Android开发中4个常用的工具类【Toast、SharedPreferences、网络及屏幕操作】

本文实例讲述了Android开发中4个常用的工具类。分享给大家供大家参考，具体如下：

1、土司工具类（Toast管理）

/** * Toast统一管理类 * * @Project App_ZXing * @Package com.android.scan * @author chenlin * @version 1.0 * @Date 2013年7月6日 * @Note TODO */ public class ToastUtil { private ToastUtil() { /* cannot be instantiated */ throw new UnsupportedOperationException("cannot be instantiated"); } public static boolean isShow = true; /** * 短时间显示Toast * * @param context * @param message */ public static void show(Context context, CharSequence message) { if (isShow) Toast.makeText(context, message, Toast.LENGTH_SHORT).show(); } /** * 短时间显示Toast * * @param context * @param message */ public static void showShort(Context context, int message) { if (isShow) Toast.makeText(context, message, Toast.LENGTH_SHORT).show(); } /** * 长时间显示Toast * * @param context * @param message */ public static void showLong(Context context, CharSequence message) { if (isShow) Toast.makeText(context, message, Toast.LENGTH_LONG).show(); } /** * 长时间显示Toast * * @param context * @param message */ 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 * * @param context * @param message * @param duration */ 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 * * @param context * @param message * @param duration */ public static void show(Context context, int message, int duration) { if (isShow) Toast.makeText(context, message, duration).show(); } }

2、SharedPreferences工具类

/** * SharedPreferences封装类SPUtils * @Project App_ZXing * @Package com.android.scan * @author chenlin * @version 1.0 * @Date 2013年6月6日 * @Note TODO */ public class SPUtils { /** * 保存在手机里面的文件名 */ public static final String FILE_NAME = "share_data"; /** * 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 * * @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 * * @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; } /** * 移除某个key值已经对应的值 * * @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); } /** * 清除所有数据 * * @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); } /** * 查询某个key是否已经存在 * * @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); } /** * 返回所有的键值对 * * @param context * @return */ public static Map<String, ?> getAll(Context context) { SharedPreferences sp = context.getSharedPreferences(FILE_NAME, Context.MODE_PRIVATE); return sp.getAll(); } /** * 创建一个解决SharedPreferencesCompat.apply方法的一个兼容类 * * @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; } /** * 如果找到则使用apply执行，否则使用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(); } } }

3、网络工具类

/** * 跟网络相关的工具类 * @Project App_ZXing * @Package com.android.scan * @author chenlin * @version 1.0 * @Date 2013年6月8日 * @Note TODO */ public class NetUtils { private NetUtils() { /* cannot be instantiated */ throw new UnsupportedOperationException("cannot be instantiated"); } /** * 判断网络是否连接 * * @param context * @return */ 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; } /** * 判断是否是wifi连接 */ 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; } /** * 打开网络设置界面 */ 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, 0); } }

4、获得屏幕相关的辅助类

/** * 获得屏幕相关的辅助类 * @Project App_ZXing * @Package com.android.scan * @author chenlin * @version 1.0 * @Date 2013年6月6日 */ public class ScreenUtils { private ScreenUtils() { /* cannot be instantiated */ throw new UnsupportedOperationException("cannot be instantiated"); } /** * 获得屏幕高度 * * @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; } /** * 获得屏幕宽度 * * @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; } /** * 获得状态栏的高度 * * @param context * @return */ public static int getStatusHeight(Context context) { int statusHeight = -1; 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; } /** * 获取当前屏幕截图，包含状态栏 * * @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, 0, 0, width, height); view.destroyDrawingCache(); return bp; } /** * 获取当前屏幕截图，不包含状态栏 * * @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, 0, statusBarHeight, width, height - statusBarHeight); view.destroyDrawingCache(); return bp; } }

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希望本文所述对大家Android程序设计有所帮助。