實例詳解Android快速開發工具類總結

一、日志工具類 Log.java

public class L 
{ 
private L() 
{ 
/* 不可被實例化 */ 
throw new UnsupportedOperationException("Cannot be instantiated!"); 
} 
// 是否需要打印bug，可以在application的onCreate函數裡面初始化 
public static boolean isDebug = true; 
private static final String TAG = "DefaultTag"; 
// 下面四個是默認tag的函數 
public static void i(String msg) 
{ 
if (isDebug) 
Log.i(TAG, msg); 
} 
public static void d(String msg) 
{ 
if (isDebug) 
Log.d(TAG, msg); 
} 
public static void e(String msg) 
{ 
if (isDebug) 
Log.e(TAG, msg); 
} 
public static void v(String msg) 
{ 
if (isDebug) 
Log.v(TAG, msg); 
} 
// 下面是傳入自定義tag的函數 
public static void i(String tag, String msg) 
{ 
if (isDebug) 
Log.i(tag, msg); 
} 
public static void d(String tag, String msg) 
{ 
if (isDebug) 
Log.i(tag, msg); 
} 
public static void e(String tag, String msg) 
{ 
if (isDebug) 
Log.i(tag, msg); 
} 
public static void v(String tag, String msg) 
{ 
if (isDebug) 
Log.i(tag, msg); 
} 
}

二、Toast統一管理類 Tost.java

public class T 
{ 
private T() 
{ 
/* cannot be instantiated */ 
throw new UnsupportedOperationException("cannot be instantiated"); 
} 
public static boolean isShow = true; 
/** 
* 短時間顯示Toast 
*/ 
public static void showShort(Context context, CharSequence message) 
{ 
if (isShow) 
Toast.makeText(context, message, Toast.LENGTH_SHORT).show(); 
} 
/** 
* 短時間顯示Toast 
* @param message 要顯示的字符串資源的id
*/ 
public static void showShort(Context context, int message) 
{ 
if (isShow) 
Toast.makeText(context, message, Toast.LENGTH_SHORT).show(); 
} 
/** 
* 長時間顯示Toast 
*/ 
public static void showLong(Context context, CharSequence message) 
{ 
if (isShow) 
Toast.makeText(context, message, Toast.LENGTH_LONG).show(); 
} 
/** 
* 長時間顯示Toast 
*/ 
public static void showLong(Context context, int message) 
{ 
if (isShow) 
Toast.makeText(context, message, Toast.LENGTH_LONG).show(); 
} 
/** 
* 自定義顯示Toast時間 
*/ 
public static void show(Context context, CharSequence message, int duration) 
{ 
if (isShow) 
Toast.makeText(context, message, duration).show(); 
} 
/** 
* 自定義顯示Toast時間 
*/ 
public static void show(Context context, int message, int duration) 
{ 
if (isShow) 
Toast.makeText(context, message, duration).show(); 
} 
}

三、SharedPreferences封裝類 SPUtils.java 和 PreferencesUtils.java

1. SPUtils.java

public class SPUtils 
{ 
/** 
* 保存在手機裡面的文件名 
*/ 
public static final String FILE_NAME = "share_data"; 
/** 
* 保存數據的方法，我們需要拿到保存數據的具體類型，然後根據類型調用不同的保存方法 
* 
* @param context 
* @param key 
* @param object 
*/ 
public static void put(Context context, String key, Object object) 
{ 
SharedPreferences sp = context.getSharedPreferences(FILE_NAME, 
Context.MODE_PRIVATE); 
SharedPreferences.Editor editor = sp.edit(); 
if (object instanceof String) 
{ 
editor.putString(key, (String) object); 
} else if (object instanceof Integer) 
{ 
editor.putInt(key, (Integer) object); 
} else if (object instanceof Boolean) 
{ 
editor.putBoolean(key, (Boolean) object); 
} else if (object instanceof Float) 
{ 
editor.putFloat(key, (Float) object); 
} else if (object instanceof Long) 
{ 
editor.putLong(key, (Long) object); 
} else 
{ 
editor.putString(key, object.toString()); 
} 
SharedPreferencesCompat.apply(editor); 
} 
/** 
* 得到保存數據的方法，我們根據默認值得到保存的數據的具體類型，然後調用相對於的方法獲取值 
* 
* @param context 
* @param key 
* @param defaultObject 
* @return 
*/ 
public static Object get(Context context, String key, Object defaultObject) 
{ 
SharedPreferences sp = context.getSharedPreferences(FILE_NAME, 
Context.MODE_PRIVATE); 
if (defaultObject instanceof String) 
{ 
return sp.getString(key, (String) defaultObject); 
} else if (defaultObject instanceof Integer) 
{ 
return sp.getInt(key, (Integer) defaultObject); 
} else if (defaultObject instanceof Boolean) 
{ 
return sp.getBoolean(key, (Boolean) defaultObject); 
} else if (defaultObject instanceof Float) 
{ 
return sp.getFloat(key, (Float) defaultObject); 
} else if (defaultObject instanceof Long) 
{ 
return sp.getLong(key, (Long) defaultObject); 
} 
return null; 
} 
/** 
* 移除某個key值已經對應的值 
* @param context 
* @param key 
*/ 
public static void remove(Context context, String key) 
{ 
SharedPreferences sp = context.getSharedPreferences(FILE_NAME, 
Context.MODE_PRIVATE); 
SharedPreferences.Editor editor = sp.edit(); 
editor.remove(key); 
SharedPreferencesCompat.apply(editor); 
} 
/** 
* 清除所有數據 
* @param context 
*/ 
public static void clear(Context context) 
{ 
SharedPreferences sp = context.getSharedPreferences(FILE_NAME, 
Context.MODE_PRIVATE); 
SharedPreferences.Editor editor = sp.edit(); 
editor.clear(); 
SharedPreferencesCompat.apply(editor); 
} 
/** 
* 查詢某個key是否已經存在 
* @param context 
* @param key 
* @return 
*/ 
public static boolean contains(Context context, String key) 
{ 
SharedPreferences sp = context.getSharedPreferences(FILE_NAME, 
Context.MODE_PRIVATE); 
return sp.contains(key); 
} 
/** 
* 返回所有的鍵值對 
* 
* @param context 
* @return 
*/ 
public static Map<String, ?> getAll(Context context) 
{ 
SharedPreferences sp = context.getSharedPreferences(FILE_NAME, 
Context.MODE_PRIVATE); 
return sp.getAll(); 
} 
/** 
* 創建一個解決SharedPreferencesCompat.apply方法的一個兼容類 
* 
* @author zhy 
* 
*/ 
private static class SharedPreferencesCompat 
{ 
private static final Method sApplyMethod = findApplyMethod(); 
/** 
* 反射查找apply的方法 
* 
* @return 
*/ 
@SuppressWarnings({ "unchecked", "rawtypes" }) 
private static Method findApplyMethod() 
{ 
try 
{ 
Class clz = SharedPreferences.Editor.class; 
return clz.getMethod("apply"); 
} catch (NoSuchMethodException e) 
{ 
} 
return null; 
} 
/** 
* 如果找到則使用apply執行，否則使用commit 
* 
* @param editor 
*/ 
public static void apply(SharedPreferences.Editor editor) 
{ 
try 
{ 
if (sApplyMethod != null) 
{ 
sApplyMethod.invoke(editor); 
return; 
} 
} catch (IllegalArgumentException e) 
{ 
} catch (IllegalAccessException e) 
{ 
} catch (InvocationTargetException e) 
{ 
} 
editor.commit(); 
} 
} 
}

對SharedPreference的使用做了建議的封裝，對外公布出put，get，remove，clear等等方法；

注意一點，裡面所有的commit操作使用了SharedPreferencesCompat.apply進行了替代，目的是盡可能的使用apply代替commit.
首先說下為什麼，因為commit方法是同步的，並且我們很多時候的commit操作都是UI線程中，畢竟是IO操作，盡可能異步；
所以我們使用apply進行替代，apply異步的進行寫入；
但是apply相當於commit來說是new API呢，為了更好的兼容，我們做了適配；
SharedPreferencesCompat也可以給大家創建兼容類提供了一定的參考

2. SPUtils.java

public class PreferencesUtils {
public static String PREFERENCE_NAME = "TrineaAndroidCommon";
private PreferencesUtils() {
throw new AssertionError();
}
/**
* put string preferences
* 
* @param context
* @param key The name of the preference to modify
* @param value The new value for the preference
* @return True if the new values were successfully written to persistent storage.
*/
public static boolean putString(Context context, String key, String value) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = settings.edit();
editor.putString(key, value);
return editor.commit();
}
/**
* get string preferences
* 
* @param context
* @param key The name of the preference to retrieve
* @return The preference value if it exists, or null. Throws ClassCastException if there is a preference with this
* name that is not a string
* @see #getString(Context, String, String)
*/
public static String getString(Context context, String key) {
return getString(context, key, null);
}
/**
* get string preferences
* 
* @param context
* @param key The name of the preference to retrieve
* @param defaultValue Value to return if this preference does not exist
* @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with
* this name that is not a string
*/
public static String getString(Context context, String key, String defaultValue) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
return settings.getString(key, defaultValue);
}
/**
* put int preferences
* 
* @param context
* @param key The name of the preference to modify
* @param value The new value for the preference
* @return True if the new values were successfully written to persistent storage.
*/
public static boolean putInt(Context context, String key, int value) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = settings.edit();
editor.putInt(key, value);
return editor.commit();
}
/**
* get int preferences
* 
* @param context
* @param key The name of the preference to retrieve
* @return The preference value if it exists, or -. Throws ClassCastException if there is a preference with this
* name that is not a int
* @see #getInt(Context, String, int)
*/
public static int getInt(Context context, String key) {
return getInt(context, key, -);
}
/**
* get int preferences
* 
* @param context
* @param key The name of the preference to retrieve
* @param defaultValue Value to return if this preference does not exist
* @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with
* this name that is not a int
*/
public static int getInt(Context context, String key, int defaultValue) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
return settings.getInt(key, defaultValue);
}
/**
* put long preferences
* 
* @param context
* @param key The name of the preference to modify
* @param value The new value for the preference
* @return True if the new values were successfully written to persistent storage.
*/
public static boolean putLong(Context context, String key, long value) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = settings.edit();
editor.putLong(key, value);
return editor.commit();
}
/**
* get long preferences
* 
* @param context
* @param key The name of the preference to retrieve
* @return The preference value if it exists, or -. Throws ClassCastException if there is a preference with this
* name that is not a long
* @see #getLong(Context, String, long)
*/
public static long getLong(Context context, String key) {
return getLong(context, key, -);
}
/**
* get long preferences
* 
* @param context
* @param key The name of the preference to retrieve
* @param defaultValue Value to return if this preference does not exist
* @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with
* this name that is not a long
*/
public static long getLong(Context context, String key, long defaultValue) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
return settings.getLong(key, defaultValue);
}
/**
* put float preferences
* 
* @param context
* @param key The name of the preference to modify
* @param value The new value for the preference
* @return True if the new values were successfully written to persistent storage.
*/
public static boolean putFloat(Context context, String key, float value) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = settings.edit();
editor.putFloat(key, value);
return editor.commit();
}
/**
* get float preferences
* 
* @param context
* @param key The name of the preference to retrieve
* @return The preference value if it exists, or -. Throws ClassCastException if there is a preference with this
* name that is not a float
* @see #getFloat(Context, String, float)
*/
public static float getFloat(Context context, String key) {
return getFloat(context, key, -);
}
/**
* get float preferences
* 
* @param context
* @param key The name of the preference to retrieve
* @param defaultValue Value to return if this preference does not exist
* @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with
* this name that is not a float
*/
public static float getFloat(Context context, String key, float defaultValue) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
return settings.getFloat(key, defaultValue);
}
/**
* put boolean preferences
* 
* @param context
* @param key The name of the preference to modify
* @param value The new value for the preference
* @return True if the new values were successfully written to persistent storage.
*/
public static boolean putBoolean(Context context, String key, boolean value) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = settings.edit();
editor.putBoolean(key, value);
return editor.commit();
}
/**
* get boolean preferences, default is false
* 
* @param context
* @param key The name of the preference to retrieve
* @return The preference value if it exists, or false. Throws ClassCastException if there is a preference with this
* name that is not a boolean
* @see #getBoolean(Context, String, boolean)
*/
public static boolean getBoolean(Context context, String key) {
return getBoolean(context, key, false);
}
/**
* get boolean preferences
* 
* @param context
* @param key The name of the preference to retrieve
* @param defaultValue Value to return if this preference does not exist
* @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with
* this name that is not a boolean
*/
public static boolean getBoolean(Context context, String key, boolean defaultValue) {
SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
return settings.getBoolean(key, defaultValue);
}
}

四、單位轉換類 DensityUtils.java

public class DensityUtils 
{ 
private DensityUtils() 
{ 
/* cannot be instantiated */ 
throw new UnsupportedOperationException("cannot be instantiated"); 
} 
/** 
* dp轉px 
* 
* @param context 
* @param val 
* @return 
*/ 
public static int dppx(Context context, float dpVal) 
{ 
return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 
dpVal, context.getResources().getDisplayMetrics()); 
} 
/** 
* sp轉px 
* 
* @param context 
* @param val 
* @return 
*/ 
public static int sppx(Context context, float spVal) 
{ 
return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, 
spVal, context.getResources().getDisplayMetrics()); 
} 
/** 
* px轉dp 
* 
* @param context 
* @param pxVal 
* @return 
*/ 
public static float pxdp(Context context, float pxVal) 
{ 
final float scale = context.getResources().getDisplayMetrics().density; 
return (pxVal / scale); 
} 
/** 
* px轉sp 
* 
* @param fontScale 
* @param pxVal 
* @return 
*/ 
public static float pxsp(Context context, float pxVal) 
{ 
return (pxVal / context.getResources().getDisplayMetrics().scaledDensity); 
} 
}

TypedValue：

Container for a dynamically typed data value. Primarily used with Resources for holding resource values.
applyDimension(int unit, float value, DisplayMetrics metrics)：
Converts an unpacked complex data value holding a dimension to its final floating point value.

五、SD卡相關輔助類 SDCardUtils.java

public class SDCardUtils 
{ 
private SDCardUtils() 
{ 
/* cannot be instantiated */ 
throw new UnsupportedOperationException("cannot be instantiated"); 
} 
/** 
* 判斷SDCard是否可用 
* 
* @return 
*/ 
public static boolean isSDCardEnable() 
{ 
return Environment.getExternalStorageState().equals( 
Environment.MEDIA_MOUNTED); 
} 
/** 
* 獲取SD卡路徑 
* 
* @return 
*/ 
public static String getSDCardPath() 
{ 
return Environment.getExternalStorageDirectory().getAbsolutePath() 
+ File.separator; 
} 
/** 
* 獲取SD卡的剩余容量 單位byte 
* 
* @return 
*/ 
public static long getSDCardAllSize() 
{ 
if (isSDCardEnable()) 
{ 
StatFs stat = new StatFs(getSDCardPath()); 
// 獲取空閒的數據塊的數量 
long availableBlocks = (long) stat.getAvailableBlocks() - ; 
// 獲取單個數據塊的大小（byte） 
long freeBlocks = stat.getAvailableBlocks(); 
return freeBlocks * availableBlocks; 
} 
return ; 
} 
/** 
* 獲取指定路徑所在空間的剩余可用容量字節數，單位byte 
* 
* @param filePath 
* @return 容量字節 SDCard可用空間，內部存儲可用空間 
*/ 
public static long getFreeBytes(String filePath) 
{ 
// 如果是sd卡的下的路徑，則獲取sd卡可用容量 
if (filePath.startsWith(getSDCardPath())) 
{ 
filePath = getSDCardPath(); 
} else 
{// 如果是內部存儲的路徑，則獲取內存存儲的可用容量 
filePath = Environment.getDataDirectory().getAbsolutePath(); 
} 
StatFs stat = new StatFs(filePath); 
long availableBlocks = (long) stat.getAvailableBlocks() - ; 
return stat.getBlockSize() * availableBlocks; 
} 
/** 
* 獲取系統存儲路徑 
* 
* @return 
*/ 
public static String getRootDirectoryPath() 
{ 
return Environment.getRootDirectory().getAbsolutePath(); 
} 
}

StatFs 是Android提供的一個類：

Retrieve overall information about the space on a filesystem. This is a wrapper for Unix statvfs().

檢索一個文件系統的整體信息空間。這是一個Unix statvfs() 包裝器

六、屏幕相關輔助類 ScreenUtils.java

public class ScreenUtils 
{ 
private ScreenUtils() 
{ 
/* cannot be instantiated */ 
throw new UnsupportedOperationException("cannot be instantiated"); 
} 
/** 
* 獲得屏幕高度 
* 
* @param context 
* @return 
*/ 
public static int getScreenWidth(Context context) 
{ 
WindowManager wm = (WindowManager) context 
.getSystemService(Context.WINDOW_SERVICE); 
DisplayMetrics outMetrics = new DisplayMetrics(); 
wm.getDefaultDisplay().getMetrics(outMetrics); 
return outMetrics.widthPixels; 
} 
/** 
* 獲得屏幕寬度 
* 
* @param context 
* @return 
*/ 
public static int getScreenHeight(Context context) 
{ 
WindowManager wm = (WindowManager) context 
.getSystemService(Context.WINDOW_SERVICE); 
DisplayMetrics outMetrics = new DisplayMetrics(); 
wm.getDefaultDisplay().getMetrics(outMetrics); 
return outMetrics.heightPixels; 
} 
/** 
* 獲得狀態欄的高度 
* 
* @param context 
* @return 
*/ 
public static int getStatusHeight(Context context) 
{ 
int statusHeight = -; 
try 
{ 
Class<?> clazz = Class.forName("com.android.internal.R$dimen"); 
Object object = clazz.newInstance(); 
int height = Integer.parseInt(clazz.getField("status_bar_height") 
.get(object).toString()); 
statusHeight = context.getResources().getDimensionPixelSize(height); 
} catch (Exception e) 
{ 
e.printStackTrace(); 
} 
return statusHeight; 
} 
/** 
* 獲取當前屏幕截圖，包含狀態欄 
* 
* @param activity 
* @return 
*/ 
public static Bitmap snapShotWithStatusBar(Activity activity) 
{ 
View view = activity.getWindow().getDecorView(); 
view.setDrawingCacheEnabled(true); 
view.buildDrawingCache(); 
Bitmap bmp = view.getDrawingCache(); 
int width = getScreenWidth(activity); 
int height = getScreenHeight(activity); 
Bitmap bp = null; 
bp = Bitmap.createBitmap(bmp, , , width, height); 
view.destroyDrawingCache(); 
return bp; 
} 
/** 
* 獲取當前屏幕截圖，不包含狀態欄 
* 
* @param activity 
* @return 
*/ 
public static Bitmap snapShotWithoutStatusBar(Activity activity) 
{ 
View view = activity.getWindow().getDecorView(); 
view.setDrawingCacheEnabled(true); 
view.buildDrawingCache(); 
Bitmap bmp = view.getDrawingCache(); 
Rect frame = new Rect(); 
activity.getWindow().getDecorView().getWindowVisibleDisplayFrame(frame); 
int statusBarHeight = frame.top; 
int width = getScreenWidth(activity); 
int height = getScreenHeight(activity); 
Bitmap bp = null; 
bp = Bitmap.createBitmap(bmp, , statusBarHeight, width, height 
- statusBarHeight); 
view.destroyDrawingCache(); 
return bp; 
} 
}

七、App相關輔助類 APPUtils.java

public class AppUtils 
{ 
private AppUtils() 
{ 
/* cannot be instantiated */ 
throw new UnsupportedOperationException("cannot be instantiated"); 
} 
/** 
* 獲取應用程序名稱 
*/ 
public static String getAppName(Context context) 
{ 
try 
{ 
PackageManager packageManager = context.getPackageManager(); 
PackageInfo packageInfo = packageManager.getPackageInfo( 
context.getPackageName(), ); 
int labelRes = packageInfo.applicationInfo.labelRes; 
return context.getResources().getString(labelRes); 
} catch (NameNotFoundException e) 
{ 
e.printStackTrace(); 
} 
return null; 
} 
/** 
* [獲取應用程序版本名稱信息] 
* 
* @param context 
* @return 當前應用的版本名稱 
*/ 
public static String getVersionName(Context context) 
{ 
try 
{ 
PackageManager packageManager = context.getPackageManager(); 
PackageInfo packageInfo = packageManager.getPackageInfo( 
context.getPackageName(), ); 
return packageInfo.versionName; 
} catch (NameNotFoundException e) 
{ 
e.printStackTrace(); 
} 
return null; 
} 
}

八、軟鍵盤相關輔助類KeyBoardUtils.java

/** 
* 打開或關閉軟鍵盤 
*/ 
public class KeyBoardUtils 
{ 
/** 
* 打卡軟鍵盤 
* 
* @param mEditText 輸入框 
* @param mContext 上下文 
*/ 
public static void openKeybord(EditText mEditText, Context mContext) 
{ 
InputMethodManager imm = (InputMethodManager) mContext 
.getSystemService(Context.INPUT_METHOD_SERVICE); 
imm.showSoftInput(mEditText, InputMethodManager.RESULT_SHOWN); 
imm.toggleSoftInput(InputMethodManager.SHOW_FORCED, 
InputMethodManager.HIDE_IMPLICIT_ONLY); 
} 
/** 
* 關閉軟鍵盤 
* 
* @param mEditText 輸入框 
* @param mContext 上下文 
*/ 
public static void closeKeybord(EditText mEditText, Context mContext) 
{ 
InputMethodManager imm = (InputMethodManager) mContext 
.getSystemService(Context.INPUT_METHOD_SERVICE); 
imm.hideSoftInputFromWindow(mEditText.getWindowToken(), ); 
} 
}

九、網絡相關輔助類 NetUtils.java

public class NetUtils 
{ 
private NetUtils() 
{ 
/* cannot be instantiated */ 
throw new UnsupportedOperationException("cannot be instantiated"); 
} 
/** 
* 判斷網絡是否連接 
*/ 
public static boolean isConnected(Context context) 
{ 
ConnectivityManager connectivity = (ConnectivityManager) context 
.getSystemService(Context.CONNECTIVITY_SERVICE); 
if (null != connectivity) 
{ 
NetworkInfo info = connectivity.getActiveNetworkInfo(); 
if (null != info && info.isConnected()) 
{ 
if (info.getState() == NetworkInfo.State.CONNECTED) 
{ 
return true; 
} 
} 
} 
return false; 
} 
/** 
* 判斷是否是wifi連接 
*/ 
public static boolean isWifi(Context context) 
{ 
ConnectivityManager cm = (ConnectivityManager) context 
.getSystemService(Context.CONNECTIVITY_SERVICE); 
if (cm == null) 
return false; 
return cm.getActiveNetworkInfo().getType() == ConnectivityManager.TYPE_WIFI; 
} 
/** 
* 打開網絡設置界面 
*/ 
public static void openSetting(Activity activity) 
{ 
Intent intent = new Intent("/"); 
ComponentName cm = new ComponentName("com.android.settings", 
"com.android.settings.WirelessSettings"); 
intent.setComponent(cm); 
intent.setAction("android.intent.action.VIEW"); 
activity.startActivityForResult(intent, ); 
} 
}

十、Http相關輔助類 HttpUtils.java

/** 
* Http請求的工具類 
*/
public class HttpUtils 
{ 
private static final int TIMEOUT_IN_MILLIONS = ; 
public interface CallBack 
{ 
void onRequestComplete(String result); 
} 
/** 
* 異步的Get請求 
* 
* @param urlStr 
* @param callBack 
*/ 
public static void doGetAsyn(final String urlStr, final CallBack callBack) 
{ 
new Thread() 
{ 
public void run() 
{ 
try 
{ 
String result = doGet(urlStr); 
if (callBack != null) 
{ 
callBack.onRequestComplete(result); 
} 
} catch (Exception e) 
{ 
e.printStackTrace(); 
} 
}; 
}.start(); 
} 
/** 
* 異步的Post請求 
* @param urlStr 
* @param params 
* @param callBack 
* @throws Exception 
*/ 
public static void doPostAsyn(final String urlStr, final String params, 
final CallBack callBack) throws Exception 
{ 
new Thread() 
{ 
public void run() 
{ 
try 
{ 
String result = doPost(urlStr, params); 
if (callBack != null) 
{ 
callBack.onRequestComplete(result); 
} 
} catch (Exception e) 
{ 
e.printStackTrace(); 
} 
}; 
}.start(); 
} 
/** 
* Get請求，獲得返回數據 
* 
* @param urlStr 
* @return 
* @throws Exception 
*/ 
public static String doGet(String urlStr) 
{ 
URL url = null; 
HttpURLConnection conn = null; 
InputStream is = null; 
ByteArrayOutputStream baos = null; 
try 
{ 
url = new URL(urlStr); 
conn = (HttpURLConnection) url.openConnection(); 
conn.setReadTimeout(TIMEOUT_IN_MILLIONS); 
conn.setConnectTimeout(TIMEOUT_IN_MILLIONS); 
conn.setRequestMethod("GET"); 
conn.setRequestProperty("accept", "*/*"); 
conn.setRequestProperty("connection", "Keep-Alive"); 
if (conn.getResponseCode() == ) 
{ 
is = conn.getInputStream(); 
baos = new ByteArrayOutputStream(); 
int len = -; 
byte[] buf = new byte[]; 
while ((len = is.read(buf)) != -) 
{ 
baos.write(buf, , len); 
} 
baos.flush(); 
return baos.toString(); 
} else 
{ 
throw new RuntimeException(" responseCode is not ... "); 
} 
} catch (Exception e) 
{ 
e.printStackTrace(); 
} finally 
{ 
try 
{ 
if (is != null) 
is.close(); 
} catch (IOException e) 
{ 
} 
try 
{ 
if (baos != null) 
baos.close(); 
} catch (IOException e) 
{ 
} 
conn.disconnect(); 
} 
return null ; 
} 
/** 
* 向指定 URL 發送POST方法的請求 
* 
* @param url 
* 發送請求的 URL 
* @param param 
* 請求參數，請求參數應該是 name=value&name=value 的形式。 
* @return 所代表遠程資源的響應結果 
* @throws Exception 
*/ 
public static String doPost(String url, String param) 
{ 
PrintWriter out = null; 
BufferedReader in = null; 
String result = ""; 
try 
{ 
URL realUrl = new URL(url); 
// 打開和URL之間的連接 
HttpURLConnection conn = (HttpURLConnection) realUrl 
.openConnection(); 
// 設置通用的請求屬性 
conn.setRequestProperty("accept", "*/*"); 
conn.setRequestProperty("connection", "Keep-Alive"); 
conn.setRequestMethod("POST"); 
conn.setRequestProperty("Content-Type", 
"application/x-www-form-urlencoded"); 
conn.setRequestProperty("charset", "utf-"); 
conn.setUseCaches(false); 
// 發送POST請求必須設置如下兩行 
conn.setDoOutput(true); 
conn.setDoInput(true); 
conn.setReadTimeout(TIMEOUT_IN_MILLIONS); 
conn.setConnectTimeout(TIMEOUT_IN_MILLIONS); 
if (param != null && !param.trim().equals("")) 
{ 
// 獲取URLConnection對象對應的輸出流 
out = new PrintWriter(conn.getOutputStream()); 
// 發送請求參數 
out.print(param); 
// flush輸出流的緩沖 
out.flush(); 
} 
// 定義BufferedReader輸入流來讀取URL的響應 
in = new BufferedReader( 
new InputStreamReader(conn.getInputStream())); 
String line; 
while ((line = in.readLine()) != null) 
{ 
result += line; 
} 
} catch (Exception e) 
{ 
e.printStackTrace(); 
} 
// 使用finally塊來關閉輸出流、輸入流 
finally 
{ 
try 
{ 
if (out != null) 
{ 
out.close(); 
} 
if (in != null) 
{ 
in.close(); 
} 
} catch (IOException ex) 
{ 
ex.printStackTrace(); 
} 
} 
return result; 
} 
}

十一、時間工具類 TimeUtils.java

public class TimeUtils {
public static final SimpleDateFormat DEFAULT_DATE_FORMAT = 
new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
public static final SimpleDateFormat DATE_FORMAT_DATE = 
new SimpleDateFormat("yyyy-MM-dd");
private TimeUtils() {
throw new AssertionError();
}
/**
* long time to string
* 
* @param timeInMillis
* @param dateFormat
* @return
*/
public static String getTime(long timeInMillis, SimpleDateFormat dateFormat) {
return dateFormat.format(new Date(timeInMillis));
}
/**
* long time to string, format is {@link #DEFAULT_DATE_FORMAT}
* 
* @param timeInMillis
* @return
*/
public static String getTime(long timeInMillis) {
return getTime(timeInMillis, DEFAULT_DATE_FORMAT);
}
/**
* get current time in milliseconds
* 
* @return
*/
public static long getCurrentTimeInLong() {
return System.currentTimeMillis();
}
/**
* get current time in milliseconds, format is {@link #DEFAULT_DATE_FORMAT}
* 
* @return
*/
public static String getCurrentTimeInString() {
return getTime(getCurrentTimeInLong());
}
/**
* get current time in milliseconds
* 
* @return
*/
public static String getCurrentTimeInString(SimpleDateFormat dateFormat) {
return getTime(getCurrentTimeInLong(), dateFormat);
}
}

十二、文件工具類 FileUtils.java

public class FileUtils {
public final static String FILE_EXTENSION_SEPARATOR = ".";
private FileUtils() {
throw new AssertionError();
}
/**
* read file
* 
* @param filePath
* @param charsetName The name of a supported {@link java.nio.charset.Charset </code>charset<code>}
* @return if file not exist, return null, else return content of file
* @throws RuntimeException if an error occurs while operator BufferedReader
*/
public static StringBuilder readFile(String filePath, String charsetName) {
File file = new File(filePath);
StringBuilder fileContent = new StringBuilder("");
if (file == null || !file.isFile()) {
return null;
}
BufferedReader reader = null;
try {
InputStreamReader is = new InputStreamReader(new FileInputStream(file), charsetName);
reader = new BufferedReader(is);
String line = null;
while ((line = reader.readLine()) != null) {
if (!fileContent.toString().equals("")) {
fileContent.append("\r\n");
}
fileContent.append(line);
}
return fileContent;
} catch (IOException e) {
throw new RuntimeException("IOException occurred. ", e);
} finally {
IOUtils.close(reader);
}
}
/**
* write file
* 
* @param filePath
* @param content
* @param append is append, if true, write to the end of file, else clear content of file and write into it
* @return return false if content is empty, true otherwise
* @throws RuntimeException if an error occurs while operator FileWriter
*/
public static boolean writeFile(String filePath, String content, boolean append) {
if (StringUtils.isEmpty(content)) {
return false;
}
FileWriter fileWriter = null;
try {
makeDirs(filePath);
fileWriter = new FileWriter(filePath, append);
fileWriter.write(content);
return true;
} catch (IOException e) {
throw new RuntimeException("IOException occurred. ", e);
} finally {
IOUtils.close(fileWriter);
}
}
/**
* write file
* 
* @param filePath
* @param contentList
* @param append is append, if true, write to the end of file, else clear content of file and write into it
* @return return false if contentList is empty, true otherwise
* @throws RuntimeException if an error occurs while operator FileWriter
*/
public static boolean writeFile(String filePath, List<String> contentList, boolean append) {
if (ListUtils.isEmpty(contentList)) {
return false;
}
FileWriter fileWriter = null;
try {
makeDirs(filePath);
fileWriter = new FileWriter(filePath, append);
int i = ;
for (String line : contentList) {
if (i++ > ) {
fileWriter.write("\r\n");
}
fileWriter.write(line);
}
return true;
} catch (IOException e) {
throw new RuntimeException("IOException occurred. ", e);
} finally {
IOUtils.close(fileWriter);
}
}
/**
* write file, the string will be written to the begin of the file
* 
* @param filePath
* @param content
* @return
*/
public static boolean writeFile(String filePath, String content) {
return writeFile(filePath, content, false);
}
/**
* write file, the string list will be written to the begin of the file
* 
* @param filePath
* @param contentList
* @return
*/
public static boolean writeFile(String filePath, List<String> contentList) {
return writeFile(filePath, contentList, false);
}
/**
* write file, the bytes will be written to the begin of the file
* 
* @param filePath
* @param stream
* @return
* @see {@link #writeFile(String, InputStream, boolean)}
*/
public static boolean writeFile(String filePath, InputStream stream) {
return writeFile(filePath, stream, false);
}
/**
* write file
* 
* @param file the file to be opened for writing.
* @param stream the input stream
* @param append if <code>true</code>, then bytes will be written to the end of the file rather than the beginning
* @return return true
* @throws RuntimeException if an error occurs while operator FileOutputStream
*/
public static boolean writeFile(String filePath, InputStream stream, boolean append) {
return writeFile(filePath != null ? new File(filePath) : null, stream, append);
}
/**
* write file, the bytes will be written to the begin of the file
* 
* @param file
* @param stream
* @return
* @see {@link #writeFile(File, InputStream, boolean)}
*/
public static boolean writeFile(File file, InputStream stream) {
return writeFile(file, stream, false);
}
/**
* write file
* 
* @param file the file to be opened for writing.
* @param stream the input stream
* @param append if <code>true</code>, then bytes will be written to the end of the file rather than the beginning
* @return return true
* @throws RuntimeException if an error occurs while operator FileOutputStream
*/
public static boolean writeFile(File file, InputStream stream, boolean append) {
OutputStream o = null;
try {
makeDirs(file.getAbsolutePath());
o = new FileOutputStream(file, append);
byte data[] = new byte[];
int length = -;
while ((length = stream.read(data)) != -) {
o.write(data, , length);
}
o.flush();
return true;
} catch (FileNotFoundException e) {
throw new RuntimeException("FileNotFoundException occurred. ", e);
} catch (IOException e) {
throw new RuntimeException("IOException occurred. ", e);
} finally {
IOUtils.close(o);
IOUtils.close(stream);
}
}
/**
* move file
* 
* @param sourceFilePath
* @param destFilePath
*/
public static void moveFile(String sourceFilePath, String destFilePath) {
if (TextUtils.isEmpty(sourceFilePath) || TextUtils.isEmpty(destFilePath)) {
throw new RuntimeException("Both sourceFilePath and destFilePath cannot be null.");
}
moveFile(new File(sourceFilePath), new File(destFilePath));
}
/**
* move file
* 
* @param srcFile
* @param destFile
*/
public static void moveFile(File srcFile, File destFile) {
boolean rename = srcFile.renameTo(destFile);
if (!rename) {
copyFile(srcFile.getAbsolutePath(), destFile.getAbsolutePath());
deleteFile(srcFile.getAbsolutePath());
}
}
/**
* copy file
* 
* @param sourceFilePath
* @param destFilePath
* @return
* @throws RuntimeException if an error occurs while operator FileOutputStream
*/
public static boolean copyFile(String sourceFilePath, String destFilePath) {
InputStream inputStream = null;
try {
inputStream = new FileInputStream(sourceFilePath);
} catch (FileNotFoundException e) {
throw new RuntimeException("FileNotFoundException occurred. ", e);
}
return writeFile(destFilePath, inputStream);
}
/**
* read file to string list, a element of list is a line
* 
* @param filePath
* @param charsetName The name of a supported {@link java.nio.charset.Charset </code>charset<code>}
* @return if file not exist, return null, else return content of file
* @throws RuntimeException if an error occurs while operator BufferedReader
*/
public static List<String> readFileToList(String filePath, String charsetName) {
File file = new File(filePath);
List<String> fileContent = new ArrayList<String>();
if (file == null || !file.isFile()) {
return null;
}
BufferedReader reader = null;
try {
InputStreamReader is = new InputStreamReader(new FileInputStream(file), charsetName);
reader = new BufferedReader(is);
String line = null;
while ((line = reader.readLine()) != null) {
fileContent.add(line);
}
return fileContent;
} catch (IOException e) {
throw new RuntimeException("IOException occurred. ", e);
} finally {
IOUtils.close(reader);
}
}
/**
* get file name from path, not include suffix
* 
* <pre>
* getFileNameWithoutExtension(null) = null
* getFileNameWithoutExtension("") = ""
* getFileNameWithoutExtension(" ") = " "
* getFileNameWithoutExtension("abc") = "abc"
* getFileNameWithoutExtension("a.mp") = "a"
* getFileNameWithoutExtension("a.b.rmvb") = "a.b"
* getFileNameWithoutExtension("c:\\") = ""
* getFileNameWithoutExtension("c:\\a") = "a"
* getFileNameWithoutExtension("c:\\a.b") = "a"
* getFileNameWithoutExtension("c:a.txt\\a") = "a"
* getFileNameWithoutExtension("/home/admin") = "admin"
* getFileNameWithoutExtension("/home/admin/a.txt/b.mp") = "b"
* </pre>
* 
* @param filePath
* @return file name from path, not include suffix
* @see
*/
public static String getFileNameWithoutExtension(String filePath) {
if (StringUtils.isEmpty(filePath)) {
return filePath;
}
int extenPosi = filePath.lastIndexOf(FILE_EXTENSION_SEPARATOR);
int filePosi = filePath.lastIndexOf(File.separator);
if (filePosi == -) {
return (extenPosi == - ? filePath : filePath.substring(, extenPosi));
}
if (extenPosi == -) {
return filePath.substring(filePosi + );
}
return (filePosi < extenPosi ? filePath.substring(filePosi + , extenPosi) : filePath.substring(filePosi + ));
}
/**
* get file name from path, include suffix
* 
* <pre>
* getFileName(null) = null
* getFileName("") = ""
* getFileName(" ") = " "
* getFileName("a.mp") = "a.mp"
* getFileName("a.b.rmvb") = "a.b.rmvb"
* getFileName("abc") = "abc"
* getFileName("c:\\") = ""
* getFileName("c:\\a") = "a"
* getFileName("c:\\a.b") = "a.b"
* getFileName("c:a.txt\\a") = "a"
* getFileName("/home/admin") = "admin"
* getFileName("/home/admin/a.txt/b.mp") = "b.mp"
* </pre>
* 
* @param filePath
* @return file name from path, include suffix
*/
public static String getFileName(String filePath) {
if (StringUtils.isEmpty(filePath)) {
return filePath;
}
int filePosi = filePath.lastIndexOf(File.separator);
return (filePosi == -) ? filePath : filePath.substring(filePosi + );
}
/**
* get folder name from path
* 
* <pre>
* getFolderName(null) = null
* getFolderName("") = ""
* getFolderName(" ") = ""
* getFolderName("a.mp") = ""
* getFolderName("a.b.rmvb") = ""
* getFolderName("abc") = ""
* getFolderName("c:\\") = "c:"
* getFolderName("c:\\a") = "c:"
* getFolderName("c:\\a.b") = "c:"
* getFolderName("c:a.txt\\a") = "c:a.txt"
* getFolderName("c:a\\b\\c\\d.txt") = "c:a\\b\\c"
* getFolderName("/home/admin") = "/home"
* getFolderName("/home/admin/a.txt/b.mp") = "/home/admin/a.txt"
* </pre>
* 
* @param filePath
* @return
*/
public static String getFolderName(String filePath) {
if (StringUtils.isEmpty(filePath)) {
return filePath;
}
int filePosi = filePath.lastIndexOf(File.separator);
return (filePosi == -) ? "" : filePath.substring(, filePosi);
}
/**
* get suffix of file from path
* 
* <pre>
* getFileExtension(null) = ""
* getFileExtension("") = ""
* getFileExtension(" ") = " "
* getFileExtension("a.mp") = "mp"
* getFileExtension("a.b.rmvb") = "rmvb"
* getFileExtension("abc") = ""
* getFileExtension("c:\\") = ""
* getFileExtension("c:\\a") = ""
* getFileExtension("c:\\a.b") = "b"
* getFileExtension("c:a.txt\\a") = ""
* getFileExtension("/home/admin") = ""
* getFileExtension("/home/admin/a.txt/b") = ""
* getFileExtension("/home/admin/a.txt/b.mp") = "mp"
* </pre>
* 
* @param filePath
* @return
*/
public static String getFileExtension(String filePath) {
if (StringUtils.isBlank(filePath)) {
return filePath;
}
int extenPosi = filePath.lastIndexOf(FILE_EXTENSION_SEPARATOR);
int filePosi = filePath.lastIndexOf(File.separator);
if (extenPosi == -) {
return "";
}
return (filePosi >= extenPosi) ? "" : filePath.substring(extenPosi + );
}
/**
* Creates the directory named by the trailing filename of this file, including the complete directory path required
* to create this directory. <br/>
* <br/>
* <ul>
* <strong>Attentions:</strong>
* <li>makeDirs("C:\\Users\\Trinea") can only create users folder</li>
* <li>makeFolder("C:\\Users\\Trinea\\") can create Trinea folder</li>
* </ul>
* 
* @param filePath
* @return true if the necessary directories have been created or the target directory already exists, false one of
* the directories can not be created.
* <ul>
* <li>if {@link FileUtils#getFolderName(String)} return null, return false</li>
* <li>if target directory already exists, return true</li>
* <li>return {@link java.io.File#makeFolder}</li>
* </ul>
*/
public static boolean makeDirs(String filePath) {
String folderName = getFolderName(filePath);
if (StringUtils.isEmpty(folderName)) {
return false;
}
File folder = new File(folderName);
return (folder.exists() && folder.isDirectory()) ? true : folder.mkdirs();
}
/**
* @param filePath
* @return
* @see #makeDirs(String)
*/
public static boolean makeFolders(String filePath) {
return makeDirs(filePath);
}
/**
* Indicates if this file represents a file on the underlying file system.
* 
* @param filePath
* @return
*/
public static boolean isFileExist(String filePath) {
if (StringUtils.isBlank(filePath)) {
return false;
}
File file = new File(filePath);
return (file.exists() && file.isFile());
}
/**
* Indicates if this file represents a directory on the underlying file system.
* 
* @param directoryPath
* @return
*/
public static boolean isFolderExist(String directoryPath) {
if (StringUtils.isBlank(directoryPath)) {
return false;
}
File dire = new File(directoryPath);
return (dire.exists() && dire.isDirectory());
}
/**
* delete file or directory
* <ul>
* <li>if path is null or empty, return true</li>
* <li>if path not exist, return true</li>
* <li>if path exist, delete recursion. return true</li>
* <ul>
* 
* @param path
* @return
*/
public static boolean deleteFile(String path) {
if (StringUtils.isBlank(path)) {
return true;
}
File file = new File(path);
if (!file.exists()) {
return true;
}
if (file.isFile()) {
return file.delete();
}
if (!file.isDirectory()) {
return false;
}
for (File f : file.listFiles()) {
if (f.isFile()) {
f.delete();
} else if (f.isDirectory()) {
deleteFile(f.getAbsolutePath());
}
}
return file.delete();
}
/**
* get file size
* <ul>
* <li>if path is null or empty, return -</li>
* <li>if path exist and it is a file, return file size, else return -</li>
* <ul>
* 
* @param path
* @return returns the length of this file in bytes. returns - if the file does not exist.
*/
public static long getFileSize(String path) {
if (StringUtils.isBlank(path)) {
return -;
}
File file = new File(path);
return (file.exists() && file.isFile() ? file.length() : -);
}
}

十三、assets和raw資源工具類 ResourceUtils.java

public class ResourceUtils {
private ResourceUtils() {
throw new AssertionError();
}
/**
* get an asset using ACCESS_STREAMING mode. This provides access to files that have been bundled with an
* application as assets -- that is, files placed in to the "assets" directory.
* 
* @param context
* @param fileName The name of the asset to open. This name can be hierarchical.
* @return
*/
public static String geFileFromAssets(Context context, String fileName) {
if (context == null || StringUtils.isEmpty(fileName)) {
return null;
}
StringBuilder s = new StringBuilder("");
try {
InputStreamReader in = new InputStreamReader(context.getResources().getAssets().open(fileName));
BufferedReader br = new BufferedReader(in);
String line;
while ((line = br.readLine()) != null) {
s.append(line);
}
return s.toString();
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
/**
* get content from a raw resource. This can only be used with resources whose value is the name of an asset files
* -- that is, it can be used to open drawable, sound, and raw resources; it will fail on string and color
* resources.
* 
* @param context
* @param resId The resource identifier to open, as generated by the appt tool.
* @return
*/
public static String geFileFromRaw(Context context, int resId) {
if (context == null) {
return null;
}
StringBuilder s = new StringBuilder();
try {
InputStreamReader in = new InputStreamReader(context.getResources().openRawResource(resId));
BufferedReader br = new BufferedReader(in);
String line;
while ((line = br.readLine()) != null) {
s.append(line);
}
return s.toString();
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
/**
* same to {@link ResourceUtils#geFileFromAssets(Context, String)}, but return type is List<String>
* 
* @param context
* @param fileName
* @return
*/
public static List<String> geFileToListFromAssets(Context context, String fileName) {
if (context == null || StringUtils.isEmpty(fileName)) {
return null;
}
List<String> fileContent = new ArrayList<String>();
try {
InputStreamReader in = new InputStreamReader(context.getResources().getAssets().open(fileName));
BufferedReader br = new BufferedReader(in);
String line;
while ((line = br.readLine()) != null) {
fileContent.add(line);
}
br.close();
return fileContent;
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
/**
* same to {@link ResourceUtils#geFileFromRaw(Context, int)}, but return type is List<String>
* 
* @param context
* @param resId
* @return
*/
public static List<String> geFileToListFromRaw(Context context, int resId) {
if (context == null) {
return null;
}
List<String> fileContent = new ArrayList<String>();
BufferedReader reader = null;
try {
InputStreamReader in = new InputStreamReader(context.getResources().openRawResource(resId));
reader = new BufferedReader(in);
String line = null;
while ((line = reader.readLine()) != null) {
fileContent.add(line);
}
reader.close();
return fileContent;
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
}

十四、單例工具類 SingletonUtils.java

public abstract class SingletonUtils<T> {
private T instance;
protected abstract T newInstance();
public final T getInstance() {
if (instance == null) {
synchronized (SingletonUtils.class) {
if (instance == null) {
instance = newInstance();
}
}
}
return instance;
}
}

十五、數據庫工具類 SqliteUtils.java

public class SqliteUtils {
private static volatile SqliteUtils instance;
private DbHelper dbHelper;
private SQLiteDatabase db;
private SqliteUtils(Context context) {
dbHelper = new DbHelper(context);
db = dbHelper.getWritableDatabase();
}
public static SqliteUtils getInstance(Context context) {
if (instance == null) {
synchronized (SqliteUtils.class) {
if (instance == null) {
instance = new SqliteUtils(context);
}
}
}
return instance;
}
public SQLiteDatabase getDb() {
return db;
}
}