【Android】項目常用功能集錦（一）

今後會多收集項目中常用的小功能，提高以後的開發效率，好記星不如爛筆頭，好好寫部落格，好好學習。 1.驗證EditText

/**     * <判斷EditText是否為空白>     * @param edText     * @return     * @see [類、類#方法、類#成員]     */    public static boolean isEmptyEditText(EditText edText)    {        if (edText.getText().toString().trim().length() > 0)            return false;        else            return true;    }/**     * <驗證郵箱是否合法>     * @param email     * @return     * @see [類、類#方法、類#成員]     */    public static boolean isEmailIdValid(String email)    {        String expression = "^[\\w\\.-]+@([\\w\\-]+\\.)+[A-Z]{2,4}$";        CharSequence inputStr = email;        Pattern pattern = Pattern.compile(expression, Pattern.CASE_INSENSITIVE);        Matcher matcher = pattern.matcher(inputStr);        if (matcher.matches())            return true;        else            return false;    }

2.檢查網路連接狀態

/**     * 檢查網路連接狀態     *     * @param context     * @return true or false     */    public static boolean isNetworkAvailable(Context context)    {        ConnectivityManager cm = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);        NetworkInfo netInfo = cm.getActiveNetworkInfo();        if (netInfo != null && netInfo.isConnectedOrConnecting())        {            return true;        }        return false;    }

3.擷取應用表徵圖

/**     * <擷取當前應用的表徵圖>     * @param mContext     * @return     * @see [類、類#方法、類#成員]     */    public static Drawable getAppIcon(Context mContext)    {        Drawable icon = null;        final PackageManager pm = mContext.getPackageManager();        String packageName = mContext.getPackageName();        try        {            icon = pm.getApplicationIcon(packageName);            return icon;        }        catch (NameNotFoundException e1)        {            e1.printStackTrace();        }        return null;    }

4.發送本地通知

/**     * 發送本地通知     *     * @param mContext 上下文     * @param 通知的標題     * @param 通知的內容     * @param 點擊通知要開啟的Intent     */    @SuppressLint("NewApi")    @SuppressWarnings({"static-access"})    public static void sendLocatNotification(Context mContext, String title, String message, Intent mIntent)    {        int appIconResId = 0;        PendingIntent pIntent = null;        if (mIntent != null)            pIntent = PendingIntent.getActivity(mContext, 0, mIntent, PendingIntent.FLAG_UPDATE_CURRENT);        final PackageManager pm = mContext.getPackageManager();        String packageName = mContext.getPackageName();        ApplicationInfo applicationInfo;        try        {            applicationInfo = pm.getApplicationInfo(packageName, PackageManager.GET_META_DATA);            appIconResId = applicationInfo.icon;        }        catch (NameNotFoundException e1)        {            e1.printStackTrace();        }        // Notification notification = new Notification.Builder(mContext)        // .setSmallIcon(appIconResId).setWhen(System.currentTimeMillis())        // .setContentTitle(title).setContentText(message)        // .setContentIntent(pIntent).getNotification();        Notification notification;        if (mIntent == null)        {            notification =                new Notification.Builder(mContext).setSmallIcon(appIconResId)                    .setWhen(System.currentTimeMillis())                    .setContentTitle(message)                    .setStyle(new Notification.BigTextStyle().bigText(message))                    .setAutoCancel(true)                    .setContentText(message)                    .setContentIntent(PendingIntent.getActivity(mContext, 0, new Intent(), 0))                    .getNotification();        }        else        {            notification =                new Notification.Builder(mContext).setSmallIcon(appIconResId)                    .setWhen(System.currentTimeMillis())                    .setContentTitle(message)                    .setContentText(message)                    .setAutoCancel(true)                    .setStyle(new Notification.BigTextStyle().bigText(message))                    .setContentIntent(pIntent)                    .getNotification();        }        // 點擊之後清除通知        notification.flags |= Notification.FLAG_AUTO_CANCEL;        // 開啟通知提示音        notification.defaults |= Notification.DEFAULT_SOUND;        // 開啟震動        notification.defaults |= Notification.DEFAULT_VIBRATE;        NotificationManager manager = (NotificationManager)mContext.getSystemService(mContext.NOTIFICATION_SERVICE);        // manager.notify(0, notification);        manager.notify(R.string.app_name, notification);    }

5.隨機擷取

    /**     * <隨機擷取字母a-z>     * @return random num     * @see [類、類#方法、類#成員]     */    public static char getRandomCharacter()    {        Random r = new Random();        char c = (char)(r.nextInt(26) + 'a');        return c;    }    /**     * <擷取0到number之間的隨機數>     * @param number     * @return     * @see [類、類#方法、類#成員]     */    public static int getRandom(int number)    {        Random rand = new Random();        return rand.nextInt(number);    }

6.開啟日期和時間選取器

private static Calendar dateTime = Calendar.getInstance(); /**     * 開啟日期選取器     *     * @param mContext     * @param format     * @param mTextView 要顯示的TextView     */    public static void showDatePickerDialog(final Context mContext, final String format, final TextView mTextView)    {        new DatePickerDialog(mContext, new OnDateSetListener()        {            @Override            public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth)            {                SimpleDateFormat dateFormatter = new SimpleDateFormat(format);                dateTime.set(year, monthOfYear, dayOfMonth);                mTextView.setText(dateFormatter.format(dateTime.getTime()).toString());            }        }, dateTime.get(Calendar.YEAR), dateTime.get(Calendar.MONTH), dateTime.get(Calendar.DAY_OF_MONTH)).show();    }    /**     * 時間選取器     *     * @param mContext     * @param mTextView 要顯示的TextView     * @return show timepicker     */    public static void showTimePickerDialog(final Context mContext, final TextView mTextView)    {        new TimePickerDialog(mContext, new OnTimeSetListener()        {            @Override            public void onTimeSet(TimePicker view, int hourOfDay, int minute)            {                SimpleDateFormat timeFormatter = new SimpleDateFormat("hh:mm a");                dateTime.set(Calendar.HOUR_OF_DAY, hourOfDay);                dateTime.set(Calendar.MINUTE, minute);                mTextView.setText(timeFormatter.format(dateTime.getTime()).toString());            }        }, dateTime.get(Calendar.HOUR_OF_DAY), dateTime.get(Calendar.MINUTE), false).show();    }

7.擷取裝置寬高

/**     * 擷取裝置高度     *     * @param mContext     * @return 裝置高度     */    public static int getDeviceHeight(Context mContext)    {        DisplayMetrics displaymetrics = new DisplayMetrics();        ((Activity)mContext).getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);        return displaymetrics.heightPixels;    }    /**     * 擷取裝置寬度     *     * @param mContext     * @return 裝置寬度     */    public static int getDeviceWidth(Context mContext)    {        DisplayMetrics displaymetrics = new DisplayMetrics();        ((Activity)mContext).getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);        return displaymetrics.widthPixels;    }

8.String和List互轉

/**     * <String轉化為List>     * @param string     * @return     * @see [類、類#方法、類#成員]     */    public static List<String> stringToArrayList(String string)    {        List<String> strValueList = new ArrayList<String>();        strValueList = Arrays.asList(string.split(","));        return strValueList;    }    /**     * <List轉化為String>     * @param string     * @return     * @see [類、類#方法、類#成員]     */    public static String arrayListToString(List<String> list)    {        String strValue = null;        StringBuilder sb = new StringBuilder();        for (String s : list)        {            sb.append(s + ",");            strValue = sb.toString();        }        if (strValue.length() > 0 && strValue.charAt(strValue.length() - 1) == ',')        {            strValue = strValue.substring(0, strValue.length() - 1);        }        return strValue;    }

9.Bitmap和Drawable互轉

/**     *      * <drawable轉bitmap>     * @param mContext     * @param drawable     * @return     * @see [類、類#方法、類#成員]     */    public static Bitmap drawableTobitmap(Context mContext, int drawable)    {        Drawable myDrawable = mContext.getResources().getDrawable(drawable);        return ((BitmapDrawable)myDrawable).getBitmap();    }    /**     *      * <bitmap轉drawable>     * @param mContext     * @param drawable     * @return     * @see [類、類#方法、類#成員]     */    public static Drawable bitmapToDrawable(Context mContext, Bitmap bitmap)    {        return new BitmapDrawable(bitmap);    }

10.擷取應用版本號碼

/**     * <擷取應用版本號碼>     * @param mContext     * @return     * @see [類、類#方法、類#成員]     */    public static int getAppVersionCode(Context mContext)    {        PackageInfo pInfo = null;        try        {            pInfo = mContext.getPackageManager().getPackageInfo(mContext.getPackageName(), 0);        }        catch (NameNotFoundException e)        {            e.printStackTrace();        }        return pInfo.versionCode;    }