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Thursday, April 26, 2012

how to import android.os.SystemProperties in android app

Please follow the below steps to solve this problem, I solved the same issue

Some properties will not directly accessible to app layer in android, It is need to load the package dynamically, for that need to create a class SystemPropertiesProxy


Copy the below code as it is in SystemPropertiesProxy.java




package com.example.packname;


import java.io.File;

import java.lang.reflect.Method;

import android.content.Context;

import dalvik.system.DexFile;





public class SystemPropertiesProxy

{



/**

 * This class cannot be instantiated

 */

private SystemPropertiesProxy(){



}



    /**

     * Get the value for the given key.

     * @return an empty string if the key isn't found

     * @throws IllegalArgumentException if the key exceeds 32 characters

     */

    public static String get(Context context, String key) throws IllegalArgumentException {



        String ret= "";



        try{



          ClassLoader cl = context.getClassLoader();

          @SuppressWarnings("rawtypes")

          Class SystemProperties = cl.loadClass("android.os.SystemProperties");



          //Parameters Types

          @SuppressWarnings("rawtypes")

              Class[] paramTypes= new Class[1];

          paramTypes[0]= String.class;



          Method get = SystemProperties.getMethod("get", paramTypes);



          //Parameters

          Object[] params= new Object[1];

          params[0]= new String(key);



          ret= (String) get.invoke(SystemProperties, params);



        }catch( IllegalArgumentException iAE ){

            throw iAE;

        }catch( Exception e ){

            ret= "";

            //TODO

        }



        return ret;



    }



    /**

     * Get the value for the given key.

     * @return if the key isn't found, return def if it isn't null, or an empty string otherwise

     * @throws IllegalArgumentException if the key exceeds 32 characters

     */

    public static String get(Context context, String key, String def) throws IllegalArgumentException {



        String ret= def;



        try{



          ClassLoader cl = context.getClassLoader();

          @SuppressWarnings("rawtypes")

          Class SystemProperties = cl.loadClass("android.os.SystemProperties");



          //Parameters Types

          @SuppressWarnings("rawtypes")

              Class[] paramTypes= new Class[2];

          paramTypes[0]= String.class;

          paramTypes[1]= String.class;         



          Method get = SystemProperties.getMethod("get", paramTypes);



          //Parameters

          Object[] params= new Object[2];

          params[0]= new String(key);

          params[1]= new String(def);



          ret= (String) get.invoke(SystemProperties, params);



        }catch( IllegalArgumentException iAE ){

            throw iAE;

        }catch( Exception e ){

            ret= def;

            //TODO

        }



        return ret;



    }



    /**

     * Get the value for the given key, and return as an integer.

     * @param key the key to lookup

     * @param def a default value to return

     * @return the key parsed as an integer, or def if the key isn't found or

     *         cannot be parsed

     * @throws IllegalArgumentException if the key exceeds 32 characters

     */

    public static Integer getInt(Context context, String key, int def) throws IllegalArgumentException {



        Integer ret= def;



        try{



          ClassLoader cl = context.getClassLoader();

          @SuppressWarnings("rawtypes")

          Class SystemProperties = cl.loadClass("android.os.SystemProperties");



          //Parameters Types

          @SuppressWarnings("rawtypes")

              Class[] paramTypes= new Class[2];

          paramTypes[0]= String.class;

          paramTypes[1]= int.class; 



          Method getInt = SystemProperties.getMethod("getInt", paramTypes);



          //Parameters

          Object[] params= new Object[2];

          params[0]= new String(key);

          params[1]= new Integer(def);



          ret= (Integer) getInt.invoke(SystemProperties, params);



        }catch( IllegalArgumentException iAE ){

            throw iAE;

        }catch( Exception e ){

            ret= def;

            //TODO

        }



        return ret;



    }



    /**

     * Get the value for the given key, and return as a long.

     * @param key the key to lookup

     * @param def a default value to return

     * @return the key parsed as a long, or def if the key isn't found or

     *         cannot be parsed

     * @throws IllegalArgumentException if the key exceeds 32 characters

     */

    public static Long getLong(Context context, String key, long def) throws IllegalArgumentException {



        Long ret= def;



        try{



          ClassLoader cl = context.getClassLoader();

          @SuppressWarnings("rawtypes")

              Class SystemProperties= cl.loadClass("android.os.SystemProperties");



          //Parameters Types

          @SuppressWarnings("rawtypes")

              Class[] paramTypes= new Class[2];

          paramTypes[0]= String.class;

          paramTypes[1]= long.class; 



          Method getLong = SystemProperties.getMethod("getLong", paramTypes);



          //Parameters

          Object[] params= new Object[2];

          params[0]= new String(key);

          params[1]= new Long(def);



          ret= (Long) getLong.invoke(SystemProperties, params);



        }catch( IllegalArgumentException iAE ){

            throw iAE;

        }catch( Exception e ){

            ret= def;

            //TODO

        }



        return ret;



    }



    /**

     * Get the value for the given key, returned as a boolean.

     * Values 'n', 'no', '0', 'false' or 'off' are considered false.

     * Values 'y', 'yes', '1', 'true' or 'on' are considered true.

     * (case insensitive).

     * If the key does not exist, or has any other value, then the default

     * result is returned.

     * @param key the key to lookup

     * @param def a default value to return

     * @return the key parsed as a boolean, or def if the key isn't found or is

     *         not able to be parsed as a boolean.

     * @throws IllegalArgumentException if the key exceeds 32 characters

     */

    public static Boolean getBoolean(Context context, String key, boolean def) throws IllegalArgumentException {



        Boolean ret= def;



        try{



          ClassLoader cl = context.getClassLoader();

          @SuppressWarnings("rawtypes")

          Class SystemProperties = cl.loadClass("android.os.SystemProperties");



          //Parameters Types

          @SuppressWarnings("rawtypes")

              Class[] paramTypes= new Class[2];

          paramTypes[0]= String.class;

          paramTypes[1]= boolean.class; 



          Method getBoolean = SystemProperties.getMethod("getBoolean", paramTypes);



          //Parameters       

          Object[] params= new Object[2];

          params[0]= new String(key);

          params[1]= new Boolean(def);



          ret= (Boolean) getBoolean.invoke(SystemProperties, params);



        }catch( IllegalArgumentException iAE ){

            throw iAE;

        }catch( Exception e ){

            ret= def;

            //TODO

        }



        return ret;



    }



    /**

     * Set the value for the given key.

     * @throws IllegalArgumentException if the key exceeds 32 characters

     * @throws IllegalArgumentException if the value exceeds 92 characters

     */

    public static void set(Context context, String key, String val) throws IllegalArgumentException {



        try{



          @SuppressWarnings("unused")

          DexFile df = new DexFile(new File("/system/app/Settings.apk"));

          @SuppressWarnings("unused")

          ClassLoader cl = context.getClassLoader();

          @SuppressWarnings("rawtypes")

          Class SystemProperties = Class.forName("android.os.SystemProperties");



          //Parameters Types

          @SuppressWarnings("rawtypes")

              Class[] paramTypes= new Class[2];

          paramTypes[0]= String.class;

          paramTypes[1]= String.class; 



          Method set = SystemProperties.getMethod("set", paramTypes);



          //Parameters       

          Object[] params= new Object[2];

          params[0]= new String(key);

          params[1]= new String(val);



          set.invoke(SystemProperties, params);



        }catch( IllegalArgumentException iAE ){

            throw iAE;

        }catch( Exception e ){

            //TODO

        }



    }

}
----------------------------------------------------------------------------------------------------------------------

Calling in your code

import com.example.packname.*;

String property = SystemPropertiesProxy.get(this, "sys.boot_completed");


Thus your problem gets solved.



1 comment:

  1. cannot help please give solution step by step....

    ReplyDelete