Android 开发实用方法大全
1.格式化价格，这个经常在计算费用精度的时候用到
/** * 格式化价格 * * @param argStr 传入价格字符串 * @return */ public static String getFloatDotStr(String argStr) { float arg = Float.valueOf(argStr); DecimalFormat fnum = new DecimalFormat("##0.00"); return fnum.format(arg); }
2.获取App的版本号Version
// 得到versionCode public static int getVerCode(Context context) { int verCode = 0; try { verCode = context.getPackageManager().getPackageInfo(context.getPackageName(), 0).versionCode; } catch (NameNotFoundException e) { e.printStackTrace(); } return verCode; }
3.获取手机屏幕宽高：
/** * 屏幕宽高 * * @param context * @return 0:width，1:height */ public static int[] ScreenSize(Context context) { DisplayMetrics metrics = new DisplayMetrics(); ((WindowManager) context.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay().getMetrics(metrics); return new int[] { metrics.widthPixels, metrics.heightPixels }; }
4.判断SD卡是否存在：
/** * 判断sd卡是否存在 * * @author * @return */ public static boolean judgeSDCard() { String status = Environment.getExternalStorageState(); return status.equals(Environment.MEDIA_MOUNTED); }
5.验证是否中文：
/*** * 验证是否中文 * * @param * @return */ public static boolean validName(String name) { String pattern = "[\u4e00-\u9fa5]"; if (isNull(name)) return false; return name.matches(pattern); }
6.验证身份证号码：
/** * 验证身份证号码 * * @author * @param idCard * @return */ public static boolean validateIdCard(String idCard) { if (isNull(idCard)) return false; String pattern = "^[0-9]{17}[0-9|xX]{1}$"; return idCard.matches(pattern); }
7.验证手机号码：
/** * 验证手机号码 * * @author * @param phone * @return */ public static boolean validatePhone(String phone) { if (isNull(phone)) return false; String pattern = "^1[3,4,5,6,8]\\d{9}$"; return phone.matches(pattern); }
8.验证邮编：
/** * 判断邮编 * * @param * @return */ public static boolean isZipNO(String zipString) { String str = "^[1-9][0-9]{5}$"; return Pattern.compile(str).matcher(zipString).matches(); }
9.验证银行卡号：
/** * 验证银行卡号 * * @param bankCard * 信用卡是16位，其他的是13-19位 * @return */ public static boolean validateBankCard(String bankCard) { if (isNull(bankCard)) return false; String pattern = "^\\d{13,19}$"; return bankCard.matches(pattern); }
10.验证邮箱：
/** * 验证邮箱 * * @author * @param email * @return */ public static boolean validateEmail(String email) { if (isNull(email)) return false; String pattern = "^([a-zA-Z0-9_\\.\\-])+\\@(([a-zA-Z0-9\\-])+\\.)+([a-zA-Z0-9]{2,4})+$"; return email.matches(pattern); }
11.将图片设置为圆角图片：
/** * 设置圆角的图片 * * @author * @param bitmap * 图片 * @param pixels * 角度 * @return */ public static Bitmap toRoundCorner(Bitmap bitmap, int pixels) { try { if (bitmap != null) { Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Config.ARGB_8888); Canvas canvas = new Canvas(output); final int color = 0xff424242; final Paint paint = new Paint(); final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight()); final RectF rectF = new RectF(rect); final float roundPx = pixels; paint.setAntiAlias(true); canvas.drawARGB(0, 0, 0, 0); paint.setColor(color); canvas.drawRoundRect(rectF, roundPx, roundPx, paint); paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN)); canvas.drawBitmap(bitmap, rect, rect, paint); return output; } } catch (Exception e) { } return bitmap; } /** * 将图片转换为圆形的 * * @author * @param bitmap * @return */ public static Bitmap toRoundBitmap(Bitmap bitmap) { if (bitmap != null) { bitmap = cutSquareBitmap(bitmap); return toRoundCorner(bitmap, bitmap.getWidth() / 2); } return bitmap; }
12.判断有无网络链接
// 判断有无网络链接 public static boolean checkNetworkInfo(Context mContext) { ConnectivityManager conMan = (ConnectivityManager) mContext.getSystemService(Context.CONNECTIVITY_SERVICE); State mobile = conMan.getNetworkInfo(ConnectivityManager.TYPE_MOBILE).getState(); State wifi = conMan.getNetworkInfo(ConnectivityManager.TYPE_WIFI).getState(); if (mobile == State.CONNECTED || mobile == State.CONNECTING) return true; if (wifi == State.CONNECTED || wifi == State.CONNECTING) return true; return false; }
13.判断是否连接wifi
/** * 判断是否连接wifi * * @param mContext * @return 返回true则有wifi */ private static boolean isWifi(Context mContext) { ConnectivityManager connectivityManager = (ConnectivityManager) mContext.getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo activeNetInfo = connectivityManager.getActiveNetworkInfo(); if (activeNetInfo != null && activeNetInfo.getType() == ConnectivityManager.TYPE_WIFI) { return true; } return false; }
14.获取SIM卡存在的状态
/** 获取SIM卡存在的状态 */ public static String getSIMCardExist(Context context) { manager = (TelephonyManager) context.getSystemService(context.TELEPHONY_SERVICE); String state = ""; switch (manager.getSimState()) { case TelephonyManager.SIM_STATE_READY: state = "良好"; break; case TelephonyManager.SIM_STATE_ABSENT: state = "无SIM卡"; break; default: state = "SIM卡被锁定或未知状态"; break; } return state; }
15. bitmap和base64类型互转
// 把bitmap转换成base64 public static String getBase64FromBitmap(Bitmap bitmap, int bitmapQuality) { ByteArrayOutputStream bStream = new ByteArrayOutputStream(); bitmap.compress(CompressFormat.JPEG, bitmapQuality, bStream); byte[] bytes = bStream.toByteArray(); return Base64.encode(bytes); } // 把base64转换成bitmap public static Bitmap getBitmapFromBase64(String string) { byte[] bitmapArray = null; try { bitmapArray = Base64.decode(string); } catch (Exception e) { e.printStackTrace(); } return BitmapFactory.decodeByteArray(bitmapArray, 0, bitmapArray.length); }
16. 把图片流转换成byte数组
/** * * 方法说明 把图片流转换成byte数组 * * @author * @param * @return */ public static byte[] getByteFromStream(InputStream inStream) { byte[] data = new byte[1024]; byte[] buffer = new byte[1024]; int len = -1; ByteArrayOutputStream outStream = new ByteArrayOutputStream(); try { while ((len = inStream.read(buffer)) != -1) { outStream.write(buffer, 0, len); } data = outStream.toByteArray(); } catch (IOException e) { e.printStackTrace(); } finally { try { outStream.close(); inStream.close(); } catch (IOException e) { e.printStackTrace(); } } return data; }
17.把字节数组转化成bitmap
/** * * 把字节数组转化成bitmap * * @author * @param * @return */ public static Bitmap getBitmapFromBytes(byte[] bytes, BitmapFactory.Options opts) { if (bytes != null) if (opts != null) return BitmapFactory.decodeByteArray(bytes, 0, bytes.length, opts); else return BitmapFactory.decodeByteArray(bytes, 0, bytes.length); return null; }
18.把Stream转换成String
// 把Stream转换成String public static String convertStreamToString(InputStream is) { BufferedReader reader = new BufferedReader(new InputStreamReader(is)); StringBuilder sb = new StringBuilder(); String line = null; try { while ((line = reader.readLine()) != null) { sb.append(line + "/n"); } } catch (IOException e) { e.printStackTrace(); } finally { try { is.close(); } catch (IOException e) { e.printStackTrace(); } } return sb.toString(); }
19.防止按钮连续点击
/** * 防止按钮连续点击 */ private static long lastClickTime; public static boolean isFastDoubleClick() { long time = System.currentTimeMillis(); long timeD = time - lastClickTime; if (0 < timeD && timeD < 500) { return true; } lastClickTime = time; return false; }
20.保存图片到SD卡
/** * 保存图片 * * @param photoBitmap * @param path 保存路径 */ public static void savePhotoToSDCard(Bitmap photoBitmap, String path) { File photoFile = new File(path); FileOutputStream fileOutputStream = null; try { fileOutputStream = new FileOutputStream(photoFile); if (photoBitmap != null) { if (photoBitmap.compress(Bitmap.CompressFormat.JPEG, 70, fileOutputStream)) { fileOutputStream.flush(); } } } catch (FileNotFoundException e) { photoFile.delete(); e.printStackTrace(); } catch (IOException e) { photoFile.delete(); e.printStackTrace(); } finally { try { fileOutputStream.close(); } catch (IOException e) { e.printStackTrace(); } } }
21.将字符串转化为二维码：
private static int QR_WIDTH = 300; private static int QR_HEIGHT = 300; public static Bitmap createQRImage(String url) { try { // 判断URL合法性 if (url == null || "".equals(url) || url.length() < 1) { return null; } Hashtable<EncodeHintType, String> hints = new Hashtable<EncodeHintType, String>(); hints.put(EncodeHintType.CHARACTER_SET, "utf-8"); // 图像数据转换，使用了矩阵转换 BitMatrix bitMatrix = new QRCodeWriter().encode(url, BarcodeFormat.QR_CODE, QR_WIDTH, QR_HEIGHT); int[] pixels = new int[QR_WIDTH * QR_HEIGHT]; // 下面这里按照二维码的算法，逐个生成二维码的图片， // 两个for循环是图片横列扫描的结果 for (int y = 0; y < QR_HEIGHT; y++) { for (int x = 0; x < QR_WIDTH; x++) { if (bitMatrix.get(x, y)) { pixels[y * QR_WIDTH + x] = 0xff000000; } else { pixels[y * QR_WIDTH + x] = 0xffffffff; } } } // 生成二维码图片的格式，使用ARGB_8888 Bitmap bitmap = Bitmap.createBitmap(QR_WIDTH, QR_HEIGHT, Bitmap.Config.ARGB_8888); bitmap.setPixels(pixels, 0, QR_WIDTH, 0, 0, QR_WIDTH, QR_HEIGHT); return bitmap; } catch (Exception e) { e.printStackTrace(); } return null; }
22.得到自定义进度框：
/** * 得到自定义的progressDialog * * @param context * @param msg * @param bCancel * 按返回键是否取消 * @return */ public static Dialog createLoadingDialog(Context context, String msg, boolean bCancel) { LayoutInflater inflater = LayoutInflater.from(context); View v = inflater.inflate(R.layout.loading_dialog, null);// 得到加载view LinearLayout layout = (LinearLayout) v.findViewById(R.id.dialog_view);// 加载布局 // main.xml中的ImageView ImageView spaceshipImage = (ImageView) v.findViewById(R.id.img); TextView tipTextView = (TextView) v.findViewById(R.id.tipTextView);// 提示文字 // 加载动画 Animation hyperspaceJumpAnimation = AnimationUtils.loadAnimation(context, R.anim.loading_animation); // 使用ImageView显示动画 spaceshipImage.startAnimation(hyperspaceJumpAnimation); tipTextView.setText(msg);// 设置加载信息 Dialog loadingDialog = new Dialog(context, R.style.loading_dialog);// 创建自定义样式dialog loadingDialog.setCancelable(bCancel);// 不可以用“返回键”取消 loadingDialog.setCanceledOnTouchOutside(false); loadingDialog.setContentView(layout, new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT));// 设置布局 return loadingDialog; }
