android实用功能介绍,Android几个实用的小功能实现

//获取当前活动的activity所在的包名

public String getAppPackageName(Context context){

ActivityManager activityManager &＃61; (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);

List taskInfo &＃61; activityManager.getRunningTasks(1);

ComponentName componentInfo &＃61; taskInfo.get(0).topActivity;

Log.d(TAG, "package:" &＃43; componentInfo.getPackageName());

return componentInfo.getPackageName();

}

//获取当前活动activity名称

public String getRunningActivityName(Context context) {

ActivityManager activityManager&＃61;(ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);

//

String runningActivity&＃61;activityManager.getRunningTasks(1).get(0).topActivity.getClassName();

String contextActivity &＃61; runningActivity.substring(runningActivity.lastIndexOf(".")&＃43;1);

Log.d(TAG, "contextActivity:" &＃43; contextActivity);

return contextActivity;

}

//SharedPreferences存取简单数据的例子

public void setStartBTprtValue(String bStart) {

SharedPreferences mySharedPreferences&＃61; getSharedPreferences("StartBTprt",

Activity.MODE_PRIVATE);

SharedPreferences.Editor editor &＃61; mySharedPreferences.edit();

editor.putString("bStart", bStart);

editor.commit();

}

public String getStartBTprtValue() {

SharedPreferences sharedPreferences&＃61; getSharedPreferences("StartBTprt",

Activity.MODE_PRIVATE);

String bStart &＃61;sharedPreferences.getString("bStart", "");

return bStart;

}

//数据转换

public int byte2unsignedint(byte a)

{

int b &＃61; a & 0xff;

return b;

}

public String bytetoString(byte[] bytearray) {

String result &＃61; "";

char temp;

int length &＃61; bytearray.length;

for (int i &＃61; 0; i

temp &＃61; (char) bytearray[i];

result &＃43;&＃61; temp;

}

return result;

}

//java 合并两个byte数组

public byte[] byteMerger(byte[] byte_1, byte[] byte_2){

byte[] byte_3 &＃61; new byte[byte_1.length&＃43;byte_2.length];

System.arraycopy(byte_1, 0, byte_3, 0, byte_1.length);

System.arraycopy(byte_2, 0, byte_3, byte_1.length, byte_2.length);

return byte_3;

}

//删除文件

public void DeleteFile(File file) {

if (file.exists() &＃61;&＃61; false) {

Log.e("www","DeleteFile not exists!!!");

return;

} else {

if (file.isFile()) {

file.delete();

Log.e("www","DeleteFile 1 ok!!!");

return;

}

if (file.isDirectory()) {

File[] childFile &＃61; file.listFiles();

if (childFile &＃61;&＃61; null || childFile.length &＃61;&＃61; 0) {

file.delete();

return;

}

for (File f : childFile) {

DeleteFile(f);

}

file.delete();

Log.e("www","DeleteFile ok!!!");

}

}

}

/**

* 复制单个文件

* &＃64;param oldPath String 原文件路径 如&＃xff1a;c:/fqf.txt

* &＃64;param newPath String 复制后路径 如&＃xff1a;f:/fqf.txt

* &＃64;return

*/

public void copyFile(String oldPath, String newPath) {

try {

int bytesum &＃61; 0;

int byteread &＃61; 0;

File oldfile &＃61; new File(oldPath);

if (oldfile.exists()) { //文件不存在时

InputStream inStream &＃61; new FileInputStream(oldPath);

FileOutputStream fs &＃61; new FileOutputStream(newPath);

byte[] buffer &＃61; new byte[1444];

while ( (byteread &＃61; inStream.read(buffer)) !&＃61; -1) {

bytesum &＃43;&＃61; byteread; //字节数 文件大小

System.out.println(bytesum);

fs.write(buffer, 0, byteread);

}

inStream.close();

fs.close();

}

}

catch (Exception e) {

System.out.println("复制单个文件操作出错");

e.printStackTrace();

}

}

//write data to file in SD

public void writeFileSdcardFile(String fileName,String write_str) throws IOException{

try{

FileOutputStream fout &＃61; new FileOutputStream(fileName);

byte [] bytes &＃61; write_str.getBytes();

fout.write(bytes);

fout.close();

}

catch(Exception e){

e.printStackTrace();

}

}

//read data from SD

public String readFileSdcardFile(String fileName) throws IOException{

String res&＃61;"";

try{

FileInputStream fin &＃61; new FileInputStream(fileName);

int length &＃61; fin.available();

byte [] buffer &＃61; new byte[length];

fin.read(buffer);

res &＃61; EncodingUtils.getString(buffer, "UTF-8");

fin.close();

}

catch(Exception e){

e.printStackTrace();

}

return res;

}

//2 read data from SD//161020

public byte [] readByteSdcardFile(String fileName) throws IOException{

//String res&＃61;"";

try{

FileInputStream fin &＃61; new FileInputStream(fileName);

int length &＃61; fin.available();

byte [] buffer &＃61; new byte[length];

fin.read(buffer);

//res &＃61; EncodingUtils.getString(buffer, "UTF-8");

fin.close();

return buffer;

}

catch(Exception e){

e.printStackTrace();

}

return null;

}

//run linux cmd

String do_exec(String cmd) {

String s &＃61; "/n";

try {

Process p &＃61; Runtime.getRuntime().exec(cmd);

BufferedReader in &＃61; new BufferedReader(

new InputStreamReader(p.getInputStream()));

String line &＃61; null;

while ((line &＃61; in.readLine()) !&＃61; null) {

s &＃43;&＃61; line &＃43; "/n";

}

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

//text.setText(s);

return cmd;

}

public static String str2HexStr(String str) {

char[] chars &＃61; "0123456789ABCDEF".toCharArray();

StringBuilder sb &＃61; new StringBuilder("");

byte[] bs &＃61; str.getBytes();

int bit;

for (int i &＃61; 0; i

bit &＃61; (bs[i] & 0x0f0) >> 4;

sb.append(chars[bit]);

bit &＃61; bs[i] & 0x0f;

sb.append(chars[bit]);

}

return sb.toString();

}

//byteTo16HexStr//161020

public static String bytesToHexString(byte[] bArray) {

StringBuffer sb &＃61; new StringBuffer(bArray.length);

String sTemp;

for (int i &＃61; 0; i

sTemp &＃61; Integer.toHexString(0xFF & bArray[i]);

if (sTemp.length() <2)

sb.append(0);

sb.append(sTemp.toUpperCase());

}

return sb.toString();

}

//读取系统属性

String getproduct &＃61; getSystemProperty("ro.epay.serial","1");

/**

* 读取属性

* */

public String getSystemProperty(String key, String def) {

String result &＃61; null;

try {

Class spCls &＃61; Class.forName("android.os.SystemProperties");

Class[] typeArgs &＃61; new Class[2];

typeArgs[0] &＃61; String.class;

typeArgs[1] &＃61; String.class;

Constructor spcs &＃61; spCls.getConstructor(null);

Object[] valueArgs &＃61; new Object[2];

valueArgs[0] &＃61; key;

valueArgs[1] &＃61; def;

Object sp &＃61; spcs.newInstance(null);

Method method &＃61; spCls.getMethod("get", typeArgs);

result &＃61; (String) method.invoke(sp, valueArgs);

} catch (ClassNotFoundException e) {

e.printStackTrace();

} catch (NoSuchMethodException e) {

e.printStackTrace();

} catch (IllegalAccessException e) {

e.printStackTrace();

} catch (InvocationTargetException e) {

e.printStackTrace();

} catch (InstantiationException e) {

e.printStackTrace();

}

return result;

}