Developing Android apps to use hardware access services

1. Develop Android app to use hardware Access Service

~/android-2.3_r1/packages/experimental/freg

----Androidmanifest.java

----ANDROID.MK

----SRC

----Shy/luo/freg

----Freg.java

----Res

----layout

----Main.xml

----values

----String.xml

----drawable

----Icon.png

Freg.java

Package Shy.luo.freg;import Android.app.activity;import Android.os.servicemanager;import android.os.Bundle;import Android.os.ifregservice;import Android.os.remoteexception;import Android.util.log;import Android.view.View;import Android.view.view.onclicklistener;import Android.widget.button;import Android.widget.edittext;public class Freg Extends Activity implements Onclicklistener {private final static String Log_tag = "shy.luo.freg.FregActivity";p rivate IF Regservice fregservice = null;private EditText valueText = null;private button Readbutton = null;private button Writebutto    n = null;private Button Clearbutton = null; /** called when the activity is first created.        */@Override public void OnCreate (Bundle savedinstancestate) {super.oncreate (savedinstancestate);                Setcontentview (r.layout.main); fregservice = IFregService.Stub.asInterface (Servicemanager.getservice ("Freg"));        ValueText = (EditText) Findviewbyid (R.id.edit_value); Readbutton = (ButtoN) Findviewbyid (r.id.button_read);        Writebutton = (Button) Findviewbyid (r.id.button_write); Clearbutton = (Button) Findviewbyid (r.id.button_clear); Readbutton.setonclicklistener (this);                Writebutton.setonclicklistener (This), Clearbutton.setonclicklistener (this);    LOG.I (Log_tag, "Freg Activity Created");    } @Override public void OnClick (View v) {if (V.equals (Readbutton)) {try {int val = fregservice.getval ();    String Text = string.valueof (val); Valuetext.settext (text);}    catch (RemoteException e) {log.e (Log_tag, "Remote Exception while reading value from Freg service.");    } else if (V.equals (Writebutton)) {try {String text = Valuetext.gettext (). toString (); int val = integer.parseint (text); Fregservice.setval (val);}    catch (RemoteException e) {log.e (Log_tag, "Remote Exception while writing value to Freg service.");    } else if (V.equals (Clearbutton)) {String text = "";    Valuetext.settext (text); }    }}

Main.xml

<?xml version= "1.0" encoding= "Utf-8"? ><linearlayout xmlns:android= "http://schemas.android.com/apk/res/    Android "android:orientation=" vertical "android:layout_width=" fill_parent "android:layout_height=" Fill_parent " > <linearlayout android:layout_width= "fill_parent" android:layout_height= "Wrap_content" Android:orienta tion= "vertical" android:gravity= "center" > <textview android:layout_width= "wrap_content" Android:layout_ height= "Wrap_content" android:text= "@string/value" > </TextView> <edittext android:layout_wi Dth= "Fill_parent" android:layout_height= "wrap_content" android:id= "@+id/edit_value" android:hint= "@s    Tring/hint "> </EditText> </LinearLayout> <linearlayout android:layout_width=" Fill_parent "     android:layout_height= "wrap_content" android:orientation= "horizontal" android:gravity= "center" > <Button  Android:id= "@+id/button_read"  Android:layout_width= "Wrap_content" android:layout_height= "wrap_content" android:text= "@string/read" > </B utton> <button android:id= "@+id/button_write" android:layout_width= "Wrap_content" android:layout_height    = "Wrap_content" android:text= "@string/write" > </Button> <button android:id= "@+id/button_clear" Android:layout_width= "Wrap_content" android:layout_height= "wrap_content" android:text= "@string/clear" > </B Utton> </LinearLayout></LinearLayout>

Strings.xml

<?xml version= "1.0" encoding= "Utf-8"?><resources>    <string name= "App_name" >freg</string >    <string name= "value" >Value</string>    <string name= "hint" >please input a value...</ string>    <string name= "read" >Read</string>    <string name= "Write" >Write</string>    <string name= "Clear" >Clear</string></resources>

Androidmanifest.xml

<?xml version= "1.0" encoding= "Utf-8"? ><manifest xmlns:android= "http://schemas.android.com/apk/res/ Android "      package=" Shy.luo.freg "      android:versioncode=" 1 "      android:versionname=" 1.0 ">    < Application android:icon= "@drawable/icon" android:label= "@string/app_name" >        <activity android:name= ". Freg "                  android:label=" @string/app_name ">            <intent-filter>                <action android:name=" Android.intent.action.MAIN "/>                <category android:name=" Android.intent.category.LAUNCHER "/>            < /intent-filter>        </activity>    

Android.mk

Local_path:= $ (call My-dir) include $ (clear_vars) Local_module_tags: = Optionallocal_src_files: = $ (call All-subdir-java-files) Local_package_name: = Freginclude $ (build_package)

2. Compiling

Compile into apk:

The generated freg.apk is located in Out/target/product/generic/system/app.

Packaged:

Finally, the freg.apk is repackaged into the system.img, located in Out/target/product/gerneric.

Run:

The results are as follows: