Android 开发常用代码片段

               

1、图片旋转

Bitmap bitmapOrg = BitmapFactory.decodeResource(this.getContext().getResources(), R.drawable.moon);Matrix matrix = new Matrix();matrix.postRotate(-90);//旋转的角度 Bitmap resizedBitmap = Bitmap.createBitmap(bitmapOrg, 0, 0,                    bitmapOrg.getWidth(), bitmapOrg.getHeight(), matrix, true);BitmapDrawable bmd = new BitmapDrawable(resizedBitmap);

2、获取手机号码

//创建电话管理TelephonyManager tm = (TelephonyManager)//与手机建立连接activity.getSystemService(Context.TELEPHONY_SERVICE);//获取手机号码String phoneId = tm.getLine1Number();//记得在manifest file中添加    android.permission.READ_PHONE_STATE" />//程序在模拟器上无法实现，必须连接手机

3.格式化string.xml 中的字符串

// in strings.xml..Thanks for visiting %s. You age is %d!          // and in the java code:String.format(getString(R.string.my_text), "oschina", 33);

4、android设置全屏的方法

A.在java代码中设置

/** 全屏设置，隐藏窗口所有装饰 */requestWindowFeature(Window.FEATURE_NO_TITLE);getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,                WindowManager.LayoutParams.FLAG_FULLSCREEN);

B、在AndroidManifest.xml中配置

5、设置Activity为Dialog的形式

在AndroidManifest.xml中配置Activity节点是配置theme如下：

android:theme="@android:style/Theme.Dialog"

6、检查当前网络是否连上

ConnectivityManager con=(ConnectivityManager)getSystemService(Activity.CONNECTIVITY_SERVICE);   boolean wifi=con.getNetworkInfo(ConnectivityManager.TYPE_WIFI).isConnectedOrConnecting();  boolean internet=con.getNetworkInfo(ConnectivityManager.TYPE_MOBILE).isConnectedOrConnecting(); 

在AndroidManifest.xml 增加权限：

7、检测某个Intent是否有效

public static boolean isIntentAvailable(Context context, String action) {    final PackageManager packageManager = context.getPackageManager();    final Intent intent = new Intent(action);    List list =            packageManager.queryIntentActivities(intent,                    PackageManager.MATCH_DEFAULT_ONLY);    return list.size() > 0;}

8、android 拨打电话

try {   Intent intent = new Intent(Intent.ACTION_CALL);   intent.setData(Uri.parse("tel:+110"));   startActivity(intent);} catch (Exception e) {   Log.e("SampleApp", "Failed to invoke call", e);}

9、android中发送Email

Intent i = new Intent(Intent.ACTION_SEND);  //i.setType("text/plain"); //模拟器请使用这行i.setType("message/rfc822") ; // 真机上使用这行i.putExtra(Intent.EXTRA_EMAIL, new String[]{"[email protected]","[email protected]});  i.putExtra(Intent.EXTRA_SUBJECT,"subject goes here");  i.putExtra(Intent.EXTRA_TEXT,"body goes here");  startActivity(Intent.createChooser(i, "Select email application."));

10、android中打开浏览器

Intent viewIntent = new     Intent("android.intent.action.VIEW",Uri.parse("http://vaiyanzi.cnblogs.com"));startActivity(viewIntent);

11、android 获取设备唯一标识码

String android_id = Secure.getString(getContext().getContentResolver(), Secure.ANDROID_ID);

12、android中获取IP地址

public String getLocalIpAddress() {    try {        for (Enumeration en = NetworkInterface.getNetworkInterfaces();   en.hasMoreElements();) {            NetworkInterface intf = en.nextElement();            for (Enumeration enumIpAddr = intf.getInetAddresses();   enumIpAddr.hasMoreElements();) {                InetAddress inetAddress = enumIpAddr.nextElement();                if (!inetAddress.isLoopbackAddress()) {                    return inetAddress.getHostAddress().toString();                }            }        }    } catch (SocketException ex) {        Log.e(LOG_TAG, ex.toString());    }    return null;}

13、android获取存储卡路径以及使用情况

/** 获取存储卡路径 */ File sdcardDir=Environment.getExternalStorageDirectory(); /** StatFs 看文件系统空间使用情况 */ StatFs statFs=new StatFs(sdcardDir.getPath()); /** Block 的 size*/ Long blockSize=statFs.getBlockSize(); /** 总 Block 数量 */ Long totalBlocks=statFs.getBlockCount(); /** 已使用的 Block 数量 */ Long availableBlocks=statFs.getAvailableBlocks(); 

14 android中添加新的联系人

private Uri insertContact(Context context, String name, String phone) {           ContentValues values = new ContentValues();       values.put(People.NAME, name);       Uri uri = getContentResolver().insert(People.CONTENT_URI, values);       Uri numberUri = Uri.withAppendedPath(uri, People.Phones.CONTENT_DIRECTORY);       values.clear();              values.put(Contacts.Phones.TYPE, People.Phones.TYPE_MOBILE);       values.put(People.NUMBER, phone);       getContentResolver().insert(numberUri, values);              return uri;}

15、查看电池使用情况

Intent intentBatteryUsage = new Intent(Intent.ACTION_POWER_USAGE_SUMMARY);        startActivity(intentBatteryUsage);

16、获取进程号

ActivityManager mActivityManager = (ActivityManager) this.getSystemService(ACTIVITY_SERVICE);

List mRunningProcess = mActivityManager.getRunningAppProcesses();int i = 1; for (ActivityManager.RunningAppProcessInfo amProcess : mRunningProcess) {  Log.e("homer Application", (i++) + "  PID = " + amProcess.pid + "; processName = " + amProcess.processName);}   

参考推荐：

Android 获取屏幕尺寸与密度

Android 根据屏幕大小设置字体

Android Activity 全屏、横竖屏设置

Android模拟器无法上网问题

15、查看电池使用情况

Intent intentBatteryUsage = new Intent(Intent.ACTION_POWER_USAGE_SUMMARY);        startActivity(intentBatteryUsage);

           

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