android开发工具类总结
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一、日志工具类 Log.java
1 public class L 2 { 3 private L() 4 { 5 /* 不可被实例化 */ 6 throw new UnsupportedOperationException("Cannot be instantiated!"); 7 } 8 // 是否需要打印bug，可以在application的onCreate函数里面初始化 9 public static boolean isDebug = true; 10 private static final String TAG = "DefaultTag"; 11 12 // 下面四个是默认tag的函数 13 public static void i(String msg) 14 { 15 if (isDebug) 16 Log.i(TAG, msg); 17 } 18 19 public static void d(String msg) 20 { 21 if (isDebug) 22 Log.d(TAG, msg); 23 } 24 25 public static void e(String msg) 26 { 27 if (isDebug) 28 Log.e(TAG, msg); 29 } 30 31 public static void v(String msg) 32 { 33 if (isDebug) 34 Log.v(TAG, msg); 35 } 36 37 // 下面是传入自定义tag的函数 38 public static void i(String tag, String msg) 39 { 40 if (isDebug) 41 Log.i(tag, msg); 42 } 43 44 public static void d(String tag, String msg) 45 { 46 if (isDebug) 47 Log.i(tag, msg); 48 } 49 50 public static void e(String tag, String msg) 51 { 52 if (isDebug) 53 Log.i(tag, msg); 54 } 55 56 public static void v(String tag, String msg) 57 { 58 if (isDebug) 59 Log.i(tag, msg); 60 } 61 }
二、Toast统一管理类 Tost.java
public class T { private T() { /* cannot be instantiated */ throw new UnsupportedOperationException("cannot be instantiated"); } public static boolean isShow = true; /** * 短时间显示Toast */ public static void showShort(Context context, CharSequence message) { if (isShow) Toast.makeText(context, message, Toast.LENGTH_SHORT).show(); } /** * 短时间显示Toast * @param message 要显示的字符串资源的id */ public static void showShort(Context context, int message) { if (isShow) Toast.makeText(context, message, Toast.LENGTH_SHORT).show(); } /** * 长时间显示Toast */ public static void showLong(Context context, CharSequence message) { if (isShow) Toast.makeText(context, message, Toast.LENGTH_LONG).show(); } /** * 长时间显示Toast */ public static void showLong(Context context, int message) { if (isShow) Toast.makeText(context, message, Toast.LENGTH_LONG).show(); } /** * 自定义显示Toast时间 */ public static void show(Context context, CharSequence message, int duration) { if (isShow) Toast.makeText(context, message, duration).show(); } /** * 自定义显示Toast时间 */ public static void show(Context context, int message, int duration) { if (isShow) Toast.makeText(context, message, duration).show(); } }
三、SharedPreferences封装类 SPUtils.java 和 PreferencesUtils.java
1. SPUtils.java
1 public class SPUtils 2 { 3 /** 4 * 保存在手机里面的文件名 5 */ 6 public static final String FILE_NAME = "share_data"; 7 8 /** 9 * 保存数据的方法，我们需要拿到保存数据的具体类型，然后根据类型调用不同的保存方法 10 * 11 * @param context 12 * @param key 13 * @param object 14 */ 15 public static void put(Context context, String key, Object object) 16 { 17 18 SharedPreferences sp = context.getSharedPreferences(FILE_NAME, 19 Context.MODE_PRIVATE); 20 SharedPreferences.Editor editor = sp.edit(); 21 22 if (object instanceof String) 23 { 24 editor.putString(key, (String) object); 25 } else if (object instanceof Integer) 26 { 27 editor.putInt(key, (Integer) object); 28 } else if (object instanceof Boolean) 29 { 30 editor.putBoolean(key, (Boolean) object); 31 } else if (object instanceof Float) 32 { 33 editor.putFloat(key, (Float) object); 34 } else if (object instanceof Long) 35 { 36 editor.putLong(key, (Long) object); 37 } else 38 { 39 editor.putString(key, object.toString()); 40 } 41 42 SharedPreferencesCompat.apply(editor); 43 } 44 45 /** 46 * 得到保存数据的方法，我们根据默认值得到保存的数据的具体类型，然后调用相对于的方法获取值 47 * 48 * @param context 49 * @param key 50 * @param defaultObject 51 * @return 52 */ 53 public static Object get(Context context, String key, Object defaultObject) 54 { 55 SharedPreferences sp = context.getSharedPreferences(FILE_NAME, 56 Context.MODE_PRIVATE); 57 58 if (defaultObject instanceof String) 59 { 60 return sp.getString(key, (String) defaultObject); 61 } else if (defaultObject instanceof Integer) 62 { 63 return sp.getInt(key, (Integer) defaultObject); 64 } else if (defaultObject instanceof Boolean) 65 { 66 return sp.getBoolean(key, (Boolean) defaultObject); 67 } else if (defaultObject instanceof Float) 68 { 69 return sp.getFloat(key, (Float) defaultObject); 70 } else if (defaultObject instanceof Long) 71 { 72 return sp.getLong(key, (Long) defaultObject); 73 } 74 75 return null; 76 } 77 78 /** 79 * 移除某个key值已经对应的值 80 * @param context 81 * @param key 82 */ 83 public static void remove(Context context, String key) 84 { 85 SharedPreferences sp = context.getSharedPreferences(FILE_NAME, 86 Context.MODE_PRIVATE); 87 SharedPreferences.Editor editor = sp.edit(); 88 editor.remove(key); 89 SharedPreferencesCompat.apply(editor); 90 } 91 92 /** 93 * 清除所有数据 94 * @param context 95 */ 96 public static void clear(Context context) 97 { 98 SharedPreferences sp = context.getSharedPreferences(FILE_NAME, 99 Context.MODE_PRIVATE); 100 SharedPreferences.Editor editor = sp.edit(); 101 editor.clear(); 102 SharedPreferencesCompat.apply(editor); 103 } 104 105 /** 106 * 查询某个key是否已经存在 107 * @param context 108 * @param key 109 * @return 110 */ 111 public static boolean contains(Context context, String key) 112 { 113 SharedPreferences sp = context.getSharedPreferences(FILE_NAME, 114 Context.MODE_PRIVATE); 115 return sp.contains(key); 116 } 117 118 /** 119 * 返回所有的键值对 120 * 121 * @param context 122 * @return 123 */ 124 public static Map<String, ?> getAll(Context context) 125 { 126 SharedPreferences sp = context.getSharedPreferences(FILE_NAME, 127 Context.MODE_PRIVATE); 128 return sp.getAll(); 129 } 130 131 /** 132 * 创建一个解决SharedPreferencesCompat.apply方法的一个兼容类 133 * 134 * @author zhy 135 * 136 */ 137 private static class SharedPreferencesCompat 138 { 139 private static final Method sApplyMethod = findApplyMethod(); 140 141 /** 142 * 反射查找apply的方法 143 * 144 * @return 145 */ 146 @SuppressWarnings({ "unchecked", "rawtypes" }) 147 private static Method findApplyMethod() 148 { 149 try 150 { 151 Class clz = SharedPreferences.Editor.class; 152 return clz.getMethod("apply"); 153 } catch (NoSuchMethodException e) 154 { 155 } 156 157 return null; 158 } 159 160 /** 161 * 如果找到则使用apply执行，否则使用commit 162 * 163 * @param editor 164 */ 165 public static void apply(SharedPreferences.Editor editor) 166 { 167 try 168 { 169 if (sApplyMethod != null) 170 { 171 sApplyMethod.invoke(editor); 172 return; 173 } 174 } catch (IllegalArgumentException e) 175 { 176 } catch (IllegalAccessException e) 177 { 178 } catch (InvocationTargetException e) 179 { 180 } 181 editor.commit(); 182 } 183 } 184 185 }
对SharedPreference的使用做了建议的封装，对外公布出put，get，remove，clear等等方法；
- 注意一点，里面所有的commit操作使用了SharedPreferencesCompat.apply进行了替代，目的是尽可能的使用apply代替commit.
- 首先说下为什么，因为commit方法是同步的，并且我们很多时候的commit操作都是UI线程中，毕竟是IO操作，尽可能异步；
- 所以我们使用apply进行替代，apply异步的进行写入；
- 但是apply相当于commit来说是new API呢，为了更好的兼容，我们做了适配；
- SharedPreferencesCompat也可以给大家创建兼容类提供了一定的参考
2. SPUtils.java
1 public class PreferencesUtils { 2 3 public static String PREFERENCE_NAME = "TrineaandroidCommon"; 4 5 private PreferencesUtils() { 6 throw new AssertionError(); 7 } 8 9 /** 10 * put string preferences 11 * 12 * @param context 13 * @param key The name of the preference to modify 14 * @param value The new value for the preference 15 * @return True if the new values were successfully written to persistent storage. 16 */ 17 public static boolean putString(Context context, String key, String value) { 18 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE); 19 SharedPreferences.Editor editor = settings.edit(); 20 editor.putString(key, value); 21 return editor.commit(); 22 } 23 24 /** 25 * get string preferences 26 * 27 * @param context 28 * @param key The name of the preference to retrieve 29 * @return The preference value if it exists, or null. Throws ClassCastException if there is a preference with this 30 * name that is not a string 31 * @see #getString(Context, String, String) 32 */ 33 public static String getString(Context context, String key) { 34 return getString(context, key, null); 35 } 36 37 /** 38 * get string preferences 39 * 40 * @param context 41 * @param key The name of the preference to retrieve 42 * @param defaultValue Value to return if this preference does not exist 43 * @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with 44 * this name that is not a string 45 */ 46 public static String getString(Context context, String key, String defaultValue) { 47 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE); 48 return settings.getString(key, defaultValue); 49 } 50 51 /** 52 * put int preferences 53 * 54 * @param context 55 * @param key The name of the preference to modify 56 * @param value The new value for the preference 57 * @return True if the new values were successfully written to persistent storage. 58 */ 59 public static boolean putInt(Context context, String key, int value) { 60 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE); 61 SharedPreferences.Editor editor = settings.edit(); 62 editor.putInt(key, value); 63 return editor.commit(); 64 } 65 66 /** 67 * get int preferences 68 * 69 * @param context 70 * @param key The name of the preference to retrieve 71 * @return The preference value if it exists, or -1. Throws ClassCastException if there is a preference with this 72 * name that is not a int 73 * @see #getInt(Context, String, int) 74 */ 75 public static int getInt(Context context, String key) { 76 return getInt(context, key, -1); 77 } 78 79 /** 80 * get int preferences 81 * 82 * @param context 83 * @param key The name of the preference to retrieve 84 * @param defaultValue Value to return if this preference does not exist 85 * @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with 86 * this name that is not a int 87 */ 88 public static int getInt(Context context, String key, int defaultValue) { 89 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE); 90 return settings.getInt(key, defaultValue); 91 } 92 93 /** 94 * put long preferences 95 * 96 * @param context 97 * @param key The name of the preference to modify 98 * @param value The new value for the preference 99 * @return True if the new values were successfully written to persistent storage. 100 */ 101 public static boolean putLong(Context context, String key, long value) { 102 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE); 103 SharedPreferences.Editor editor = settings.edit(); 104 editor.putLong(key, value); 105 return editor.commit(); 106 } 107 108 /** 109 * get long preferences 110 * 111 * @param context 112 * @param key The name of the preference to retrieve 113 * @return The preference value if it exists, or -1. Throws ClassCastException if there is a preference with this 114 * name that is not a long 115 * @see #getLong(Context, String, long) 116 */ 117 public static long getLong(Context context, String key) { 118 return getLong(context, key, -1); 119 } 120 121 /** 122 * get long preferences 123 * 124 * @param context 125 * @param key The name of the preference to retrieve 126 * @param defaultValue Value to return if this preference does not exist 127 * @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with 128 * this name that is not a long 129 */ 130 public static long getLong(Context context, String key, long defaultValue) { 131 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE); 132 return settings.getLong(key, defaultValue); 133 } 134 135 /** 136 * put float preferences 137 * 138 * @param context 139 * @param key The name of the preference to modify 140 * @param value The new value for the preference 141 * @return True if the new values were successfully written to persistent storage. 142 */ 143 public static boolean putFloat(Context context, String key, float value) { 144 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE); 145 SharedPreferences.Editor editor = settings.edit(); 146 editor.putFloat(key, value); 147 return editor.commit(); 148 } 149 150 /** 151 * get float preferences 152 * 153 * @param context 154 * @param key The name of the preference to retrieve 155 * @return The preference value if it exists, or -1. Throws ClassCastException if there is a preference with this 156 * name that is not a float 157 * @see #getFloat(Context, String, float) 158 */ 159 public static float getFloat(Context context, String key) { 160 return getFloat(context, key, -1); 161 } 162 163 /** 164 * get float preferences 165 * 166 * @param context 167 * @param key The name of the preference to retrieve 168 * @param defaultValue Value to return if this preference does not exist 169 * @return The preference value if it exists, or defValue. Throws ClassCastException if there is a preference with 170 * this name that is not a float 171 */ 172 public static float getFloat(Context context, String key, float defaultValue) { 173 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE); 174 return settings.getFloat(key, defaultValue); 175 } 176 177 /** 178 * put boolean preferences 179 * 180 * @param context 181 * @param key The name of the preference to modify 182 * @param value The new value for the preference 183 * @return True if the new values were successfully written to persistent storage. 184 */ 185 public static boolean putBoolean(Context context, String key, boolean value) { 186 SharedPreferences settings = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE); 187 SharedPreferences.Editor editor = settings.edit(); 188 editor.putBoolean(key, value); 189 return editor.commit(); 190 } 191 192 /** 193 * get boolean preferences, default is false 194 * 195 * @param context 196 * @param key The name of the preference to retrieve 197 * @return The preference value if it exists, or false. 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