Android实用代码，android实用,一、获取应用程序下所有A

Android实用代码，android实用,一、获取应用程序下所有A

一、获取应用程序下所有Activity

publicstaticArrayListgetActivities(Contextctx){ ArrayListresult=newArrayList(); Intentintent=newIntent(Intent.ACTION_MAIN,null); intent.setPackage(ctx.getPackageName()); for(ResolveInfoinfo:ctx.getPackageManager().queryIntentActivities(intent,0)){ result.add(info.activityInfo.name); } returnresult; }

二、检测字符串中是否包含汉字publicstaticbooleancheckChinese(Stringsequence){ finalStringformat="[\u4E00-\u9FA5\uF900-\uFA2D]"; booleanresult=false; Patternpattern=Pattern.compile(format); Matchermatcher=pattern.matcher(sequence); result=matcher.find(); returnresult; }

三、检测字符串中只能包含：中文、数字、下划线(_)、横线(-)

public static boolean checkNickname(String sequence) { final String format = "[^\u4E00-\u9FA5\uF900-\uFA2D\w-_]"; Pattern pattern = Pattern.compile(format); Matcher matcher = pattern.matcher(sequence); return !matcher.find(); }

四、使用TransitionDrawable实现渐变效果privatevoidsetImageBitmap(ImageViewimageView,Bitmapbitmap){ //UseTransitionDrawabletofadein. finalTransitionDrawabletd=newTransitionDrawable(newDrawable[]{newColorDrawable(android.R.color.transparent),newBitmapDrawable(mContext.getResources(),bitmap)}); //noinspectiondeprecation imageView.setBackgroundDrawable(imageView.getDrawable()); imageView.setImageDrawable(td); td.startTransition(200); }

比使用AlphaAnimation效果要好，可避免出现闪烁问题。

五、扫描指定的文件

sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, uri)); 用途：从本软件新增、修改、删除图片、文件某一个文件（音频、视频）需要更新系统媒体库时使用，不必扫描整个SD卡。

六、Dip转px public static int dipToPX(final Context ctx, float dip) { return (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dip, ctx.getResources().getDisplayMetrics()); }用途：难免在Activity代码中设置位置、大小等，本方法就很有用了！

七、发送不重复的通知（Notification） public static void sendNotification(Context context, String title, String message, Bundle extras) { Intent mIntent = new Intent(context, FragmentTabsActivity.class); mIntent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); mIntent.putExtras(extras);

    int requestCode = (int) System.currentTimeMillis();    PendingIntent mContentIntent = PendingIntent.getActivity(context,            requestCode, mIntent, 0);    Notification mNotification = new NotificationCompat.Builder(context)            .setContentTitle(title).setSmallIcon(R.drawable.app_icon)            .setContentIntent(mContentIntent).setContentText(message)            .build();    mNotification.flags |= Notification.FLAG_AUTO_CANCEL;    mNotification.defaults = Notification.DEFAULT_ALL;    NotificationManager mNotificationManager = (NotificationManager) context            .getSystemService(Context.NOTIFICATION_SERVICE);    mNotificationManager.notify(requestCode, mNotification);}代码说明：关键点在这个requestCode，这里使用的是当前系统时间，巧妙的保证了每次都是一个新的Notification产生。

八、代码设置TextView的样式

使用过自定义Dialog可能马上会想到用如下代码：

new TextView(this,null,R.style.text_style);

但你运行这代码你会发现毫无作用！正确用法：

new TextView(new ContextThemeWrapper(this, R.style.text_style))

九、 ip地址转成8位十六进制串

public static String ipToHex(String ips) {    StringBuffer result = new StringBuffer();    if (ips != null) {        StringTokenizer st = new StringTokenizer(ips, ".");        while (st.hasMoreTokens()) {            String token = Integer.toHexString(Integer.parseInt(st.nextToken()));            if (token.length() == 1)                token = "0" + token;            result.append(token);        }    }    return result.toString();}public static String texToIp(String ips) {    try {        StringBuffer result = new StringBuffer();        if (ips != null &amp;&amp; ips.length() == 8) {            for (int i = 0; i < 8; i += 2) {                if (i != 0)                    result.append('.');                result.append(Integer.parseInt(ips.substring(i, i + 2), 16));            }        }        return result.toString();    } catch (NumberFormatException ex) {        Logger.e(ex);    }    return "";}

ip:192.168.68.128 16 =>hex :c0a84480

十、WebView保留缩放功能但隐藏缩放控件 mWebView.getSettings().setSupportZoom(true); mWebView.getSettings().setBuiltInZoomControls(true); if (DeviceUtils.hasHoneycomb()) mWebView.getSettings().setDisplayZoomControls(false); 注意：setDisplayZoomControls是在API Level 11中新增。

十一、获取网络类型名称 public static String getNetworkTypeName(Context context) { if (context != null) { ConnectivityManager connectMgr = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE); if (connectMgr != null) { NetworkInfo info = connectMgr.getActiveNetworkInfo(); if (info != null) { switch (info.getType()) { case ConnectivityManager.TYPE_WIFI: return "WIFI"; case ConnectivityManager.TYPE_MOBILE: return getNetworkTypeName(info.getSubtype()); } } } } return getNetworkTypeName(TelephonyManager.NETWORK_TYPE_UNKNOWN); }

public static String getNetworkTypeName(int type) {    switch (type) {    case TelephonyManager.NETWORK_TYPE_GPRS:        return "GPRS";    case TelephonyManager.NETWORK_TYPE_EDGE:        return "EDGE";    case TelephonyManager.NETWORK_TYPE_UMTS:        return "UMTS";    case TelephonyManager.NETWORK_TYPE_HSDPA:        return "HSDPA";    case TelephonyManager.NETWORK_TYPE_HSUPA:        return "HSUPA";    case TelephonyManager.NETWORK_TYPE_HSPA:        return "HSPA";    case TelephonyManager.NETWORK_TYPE_CDMA:        return "CDMA";    case TelephonyManager.NETWORK_TYPE_EVDO_0:        return "CDMA - EvDo rev. 0";    case TelephonyManager.NETWORK_TYPE_EVDO_A:        return "CDMA - EvDo rev. A";    case TelephonyManager.NETWORK_TYPE_EVDO_B:        return "CDMA - EvDo rev. B";    case TelephonyManager.NETWORK_TYPE_1xRTT:        return "CDMA - 1xRTT";    case TelephonyManager.NETWORK_TYPE_LTE:        return "LTE";    case TelephonyManager.NETWORK_TYPE_EHRPD:        return "CDMA - eHRPD";    case TelephonyManager.NETWORK_TYPE_IDEN:        return "iDEN";    case TelephonyManager.NETWORK_TYPE_HSPAP:        return "HSPA+";    default:        return "UNKNOWN";    }}

十二、Android解压Zip包

public static void UnZipFolder(String zipFileString, String outPathString) throws Exception {    java.util.zip.ZipInputStream inZip = new java.util.zip.ZipInputStream(new java.io.FileInputStream(zipFileString));    java.util.zip.ZipEntry zipEntry;    String szName = "";    while ((zipEntry = inZip.getNextEntry()) != null) {        szName = zipEntry.getName();        if (zipEntry.isDirectory()) {            // get the folder name of the widget            szName = szName.substring(0, szName.length() - 1);            java.io.File folder = new java.io.File(outPathString + java.io.File.separator + szName);            folder.mkdirs();        } else {            java.io.File file = new java.io.File(outPathString + java.io.File.separator + szName);            file.createNewFile();            // get the output stream of the file            java.io.FileOutputStream out = new java.io.FileOutputStream(file);            int len;            byte[] buffer = new byte[1024];            // read (len) bytes into buffer            while ((len = inZip.read(buffer)) != -1) {                // write (len) byte from buffer at the position                 out.write(buffer, 0, len);                out.flush();            }            out.close();        }    }//end of while    inZip.close();}//end of func

十三、 从assets中读取文本和图片资源

public static String getTextFromAssets(final Context context, String fileName) {    String result = "";    try {        InputStream in = context.getResources().getAssets().open(fileName);        // 获取文件的字节数        int lenght = in.available();        // 创建byte数组        byte[] buffer = new byte[lenght];        // 将文件中的数据读到byte数组中        in.read(buffer);        result = EncodingUtils.getString(buffer, "UTF-8");        in.close();    } catch (Exception e) {        e.printStackTrace();    }    return result;}public static Drawable loadImageFromAsserts(final Context ctx, String fileName) {    try {        InputStream is = ctx.getResources().getAssets().open(fileName);        return Drawable.createFromStream(is, null);    } catch (IOException e) {        if (e != null) {            e.printStackTrace();        }    } catch (OutOfMemoryError e) {        if (e != null) {            e.printStackTrace();        }    } catch (Exception e) {        if (e != null) {            e.printStackTrace();        }    }    return null;}