Android开发——DeviceUtil，获取Android设备信息的工具类

• Android 设备工具DeviceUtil
• Android 设备工具DeviceUtil dp转换px px转换dp 设备宽度 设备高度 SD卡判断 网络判断 VersionName VersionCode DeviceId 手机品牌 手机型号 系统Android API等级 系统Android 版本 App进程id App进程Name 创建App缓存文件夹 Uri转换File 获取AndroidManifestxml里meta data的值 DeviceUtil全部源码
• dp转换px
• 在自定义View中必须用到这个方法。自定义View的时候，不能像在xml那样可以设置dp（密度），只能设置px（像素）。不同分辨率的设备，设置px，显示就不会一样了。为了结合设计图设置dp，需要将dp转换为px值，然后再设置。

import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.ActivityManager;
import android.app.Application;
import android.content.Context;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.Uri;
import android.os.Environment;
import android.provider.MediaStore;
import android.telephony.TelephonyManager;
import android.util.Log;
import java.io.File;
import java.util.Iterator;
import java.util.List;
public class DeviceUtil {
	 /**
	     * dp 转化为 px
	     * @param context
	     * @param pxValue
	     * @return
	     */
	  public static int dp2px(Context context, float dpValue) {
	        final float scale = context.getResources().getDisplayMetrics().density;
	        return (int) (dpValue * scale + 0.5f);
	    }
	px转换dp
	    /**
	     * px 转化为 dp
	     * @param context
	     * @param pxValue
	     * @return
	     */
	    public static int px2dp(Context context, float pxValue) {
	        final float scale = context.getResources().getDisplayMetrics().density;
	        return (int) (pxValue / scale + 0.5f);
	    }
	设备宽度
	    /**
	     * 获取设备宽度（px）
	     * @param context
	     * @return
	     */
	    public static int deviceWidth(Context context) {
	        return context.getResources().getDisplayMetrics().widthPixels;
	    }
	设备高度
	    /**
	     * 获取设备高度（px）
	     * @param context
	     * @return
	     */
	    public static int deviceHeight(Context context) {
	        return context.getResources().getDisplayMetrics().heightPixels;
	    }
	SD卡判断
	    /**
	     * SD卡判断
	     * @return
	     */
	    public static boolean isSDCardAvailable() {
	        return Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED);
	    }	


        /**
         * SD卡判断
         *
         * @return
         */
        public static boolean isSDCardAvailable() {
            return Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED);
        }

        /**
         * 是否有网
         *
         * @param context
         * @return
         */
        public static boolean isNetworkConnected(Context context) {
            if (context != null) {
                ConnectivityManager mConnectivityManager = (ConnectivityManager) context
                        .getSystemService(Context.CONNECTIVITY_SERVICE);
                NetworkInfo mNetworkInfo = mConnectivityManager
                        .getActiveNetworkInfo();
                if (mNetworkInfo != null) {
                    return mNetworkInfo.isAvailable();
                }
            }
            return false;
        }

        /**
         * 返回版本名字
         * 对应build.gradle中的versionName
         *
         * @param context
         * @return
         */
        public static String getVersionName(Context context) {
            String versionName ="" ;
            try {
                PackageManager packageManager = context.getPackageManager();
                PackageInfo packInfo = packageManager.getPackageInfo(context.getPackageName(), 0);
                versionName = packInfo.versionName;
            } catch (Exception e) {
                e.printStackTrace();
            }
            return versionName;
        }

        /**
         * 返回版本号
         * 对应build.gradle中的versionCode
         *
         * @param context
         * @return
         */
        public static String getVersionCode(Context context) {
            String versionCode = "";
            try {
                PackageManager packageManager = context.getPackageManager();
                PackageInfo packInfo = packageManager.getPackageInfo(context.getPackageName(), 0);
                versionCode = String.valueOf(packInfo.versionCode);
            } catch (Exception e) {
                e.printStackTrace();
            }
            return versionCode;
        }

        /**
         * 获取设备的唯一标识，deviceId
         *
         * @param context
         * @return
         */
        public static String getDeviceId(Context context) {
            TelephonyManager tm = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE);
            @SuppressLint("MissingPermission") String deviceId = tm.getDeviceId();
            if (deviceId == null) {
                return "";
            } else {
                return deviceId;
            }
        }

        /**
         * 获取手机品牌
         *
         * @return
         */
        public static String getPhoneBrand() {
            return android.os.Build.BRAND;
        }

        /**
         * 获取手机型号
         *
         * @return
         */
        public static String getPhoneModel() {
            return android.os.Build.MODEL;
        }

        /**
         * 获取手机Android API等级（22、23 ...）
         *
         * @return
         */
        public static int getBuildLevel() {
            return android.os.Build.VERSION.SDK_INT;
        }

        /**
         * 获取手机Android 版本（4.4、5.0、5.1 ...）
         *
         * @return
         */
        public static String getBuildVersion() {
            return android.os.Build.VERSION.RELEASE;
        }

        /**
         * 获取当前App进程的id
         *
         * @return
         */
        public static int getAppProcessId() {
            return android.os.Process.myPid();
        }

        /**
         * 获取当前App进程的Name
         *
         * @param context
         * @param processId
         * @return
         */
        public static String getAppProcessName(Context context, int processId) {
            String processName = null;
            ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
            // 获取所有运行App的进程集合
            List l = am.getRunningAppProcesses();
            Iterator i = l.iterator();
            PackageManager pm = context.getPackageManager();
            while (i.hasNext()) {
                ActivityManager.RunningAppProcessInfo info = (ActivityManager.RunningAppProcessInfo) (i.next());
                try {
                    if (info.pid == processId) {
                        CharSequence c = pm.getApplicationLabel(pm.getApplicationInfo(info.processName, PackageManager.GET_META_DATA));

                        processName = info.processName;
                        return processName;
                    }
                } catch (Exception e) {
                    Log.e(DeviceUtil.class.getName(), e.getMessage(), e);
                }
            }
            return processName;
        }

        /**
         * 创建App文件夹
         *
         * @param appName
         * @param application
         * @return
         */
        public static String createAPPFolder(String appName, Application application) {
            return createAPPFolder(appName, application, null);
        }

        /**
         * 创建App文件夹
         *
         * @param appName
         * @param application
         * @param folderName
         * @return
         */
        public static String createAPPFolder(String appName, Application application, String folderName) {
            File root = Environment.getExternalStorageDirectory();
            File folder;
            /**
             * 如果存在SD卡
             */
            if (DeviceUtil.isSDCardAvailable() && root != null) {
                folder = new File(root, appName);
                if (!folder.exists()) {
                    folder.mkdirs();
                }
            } else {
                /**
                 * 不存在SD卡，就放到缓存文件夹内
                 */
                root = application.getCacheDir();
                folder = new File(root, appName);
                if (!folder.exists()) {
                    folder.mkdirs();
                }
            }
            if (folderName != null) {
                folder = new File(folder, folderName);
                if (!folder.exists()) {
                    folder.mkdirs();
                }
            }
            return folder.getAbsolutePath();
        }

        /**
         * 通过Uri找到File
         *
         * @param context
         * @param uri
         * @return
         */
        public static File uri2File(Activity context, Uri uri) {
            File file;
            String[] project = {MediaStore.Images.Media.DATA};
            Cursor actualImageCursor = context.getContentResolver().query(uri, project, null, null, null);
            if (actualImageCursor != null) {
                int actual_image_column_index = actualImageCursor
                        .getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
                actualImageCursor.moveToFirst();
                String img_path = actualImageCursor
                        .getString(actual_image_column_index);
                file = new File(img_path);
            } else {
                file = new File(uri.getPath());
            }
            if (actualImageCursor != null) actualImageCursor.close();
            return file;
        }

        /**
         * 获取AndroidManifest.xml里 的值
         *
         * @param context
         * @param name
         * @return
         */
        public static String getMetaData(Context context, String name) {
            String value = null;
            try {
                ApplicationInfo appInfo = context.getPackageManager().getApplicationInfo(context.getPackageName(), PackageManager.GET_META_DATA);
                value = appInfo.metaData.getString(name);
            } catch (PackageManager.NameNotFoundException e) {
                e.printStackTrace();
            }
            return value;
        }


}