(JNIEnv* env,
jobject obj, jstring file)
{
LOGD("into the native screencap");
const char *file_path = env->GetStringUTFChars(file, NULL);
const String16 name("SurfaceFlinger");
sp<ISurfaceComposer> composer;
getService(name, &composer);
sp<IMemoryHeap> heap;
uint32_t w, h;
PixelFormat f;
status_t err = composer->captureScreen(0, &heap, &w, &h, &f, 0, 0);
if (err != NO_ERROR) {
LOGD("screen capture failed: %s\n", strerror(-err));
exit(0);
}
LOGD("before getbase()");
if(heap==NULL){
LOGD("heap is null!");
}
if(w==0){
LOGD("w is 0!");
}
if(h==0){
LOGD("h is 0!");
}
LOGD("screen capture success: w=%u, h=%u, pixels=%p\n",
w, h, heap->getBase());
LOGD("after getbase()");
LOGD("saving file as jpg in %s ...\n", file_path);
SkBitmap b;
b.setConfig(SkBitmap::kARGB_8888_Config, w, h);
b.setPixels(heap->getBase());
SkImageEncoder::EncodeFile(file_path, b,
SkImageEncoder::kJPEG_Type, SkImageEncoder::kDefaultQuality);
}
static JNINativeMethod gScreenCapNativeMethods[] = {
/* name, signature, funcPtr */
{ "nativeCaptureScreen", "(Ljava/lang/String;)V",
(void*) android_ScreenCap_ScreenCapNative_nativeCaptureScreen },
};
int register_android_ScreenCap_ScreenCapNative(JNIEnv* env) {
int res = jniRegisterNativeMethods(env, "com/android/ScreenCap/ScreenCapNative",
gScreenCapNativeMethods, NELEM(gScreenCapNativeMethods));
LOG_FATAL_IF(res < 0, "Unable to register native methods.");
return 0;
}
extern "C" jint JNI_OnLoad(JavaVM* vm, void* reserved)
{
JNIEnv* env = NULL;
jint result = -1;
if (vm->GetEnv((void**) &env, JNI_VERSION_1_4) != JNI_OK) {
LOGE("GetEnv failed!");
return result;
}
LOG_ASSERT(env, "Could not retrieve the env!");
register_android_ScreenCap_ScreenCapNative(env);
return JNI_VERSION_1_4;
}
} /* namespace android */
Android.mk文件：
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE_TAGS := optional
LOCAL_MODULE := libscreencapjni
LOCAL_SRC_FILES := com_android_screencapture_ScreenCapNative.cpp
LOCAL_SHARED_LIBRARIES := \
libcutils \
libutils \
libbinder \
libskia \
libui \
libsurfaceflinger_client \
libandroid_runtime \
LOCAL_C_INCLUDES += \
$(JNI_H_INCLUDE) \
external/skia/include/core \
external/skia/include/effects \
external/skia/include/images \
external/skia/src/ports \
external/skia/include/utils \
frameworks/base/core/jni/android/graphics \
LOCAL_PRELINK_MODULE := false
LOCAL_PATH:= $(call my-dir)
LOCAL_MODULE_TAGS := optional
LOCAL_SRC_FILES := $(call all-subdir-java-files)
LOCAL_PACKAGE_NAME := ScreenCapture
LOCAL_CERTIFICATE := platform
LOCAL_REQUIRED_MODULES := libscreencapjni
LOCAL_JNI_SHARED_LIBRARIES := libscreencapjni
include $(BUILD_SHARED_LIBRARY)
logcat打印的错误为：
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): FATAL EXCEPTION: main
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): java.lang.UnsatisfiedLinkError: nativeCaptureScreen
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): at com.android.ScreenCap.ScreenCapNative.nativeCaptureScreen(Native Method)
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): at com.android.ScreenCap.ScreenCapNative.startCaptureScreen(ScreenCapNative.java:17)
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): at com.android.ScreenCap.ScreenCapjpgActivity$1.onClick(ScreenCapjpgActivity.java:26)
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): at android.view.View.performClick(View.java:2506)
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): at android.view.View$PerformClick.run(View.java:9112)
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): at android.os.Handler.handleCallback(Handler.java:587)
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): at android.os.Handler.dispatchMessage(Handler.java:92)
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): at android.os.Looper.loop(Looper.java:130)
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): at android.app.ActivityThread.main(ActivityThread.java:3835)
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): at java.lang.reflect.Method.invokeNative(Native Method)
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): at java.lang.reflect.Method.invoke(Method.java:507)
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858)
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
05-24 14:49:06.879: ERROR/AndroidRuntime(8311): at dalvik.system.NativeStart.main(Native Method)
05-24 14:49:06.889: WARN/ActivityManager(294): Force finishing activity com.android.ScreenCap/.ScreenCapjpgActivity
各位大神求助啊！！！！指点下，可以加QQ交流277143127 --------------------编程问答-------------------- 在线等待………… --------------------编程问答-------------------- 若我没有猜错的话，这个好像是要root的权限的吧。 --------------------编程问答-------------------- 你这是C++，不是C
命名空间整个android ，起个跟自己相关的吧，这个太。。。。
java.lang.UnsatisfiedLinkError 这是找不到函数，一般是函数名字弄得不一致了
static void java_com_android_ScreenCap_ScreenCapNative_nativeCaptureScreen
你这个方法是 手动拼的吧？
JAVAH 生成出来是这个格式的 ，你试试
JNIEXPORT void JNICALL java_com_android_ScreenCap_ScreenCapNative_nativeCaptureScreen --------------------编程问答-------------------- 谢谢 我试试 C\C++实在不会 --------------------编程问答-------------------- 函数名字改了也不行 还是那个错 能不能帮忙看下Android.mk配置的对不对 我觉得那里面可能有错 --------------------编程问答-------------------- 工程给我，帮你看看
QQ149603158 --------------------编程问答-------------------- 一般来说可能是JNI库没有打包到APK里，MK文件应该没错，既然你能编译通过。 --------------------编程问答--------------------
有道理，确定打包进去了吗 --------------------编程问答--------------------
格式好乱，能给排版下吗？ --------------------编程问答-------------------- 楼主解决了吗，我也碰到相同的问题了。。。
补充：移动开发 , Android
