android之应用程序LED(1)

参考友善的LED程序，自己也写了个，不是用友善的libfriendlyarm-hardware.so，自己用NDK中的例子hello-jni写了个程序，已经编译成libhello-jni.so，可惜上不了图。

自己摸索了好久总算有点收获，感谢各位网友的帮忙。部门源码贴出来给大家参考！ 刚搞完就拿出来分享了，欢迎大家指正。有谁想看libfriendlyarm-hardware.so的源码的可以参考这

个。

JNI部分 用C语言实现

 

复制代码

1. /*
2. * Copyright (C) 2009 The Android Open Source Project
3. *
4. * Licensed under the Apache License, Version 2.0 (the "License");
5. * you may not use this file except in compliance with the License.
6. * You may obtain a copy of the License at
7. *
8. * http://www.apache.org/licenses/LICENSE-2.0
9. *
10. * Unless required by applicable law or agreed to in writing, software
11. * distributed under the License is distributed on an "AS IS" BASIS,
12. * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13. * See the License for the specific language governing permissions and
14. * limitations under the License.
15. *
16. */
17. #include <string.h>
18. #include <jni.h>
19. #include <fcntl.h> /*包括文件操作，如open() read() close()write()等*/
20. int fd;
21. /* This is a trivial JNI example where we use a native method
22. * to return a new VM String. See the corresponding Java source
23. * file located at:
24. *
25. * apps/samples/hello-jni/project/src/com/example/HelloJni/HelloJni.java
26. */
27. jstring
28. Java_com_helloworld_helloworld_stringFromJNI( JNIEnv* env,
29. jobject thiz )
30. {
31. return (*env)->NewStringUTF(env, "Hello from JNI create by carlin !");
32. }
33. jint Java_com_helloworld_helloworld_openled( JNIEnv* env,
34. jobject thiz )
35. {
36. fd = open("/dev/leds0", O_RDONLY);
37. if (fd < 0)
38. {
39. fd = open("/dev/leds", O_RDONLY);
40. return 1;
41. }
42. return 0;
43. }
44. jint Java_com_helloworld_helloworld_setLedState( JNIEnv* env,
45. jobject thiz ,jint ledID,jint ledState)
46. {
47. ioctl(fd,ledState, ledID);
48. return 1;
49. }
50. jint Java_com_helloworld_helloworld_closeled( JNIEnv* env,
51. jobject thiz )
52. {
53. close(fd);
54. return 1;
55. }

APP部分即JAVA

 

复制代码

1. package com.helloworld;
2. import android.app.Activity;
3. import android.widget.TextView;
4. import android.os.Bundle;
5. import android.view.View;
6. import android.widget.Button;
7. import android.view.View.OnClickListener;
8. public class helloworld extends Activity {
9.  
10.  private Button btnLED1On;
11.  private Button btnLED1Off;
12.     /** Called when the activity is first created. */
13.     @Override
14.     public void onCreate(Bundle savedInstanceState)
15.     {
16.         super.onCreate(savedInstanceState);
17.         setContentView(R.layout.main);
18.        
19.         openled();
20.        
21.      btnLED1On = (Button)findViewById(R.id.btnLED1On);
22.      btnLED1Off = (Button)findViewById(R.id.btnLED1Off);
23.      
24.      btnLED1On.setOnClickListener(new View.OnClickListener()
25.      {
26.       public void onClick(View v) /**当按钮按下*/
27.       {
28.        setLedState(0,1);
29.       }
30.      }
31.      );
32.      
33.      btnLED1Off.setOnClickListener(new View.OnClickListener()
34.      {
35.       public void onClick(View v) /**当按钮按下*/
36.       {
37.        setLedState(0,0);
38.       }
39.      }
40.      );
41.     }
42.     /* A native method that is implemented by the
43.      * 'hello-jni' native library, which is packaged
44.      * with this application.
45.      */
46.     public native String  stringFromJNI();
47.     public native int openled();
48.     public native int setLedState(int ledID,int ledState);
49.     public native int closeled();
50.     /* This is another native method declaration that is *not*
51.      * implemented by 'hello-jni'. This is simply to show that
52.      * you can declare as many native methods in your Java code
53.      * as you want, their implementation is searched in the
54.      * currently loaded native libraries only the first time
55.      * you call them.
56.      *
57.      * Trying to call this function will result in a
58.      * java.lang.UnsatisfiedLinkError exception !
59.      */
60.     public native String  unimplementedStringFromJNI();
61.     /* this is used to load the 'hello-jni' library on application
62.      * startup. The library has already been unpacked into
63.      * /data/data/com.example.HelloJni/lib/libhello-jni.so at
64.      * installation time by the package manager.
65.      */
66.     static {
67.         System.loadLibrary("hello-jni");
68.     }
69. }

[ 此帖被carlin在2011-08-04 22:47重新编辑 ]