我正在按照本教程中的指南编写一个非常简单的应用程序。
我尝试运行我的应用程序,但在打开时失败。编写的 C 代码已使用ndk-build
.
这是Java代码:
package com.example.ndktest;
import android.os.Bundle;
import android.app.Activity;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.support.v4.app.NavUtils;
public class MainActivity extends Activity {
private Button button;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.i( "MainActivity", "beginning of onCreate()" );
setContentView(R.layout.activity_main);
button = (Button) findViewById( R.id.button1 );
button.setOnClickListener( new OnClickListener( ) {
public void onClick(View arg0) {
// TODO Auto-generated method stub
helloLog( "This will log to LogCat" );
}
});
}
private native void helloLog( String logThis );
static {
System.loadLibrary( "ndk1" );
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
}
这是C代码:
#include <jni.h>
#include <string.h>
#include <android/log.h>
#define DEBUG_TAG "NDK_AndroidNDK1SampleActivity"
void Java_com_example_ndktest_MainActivity_helloLog( JNIEnv * env, jobject this, jstring logThis )
{
jboolean isCopy;
const char * szLogThis = (*env)->GetStringUTFChars( env, logThis, &isCopy );
__android_log_print( ANDROID_LOG_DEBUG, DEBUG_TAG, "NDK:LC: [%s]", szLogThis );
(*env)->ReleaseStringUTFChars( env, logThis, szLogThis );
}
这是MakeFile:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_LDLIBS := -llog
LOCAL_MODULE := ndk1
LOCAL_SRC_FILES := native.c
include $(BUILD_SHARED_LIBRARY)
这是 XML 文件:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:padding="@dimen/padding_medium"
android:text="@string/hello_world"
tools:context=".MainActivity" />
<Button
android:id="@+id/button1"
android:layout_width="fill_parent"
android:text="Click Here to Log" />
</RelativeLayout>
这是 AndroidManifest :
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.ndktest"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="15" />
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="@string/title_activity_main" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
这是我在 Eclipse 中的环境图片:
编辑 :
发现 LogCat 确实显示了一些东西,但它们被过滤器隐藏了......仍然无法找出问题所在。这是 LogCat:
07-30 15:22:31.718: E/AndroidRuntime(2589): FATAL EXCEPTION: main
07-30 15:22:31.718: E/AndroidRuntime(2589): java.lang.ExceptionInInitializerError
07-30 15:22:31.718: E/AndroidRuntime(2589): at java.lang.Class.newInstanceImpl(Native Method)
07-30 15:22:31.718: E/AndroidRuntime(2589): at java.lang.Class.newInstance(Class.java:1409)
07-30 15:22:31.718: E/AndroidRuntime(2589): at android.app.Instrumentation.newActivity(Instrumentation.java:1021)
07-30 15:22:31.718: E/AndroidRuntime(2589): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1561)
07-30 15:22:31.718: E/AndroidRuntime(2589): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
07-30 15:22:31.718: E/AndroidRuntime(2589): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
07-30 15:22:31.718: E/AndroidRuntime(2589): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
07-30 15:22:31.718: E/AndroidRuntime(2589): at android.os.Handler.dispatchMessage(Handler.java:99)
07-30 15:22:31.718: E/AndroidRuntime(2589): at android.os.Looper.loop(Looper.java:130)
07-30 15:22:31.718: E/AndroidRuntime(2589): at android.app.ActivityThread.main(ActivityThread.java:3683)
07-30 15:22:31.718: E/AndroidRuntime(2589): at java.lang.reflect.Method.invokeNative(Native Method)
07-30 15:22:31.718: E/AndroidRuntime(2589): at java.lang.reflect.Method.invoke(Method.java:507)
07-30 15:22:31.718: E/AndroidRuntime(2589): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
07-30 15:22:31.718: E/AndroidRuntime(2589): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
07-30 15:22:31.718: E/AndroidRuntime(2589): at dalvik.system.NativeStart.main(Native Method)
07-30 15:22:31.718: E/AndroidRuntime(2589): Caused by: java.lang.UnsatisfiedLinkError: Couldn't load ndk1: findLibrary returned null
07-30 15:22:31.718: E/AndroidRuntime(2589): at java.lang.Runtime.loadLibrary(Runtime.java:429)
07-30 15:22:31.718: E/AndroidRuntime(2589): at java.lang.System.loadLibrary(System.java:554)
07-30 15:22:31.718: E/AndroidRuntime(2589): at com.example.ndktest.MainActivity.<clinit>(MainActivity.java:38)
07-30 15:22:31.718: E/AndroidRuntime(2589): ... 15 more
07-30 15:22:31.718: W/ActivityManager(1136): Force finishing activity com.example.ndktest/.MainActivity
编辑 2:
这是我调用 ndk-build 后我的 cygwin 终端的图片: