android平台led开发之应用层

四,应用层(APP)

 

1,为了方便,使用Eclipse编写一个简单的控制灯的应用,添加四个button,分配控制灯1亮,灯1灭,灯2亮,灯2灭,Activity代码如下

package com.android.swtled;

import android.app.Activity;
import android.os.Bundle;
import android.os.ISwtledService;
import android.os.ServiceManager;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.os.RemoteException;

public class swtled extends Activity {

    private static final String LOG_TAG = "com.android.swtled";
    private ISwtledService swtledService = null;

    private Button setOnLight1Button = null;
    private Button setOffLight1Button = null;
    private Button setOnLight2Button = null;
    private Button setOffLight2Button = null;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        swtledService = ISwtledService.Stub.asInterface(ServiceManager.getService("swtled"));

        setOnLight1Button = (Button)findViewById(R.id.button_seton_light1);
        setOffLight1Button = (Button)findViewById(R.id.button_setoff_light1);
        setOnLight2Button = (Button)findViewById(R.id.button_seton_light2);
        setOffLight2Button = (Button)findViewById(R.id.button_setoff_light2);

        setOnLight1Button.setOnClickListener(new OnClickListener()
        {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub

                try{

                    swtledService.setOn(1);
                }catch(RemoteException e)
                {
                    Log.e(LOG_TAG, "Exception while setOn Light.");

                }
            }

        });

        setOffLight1Button.setOnClickListener(new OnClickListener()
        {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub

                try{

                    swtledService.setOff(1);
                }catch(RemoteException e)
                {
                    Log.e(LOG_TAG, "Exception while setOn Light.");

                }
            }

        });

        setOnLight2Button.setOnClickListener(new OnClickListener()
        {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub

                try{

                    swtledService.setOn(2);
                }catch(RemoteException e)
                {
                    Log.e(LOG_TAG, "Exception while setOn Light.");

                }
            }

        });

        setOffLight2Button.setOnClickListener(new OnClickListener()
        {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub

                try{

                    swtledService.setOff(2);
                }catch(RemoteException e)
                {
                    Log.e(LOG_TAG, "Exception while setOn Light.");

                }
            }
        });
    }
}

2, AndroidManifest.xml脚本

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android=""
      package="com.android.swtled"
      android:versionCode="1"
      android:versionName="1.0">


    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".swtled"
                  android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
</manifest>

3,字符串文件res/values/strings.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="hello">Hello World, swtled!>
    <string name="app_name">swtled</string>
    <string name="seton_light1"></string>
    <string name="setoff_light1"></string>
    <string name="seton_light2"></string>
    <string name="setoff_light2"></string>
</resources>

4,布局文件脚本main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android=""
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
    <TextView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="@string/hello"
    />
    <LinearLayout
          android:layout_width="fill_parent"
          android:layout_height="wrap_content"
          android:orientation="horizontal"
          android:gravity="center">

     <Button
         android:id="@+id/button_seton_light1"
             android:layout_width = "wrap_content"
             android:layout_height = "wrap_content"
             android:text = "@string/seton_light1"
     />

     <Button
     android:id = "@+id/button_setoff_light1"
         android:layout_width = "wrap_content"
         android:layout_height = "wrap_content"
         android:text = "@string/setoff_light1"
     />

     <Button
         android:id="@+id/button_seton_light2"
             android:layout_width = "wrap_content"
             android:layout_height = "wrap_content"
             android:text = "@string/seton_light2"
     />

     <Button
     android:id = "@+id/button_setoff_light2"
         android:layout_width = "wrap_content"
         android:layout_height = "wrap_content"
         android:text = "@string/setoff_light2"
     />
     </LinearLayout>
</LinearLayout>

5,由于是编译器是Eclipse,但实际编译却是要在android源代码环境下编译,于是,将工程目录的三个文件

  src,res以及AndroidManifest.xml复制到gingerbread源码目录的package/experimental/swtled下,其中

  swtled文件是需要自己新建的,复制完成之后,进入编译阶段

 

6,编译app并生成apk文件

  (1) mmm package/experimental/swtled

  编译成功后，便可以在out/target/product/generic/system/app目录下看到swtled.apk文件
  (2) 重新打包系统镜像文件system.img

   make snod

 

7,开机测试

 

 

8,注意事项:

在工程中需要import两个包是
 import android.os.ISwtledService;
 import android.os.ServiceManager;

程序通过ServiceManager.getService("swtled")来获得SwtledService，
接着通过ISwtledService.Stub.asInterface函数转换为ISwtledService接口。
其中，服务名字“swtled”是系统启动时加载SwtledService时指定的，
而ISwtledService接口定义在android.os.ISwtledService中
需要注意的是,虽然用Eclipse编译这个应用,但是无法用Eclipse编译,最后还是需要将工程中res,src以及AndroidManifest.xml三个文件copy到gingerbread/package/experimental/swtled,swtled是自己再新建的文件夹, 然后使用 mmm package/experimental/swtled编译,如果正确,最后会生成.apk文件。

 

9,结束

以上四篇文章记录了在android平台下使用硬件led灯实现从java应用层控制灯的四个实现阶段,这个主要是记录自己的一些心得,在开发阶段也借鉴参考了一些网友的文章,在此表示感谢。