您可以创建一个类环境SDCardCheck
package com.example.storagecheck;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Build;
import android.os.Environment;
import android.os.storage.StorageManager;
import android.support.v4.content.ContextCompat;
import android.support.v4.os.EnvironmentCompat;
import android.util.Log;
import java.io.File;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
public class EnvironmentSDCardCheck {
private static final String TAG = "EnvironmentSDCardCheck";
public final static String TYPE_PRIMARY = "primär";
public final static String TYPE_INTERNAL = "intern";
public final static String TYPE_SD = "MicroSD";
public final static String TYPE_USB = "USB";
public final static String TYPE_UNKNOWN = "unbekannt";
public final static String WRITE_NONE = "none";
public final static String WRITE_READONLY = "readonly";
public final static String WRITE_APPONLY = "apponly";
public final static String WRITE_FULL = "readwrite";
private static Device[] devices, externalstorage, storage;
private static BroadcastReceiver receiver;
private static boolean useReceiver = true;
private static String userDir;
public static Device[] getDevices(Context context) {
if (devices == null) initDevices(context);
return devices;
}
public static Device[] getExternalStorage(Context context) {
if (devices == null) initDevices(context);
return externalstorage;
}
public static Device[] getStorage(Context context) {
if (devices == null) initDevices(context);
return storage;
}
public static IntentFilter getRescanIntentFilter() {
IntentFilter filter = new IntentFilter();
filter.addAction(Intent.ACTION_MEDIA_BAD_REMOVAL);
filter.addAction(Intent.ACTION_MEDIA_MOUNTED);
filter.addAction(Intent.ACTION_MEDIA_REMOVED);
filter.addAction(Intent.ACTION_MEDIA_SHARED);
filter.addDataScheme("file");
return filter;
}
public static void setUseReceiver(Context context, boolean use) {
if (use && receiver == null) {
receiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
Log.i(TAG, "Storage " + intent.getAction() + "-" + intent.getData());
initDevices(context);
}
};
context.registerReceiver(receiver, getRescanIntentFilter());
} else if (!use && receiver != null) {
context.unregisterReceiver(receiver);
receiver = null;
}
useReceiver = use;
}
public static void initDevices(Context context) {
if (userDir == null) userDir = "/Android/data/" + context.getPackageName();
setUseReceiver(context, useReceiver);
StorageManager sm = (StorageManager) context.getSystemService(Context.STORAGE_SERVICE);
Class c = sm.getClass();
Object[] vols;
try {
Method m = c.getMethod("getVolumeList", null);
vols = (Object[]) m.invoke(sm, null); // android.os.Storage.StorageVolume
Device[] temp = new Device[vols.length];
for (int i = 0; i < vols.length; i++) temp[i] = new Device(vols[i]);
Device primary = null;
for (Device d : temp) if (d.mPrimary) primary = d;
if (primary == null) for (Device d : temp)
if (!d.mRemovable) {
d.mPrimary = true;
primary = d;
break;
}
if (primary == null) {
primary = temp[0];
primary.mPrimary = true;
}
File[] files = ContextCompat.getExternalFilesDirs(context, null);
File[] caches = ContextCompat.getExternalCacheDirs(context);
for (Device d : temp) {
if (files != null) for (File f : files)
if (f != null && f.getAbsolutePath().startsWith(d.getAbsolutePath()))
d.mFiles = f;
if (caches != null) for (File f : caches)
if (f != null && f.getAbsolutePath().startsWith(d.getAbsolutePath()))
d.mCache = f;
}
ArrayList<Device> tempDev = new ArrayList<Device>(10);
ArrayList<Device> tempStor = new ArrayList<Device>(10);
ArrayList<Device> tempExt = new ArrayList<Device>(10);
for (Device d : temp) {
tempDev.add(d);
if (d.isAvailable()) {
tempExt.add(d);
tempStor.add(d);
}
}
Device internal = new Device(context);
tempStor.add(0, internal); // bei Storage-Alternativen immer
if (!primary.mEmulated) tempDev.add(0, internal); // bei Devices nur wenn zusätzlich
devices = tempDev.toArray(new Device[tempDev.size()]);
storage = tempStor.toArray(new Device[tempStor.size()]);
externalstorage = tempExt.toArray(new Device[tempExt.size()]);
} catch (Exception e) {
// Fallback auf normale Android-Funktionen
}
}
public static class Device extends File {
String mUserLabel, mUuid, mState, mWriteState, mType;
boolean mPrimary, mRemovable, mEmulated, mAllowMassStorage;
long mMaxFileSize;
File mFiles, mCache;
Device(Context context) {
super(Environment.getDataDirectory().getAbsolutePath());
mState = Environment.MEDIA_MOUNTED;
mFiles = context.getFilesDir();
mCache = context.getCacheDir();
mType = TYPE_INTERNAL;
mWriteState = WRITE_APPONLY;
}
@SuppressWarnings("NullArgumentToVariableArgMethod")
Device(Object storage) throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {
super((String) storage.getClass().getMethod("getPath", null).invoke(storage, null));
for (Method m : storage.getClass().getMethods()) {
if (m.getName().equals("getUserLabel") && m.getParameterTypes().length == 0 && m.getReturnType() == String.class)
mUserLabel = (String) m.invoke(storage, null); // ab Android 4.4
if (m.getName().equals("getUuid") && m.getParameterTypes().length == 0 && m.getReturnType() == String.class)
mUuid = (String) m.invoke(storage, null); // ab Android 4.4
if (m.getName().equals("getState") && m.getParameterTypes().length == 0 && m.getReturnType() == String.class)
mState = (String) m.invoke(storage, null); // ab Android 4.4
if (m.getName().equals("isRemovable") && m.getParameterTypes().length == 0 && m.getReturnType() == boolean.class)
mRemovable = (Boolean) m.invoke(storage, null); // ab Android 4.0
if (m.getName().equals("isPrimary") && m.getParameterTypes().length == 0 && m.getReturnType() == boolean.class)
mPrimary = (Boolean) m.invoke(storage, null); // ab Android 4.2
if (m.getName().equals("isEmulated") && m.getParameterTypes().length == 0 && m.getReturnType() == boolean.class)
mEmulated = (Boolean) m.invoke(storage, null); // ab Android 4.0
if (m.getName().equals("allowMassStorage") && m.getParameterTypes().length == 0 && m.getReturnType() == boolean.class)
mAllowMassStorage = (Boolean) m.invoke(storage, null); // ab Android 4.0
if (m.getName().equals("getMaxFileSize") && m.getParameterTypes().length == 0 && m.getReturnType() == long.class)
mMaxFileSize = (Long) m.invoke(storage, null); // ab Android 4.0
// getDescription (ab 4.1 mit context) liefert keine sinnvollen Werte
// getPathFile (ab 4.2) liefert keine sinnvollen Werte
// getMtpReserveSpace (ab 4.0) für diese Zwecke unwichtig
// getStorageId (ab 4.0) für diese Zwecke unwichtig
}
if (mState == null) mState = getState();
if (mPrimary)
mType = TYPE_PRIMARY;
else {
String n = getAbsolutePath().toLowerCase();
if (n.indexOf("sd") > 0)
mType = TYPE_SD;
else if (n.indexOf("usb") > 0)
mType = TYPE_USB;
else
mType = TYPE_UNKNOWN + " " + getAbsolutePath();
}
}
public String getType() {
return mType;
}
public String getAccess() {
if (mWriteState == null) {
try {
mWriteState = WRITE_NONE;
File[] root = listFiles();
if (root == null || root.length == 0)
throw new IOException("root empty/unreadable");
mWriteState = WRITE_READONLY;
File t = File.createTempFile("jow", null, getFilesDir());
//noinspection ResultOfMethodCallIgnored
t.delete();
mWriteState = WRITE_APPONLY;
t = File.createTempFile("jow", null, this);
//noinspection ResultOfMethodCallIgnored
t.delete();
mWriteState = WRITE_FULL;
} catch (IOException ignore) {
Log.v(TAG, "test " + getAbsolutePath() + " ->" + mWriteState + "<- " + ignore.getMessage());
}
}
return mWriteState;
}
public boolean isAvailable() {
String s = getState();
return (
Environment.MEDIA_MOUNTED.equals(s) ||
Environment.MEDIA_MOUNTED_READ_ONLY.equals(s)
);
// MEDIA_SHARED: als USB freigegeben; bitte Handy auf MTP umstellen
}
public String getState() {
if (mRemovable || mState == null) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP)
// Android 5.0? Da gibts was neues
mState = Environment.getExternalStorageState(this);
else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT)
// Android 4.4? Dann dort nachfragen
mState = Environment.getStorageState(this);
else if (canRead() && getTotalSpace() > 0)
// lesbar und Größe vorhanden => gibt es
mState = Environment.MEDIA_MOUNTED;
else if (mState == null || Environment.MEDIA_MOUNTED.equals(mState))
// nicht lesbar, keine Größe aber noch MOUNTED || oder ungesetzt => UNKNOWN
mState = EnvironmentCompat.MEDIA_UNKNOWN;
}
return mState;
}
public File getFilesDir() {
if (mFiles == null) {
mFiles = new File(this, userDir + "/files");
if (!mFiles.isDirectory())
//noinspection ResultOfMethodCallIgnored
mFiles.mkdirs();
}
return mFiles;
}
public File getCacheDir() {
if (mCache == null) {
mCache = new File(this, userDir + "/cache");
if (!mCache.isDirectory())
//noinspection ResultOfMethodCallIgnored
mCache.mkdirs();
}
return mCache;
}
public boolean isPrimary() {
return mPrimary;
}
public boolean isRemovable() {
return mRemovable;
}
public boolean isEmulated() {
return mEmulated;
}
public boolean isAllowMassStorage() {
return mAllowMassStorage;
}
public long getMaxFileSize() {
return mMaxFileSize;
}
public String getUserLabel() {
return mUserLabel;
}
public String getUuid() {
return mUuid;
}
}
}
然后您可以使用它来检查SD卡或USB或未知当前是否与设备连接
通过这种方式,您可以获得连接的SD卡,USB等。
private boolean checkSdCardPermission() {
boolean flag = false;
try {
EnvironmentSDCard.Device[] devices = EnvironmentSDCard.getExternalStorage(MainActivity.this);
for (EnvironmentSDCard.Device d : devices) {
if (d.getType().equals(EnvironmentSDCard.TYPE_SD) || d.getType().contains(EnvironmentSDCard.TYPE_UNKNOWN) || d.getType().contains(EnvironmentSDCard.TYPE_USB)) {
flag = d.isAvailable();
if (flag)
break;
}
}
} catch (Exception e) {
}
return flag;
}