【Android】項目常用功能集錦（一）

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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，好好寫博客，好好學習。

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1.驗證EditText

/**
     * <判斷EditText是否爲空>
     * @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.檢查網絡連接狀態

/**
     * 檢查網絡連接狀態
     *
     * @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.獲取應用圖標

/**
     * <獲取當前應用的圖標>
     * @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 點擊通知要打開的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;
        // 開啓通知提示音
        notification.defaults |= Notification.DEFAULT_SOUND;
        // 開啓震動
        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.隨機獲取

    /**
     * <隨機獲取字母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;
    }

    /**
     * <獲取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.打開日期和時間選擇器

private static Calendar dateTime = Calendar.getInstance();


 /**
     * 打開日期選擇器
     *
     * @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();
    }

    /**
     * 時間選擇器
     *
     * @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.獲取設備寬高

/**
     * 獲取設備高度
     *
     * @param mContext
     * @return 設備高度
     */
    public static int getDeviceHeight(Context mContext)
    {
        DisplayMetrics displaymetrics = new DisplayMetrics();
        ((Activity)mContext).getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
        return displaymetrics.heightPixels;
    }

    /**
     * 獲取設備寬度
     *
     * @param mContext
     * @return 設備寬度
     */
    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轉化爲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轉化爲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.獲取應用版本號

/**
     * <獲取應用版本號>
     * @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;
    }