导航页
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<?xml version="1.0" encoding="utf-8"?> <android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context="com.example.hp.myapplication.MainActivity"> <android.support.v4.view.ViewPager android:layout_width="match_parent" android:layout_height="match_parent" android:id="@+id/pager" ></android.support.v4.view.ViewPager> <ImageView android:layout_width="match_parent" android:layout_height="match_parent" android:src="@mipmap/qishiye" android:id="@+id/iamge" android:visibility="gone" /> </android.support.constraint.ConstraintLayout>
package com.example.hp.myapplication; import android.content.Context; import android.os.Environment; import java.io.File; import java.math.BigDecimal; /** * Created by hp on 2017/9/17. */ public class Dataclean { public static String getTotalCacheSize(Context context) throws Exception { long cacheSize = getFolderSize(context.getCacheDir()); if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) { cacheSize += getFolderSize(context.getExternalCacheDir()); } return getFormatSize(cacheSize); } // 获取文件 //Context.getExternalFilesDir() --> SDCard/Android/data/你的应用的包名/files/ 目录,一般放一些长时间保存的数据 //Context.getExternalCacheDir() --> SDCard/Android/data/你的应用包名/cache/目录,一般存放临时缓存数据 public static long getFolderSize(File file) throws Exception { long size = 0; try { File[] fileList = file.listFiles(); for (int i = 0; i < fileList.length; i++) { // 如果下面还有文件 if (fileList[i].isDirectory()) { size = size + getFolderSize(fileList[i]); } else { size = size + fileList[i].length(); } } } catch (Exception e) { e.printStackTrace(); } return size; } public static void clearAllCache(Context context) { deleteDir(context.getCacheDir()); if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) { deleteDir(context.getExternalCacheDir()); } } private static boolean deleteDir(File dir) { if(dir == null){ return false; } if (dir != null && dir.isDirectory()) { String[] children = dir.list(); for (int i = 0; i < children.length; i++) { boolean success = deleteDir(new File(dir, children[i])); if (!success) { return false; } } } return dir.delete(); } /** * 格式化单位 * * @param size * @return */ public static String getFormatSize(double size) { double kiloByte = size / 1024; if (kiloByte < 1) { // return size + "Byte"; return "0K"; } double megaByte = kiloByte / 1024; if (megaByte < 1) { BigDecimal result1 = new BigDecimal(Double.toString(kiloByte)); return result1.setScale(2, BigDecimal.ROUND_HALF_UP) .toPlainString() + "KB"; } double gigaByte = megaByte / 1024; if (gigaByte < 1) { BigDecimal result2 = new BigDecimal(Double.toString(megaByte)); return result2.setScale(2, BigDecimal.ROUND_HALF_UP) .toPlainString() + "MB"; } double teraBytes = gigaByte / 1024; if (teraBytes < 1) { BigDecimal result3 = new BigDecimal(Double.toString(gigaByte)); return result3.setScale(2, BigDecimal.ROUND_HALF_UP) .toPlainString() + "GB"; } BigDecimal result4 = new BigDecimal(teraBytes); return result4.setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString() + "TB"; } /** * 清除本应用内部缓存(/data/data/com.xxx.xxx/cache) * * @param context */ public static void cleanInternalCache(Context context) { deleteFilesByDirectory(context.getCacheDir()); } /** * 清除本应用所有数据库(/data/data/com.xxx.xxx/databases) * * @param context */ public static void cleanDatabases(Context context) { deleteFilesByDirectory(new File("/data/data/" + context.getPackageName() + "/databases")); } /** * * 清除本应用SharedPreference(/data/data/com.xxx.xxx/shared_prefs) * * @param * context */ public static void cleanSharedPreference(Context context) { deleteFilesByDirectory(new File("/data/data/" + context.getPackageName() + "/shared_prefs")); } /** * 按名字清除本应用数据库 * * @param context * @param dbName */ public static void cleanDatabaseByName(Context context, String dbName) { context.deleteDatabase(dbName); } /** * 清除/data/data/com.xxx.xxx/files下的内容 * * @param context */ public static void cleanFiles(Context context) { deleteFilesByDirectory(context.getFilesDir()); } /** * * 清除外部cache下的内容(/mnt/sdcard/android/data/com.xxx.xxx/cache) * * @param * context */ public static void cleanExternalCache(Context context) { if (Environment.getExternalStorageState().equals( Environment.MEDIA_MOUNTED)) { deleteFilesByDirectory(context.getExternalCacheDir()); } } /** * 清除自定义路径下的文件,使用需小心,请不要误删。而且只支持目录下的文件删除 * * @param filePath */ public static void cleanCustomCache(String filePath) { deleteFilesByDirectory(new File(filePath)); } /** * 清除本应用所有的数据 * * @param context * @param filepath */ public static void cleanApplicationData(Context context, String... filepath) { cleanInternalCache(context); cleanExternalCache(context); cleanDatabases(context); cleanSharedPreference(context); cleanFiles(context); for (String filePath : filepath) { cleanCustomCache(filePath); } } /** * 删除方法 这里只会删除某个文件夹下的文件,如果传入的directory是个文件,将不做处理 * * @param directory */ private static void deleteFilesByDirectory(File directory) { if (directory != null && directory.exists() && directory.isDirectory()) { for (File item : directory.listFiles()) { item.delete(); } } } }
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