android开发工具类，不怕用不到，就怕用时找不到
前几天项目刚上线不久，现在有点闲时间，把开发中用到的常用工具整理下，当作笔记。同大家分享，如果能帮到大家，深感荣幸。
public final class SystemTool {
/**
* 指定格式返回当前系统时间
*/
public static String getDataTime(String format) {
SimpleDateFormat df = new SimpleDateFormat(format);
return df.format(new Date());
}
/**
* 返回当前系统时间(格式以HH:mm形式)
*/
public static String getDataTime() {
return getDataTime("HH:mm");
}
/**
* 获取手机IMEI码
*/
public static String getPhoneIMEI(Context cxt) {
TelephonyManager tm = (TelephonyManager) cxt.getSystemService(Context.TELEPHONY_SERVICE);
return tm.getDeviceId();
}
/**
* 获取手机系统SDK版本
*
* @return 如API 17 则返回 17
*/
public static int getSDKVersion() {
return android.os.Build.VERSION.SDK_INT;
}
/**
* 获取系统版本
*
* @return 形如2.3.3
*/
public static String getSystemVersion() {
return android.os.Build.VERSION.RELEASE;
}
/**
* 调用系统发送短信
*/
public static void sendSMS(Context cxt, String smsBody) {
Uri smsToUri = Uri.parse("smsto:");
Intent intent = new Intent(Intent.ACTION_SENDTO, smsToUri);
intent.putExtra("sms_body", smsBody);
cxt.startActivity(intent);
}
/**
* 判断网络是否连接
*/
public static boolean checkNet(Context context) {
ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo info = cm.getActiveNetworkInfo();
return info != null;// 网络是否连接
}
/**
* 判断是否为wifi联网
*/
public static boolean isWiFi(Context cxt) {
ConnectivityManager cm = (ConnectivityManager) cxt.getSystemService(Context.CONNECTIVITY_SERVICE);
// wifi的状态：ConnectivityManager.TYPE_WIFI
// 3G的状态：ConnectivityManager.TYPE_MOBILE
State state = cm.getNetworkInfo(ConnectivityManager.TYPE_WIFI).getState();
return State.CONNECTED == state;
}
/**
* 隐藏系统键盘
* 警告 必须是确定键盘显示时才能调用
*/
public static void hideKeyBoard(Activity aty) {
((InputMethodManager) aty.getSystemService(Context.INPUT_METHOD_SERVICE)).hideSoftInputFromWindow(aty.getCurrentFocus().getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);
}
/**
* 判断当前应用程序是否后台运行
*/
public static boolean isBackground(Context context) {
ActivityManager activityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
List
for (ActivityManager.RunningAppProcessInfo appProcess : appProcesses) {
if (appProcess.processName.equals(context.getPackageName())) {
if (appProcess.importance == ActivityManager.RunningAppProcessInfo.IMPORTANCE_BACKGROUND) {
// 后台运行
return true;
} else {
// 前台运行
return false;
}
}
}
return false;
}
/**
* 判断手机是否处理睡眠
*/
public static boolean isSleeping(Context context) {
KeyguardManager kgMgr = (KeyguardManager) context.getSystemService(Context.KEYGUARD_SERVICE);
boolean isSleeping = kgMgr.inKeyguardRestrictedInputMode();
return isSleeping;
}
/**
* 安装apk
*
* @param context
* @param file
*/
public static void installApk(Context context, File file) {
Intent intent = new Intent();
intent.setAction("android.intent.action.VIEW");
intent.addCategory("android.intent.category.DEFAULT");
intent.setType("application/vnd.android.package-archive");
intent.setData(Uri.fromFile(file));
intent.setDataAndType(Uri.fromFile(file), "application/vnd.android.package-archive");
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(intent);
}
/**
* 获取当前应用程序的版本号
*/
public static String getAppVersion(Context context) {
String version = "0";
try {
version = context.getPackageManager().getPackageInfo(context.getPackageName(), 0).versionName;
} catch (PackageManager.NameNotFoundException e) {
throw new KJException(SystemTool.class.getName() + "the application not found");
}
return version;
}
/**
* 回到home，后台运行
*/
public static void goHome(Context context) {
Intent mHomeIntent = new Intent(Intent.ACTION_MAIN);
mHomeIntent.addCategory(Intent.CATEGORY_HOME);
mHomeIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED);
context.startActivity(mHomeIntent);
}
/**
* 获取应用签名
*
* @param context
* @param pkgName
*/
public static String getSign(Context context, String pkgName) {
try {
PackageInfo pis = context.getPackageManager().getPackageInfo(pkgName, PackageManager.GET_SIGNATURES);
return hexdigest(pis.signatures[0].toByteArray());
} catch (NameNotFoundException e) {
throw new KJException(SystemTool.class.getName() + "the " + pkgName + "'s application not found");
}
}
/**
* 将签名字符串转换成需要的32位签名
*/
private static String hexdigest(byte[] paramArrayOfByte) {
final char[] hexDigits = { 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 97, 98, 99, 100, 101, 102 };
try {
MessageDigest localMessageDigest = MessageDigest.getInstance("MD5");
localMessageDigest.update(paramArrayOfByte);
byte[] arrayOfByte = localMessageDigest.digest();
char[] arrayOfChar = new char[32];
for (int i = 0, j = 0;; i++, j++) {
if (i >= 16) { return new String(arrayOfChar); }
int k = arrayOfByte[i];
arrayOfChar[j] = hexDigits[(0xF & k >>> 4)];
arrayOfChar[++j] = hexDigits[(k & 0xF)];
}
} catch (Exception e) {}
return "";
}
/**
* 获取设备的可用内存大小
*
* @param cxt
* 应用上下文对象context
* @return 当前内存大小
*/
public static int getDeviceUsableMemory(Context cxt) {
ActivityManager am = (ActivityManager) cxt.getSystemService(Context.ACTIVITY_SERVICE);
MemoryInfo mi = new MemoryInfo();
am.getMemoryInfo(mi);
// 返回当前系统的可用内存
return (int) (mi.availMem / (1024 * 1024));
}
/**
* 清理后台进程与服务
*
* @param cxt
* 应用上下文对象context
* @return 被清理的数量
*/
public static int gc(Context cxt) {
long i = getDeviceUsableMemory(cxt);
int count = 0; // 清理掉的进程数
ActivityManager am = (ActivityManager) cxt.getSystemService(Context.ACTIVITY_SERVICE);
// 获取正在运行的service列表
List
if (serviceList != null) for (RunningServiceInfo service : serviceList) {
if (service.pid == android.os.Process.myPid()) continue;
try {
android.os.Process.killProcess(service.pid);
count++;
} catch (Exception e) {
e.getStackTrace();
continue;
}
}
// 获取正在运行的进程列表
List
if (processList != null) for (RunningAppProcessInfo process : processList) {
// 一般数值大于RunningAppProcessInfo.IMPORTANCE_SERVICE的进程都长时间没用或者空进程了
// 一般数值大于RunningAppProcessInfo.IMPORTANCE_VISIBLE的进程都是非可见进程，也就是在后台运行着
if (process.importance > RunningAppProcessInfo.IMPORTANCE_VISIBLE) {
// pkgList 得到该进程下运行的包名
String[] pkgList = process.pkgList;
for (String pkgName : pkgList) {
try {
am.killBackgroundProcesses(pkgName);
count++;
} catch (Exception e) { // 防止意外发生
e.getStackTrace();
continue;
}
}
}
}
//"清理了" + (getDeviceUsableMemory(cxt) - i) + "M内存";
return count;
}
}