I am writing an android app that stores a lot of media files. They are开发者_开发技巧 not the type (and are far too many) to clutter up the users notification or other media directories, but they also must be user-updatable, so I can't put them in the resources. I can use getExternalFilesDir to get a path on the sdcard, but I only want to do that if the app itself is installed on the sdcard. If the app is installed internally, I want to put the media in the internal memory.
So how can I determine if my app is running in internal or external memory?
You could use PackageManager to get the ApplicationInfo, and from there check the "flags" for FLAG_EXTERNAL_STORAGE.
Here's a quick example I made to demonstrate:
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
PackageManager pm = getPackageManager();
try {
PackageInfo pi = pm.getPackageInfo("com.totsp.helloworld", 0);
ApplicationInfo ai = pi.applicationInfo;
// this only works on API level 8 and higher (check that first)
Toast
.makeText(
this,
"Value of FLAG_EXTERNAL_STORAGE:"
+ ((ai.flags & ApplicationInfo.FLAG_EXTERNAL_STORAGE) == ApplicationInfo.FLAG_EXTERNAL_STORAGE),
Toast.LENGTH_LONG).show();
} catch (NameNotFoundException e) {
// do something
}
}
Still, depending on your situation (whether or not you have all the "media" up front, or the user gets/creates it as they use the app), you may want to put it on the external storage regardless. A large size internal app is frowned upon by many users (and a lot of internal media would probably make it huge).
Here is my code for checking if app is installed on SD card:
/**
* Checks if the application is installed on the SD card.
*
* @return <code>true</code> if the application is installed on the sd card
*/
public static boolean isInstalledOnSdCard() {
Context context = MbridgeApp.getContext();
// check for API level 8 and higher
if (VERSION.SDK_INT > android.os.Build.VERSION_CODES.ECLAIR_MR1) {
PackageManager pm = context.getPackageManager();
try {
PackageInfo pi = pm.getPackageInfo(context.getPackageName(), 0);
ApplicationInfo ai = pi.applicationInfo;
return (ai.flags & ApplicationInfo.FLAG_EXTERNAL_STORAGE) == ApplicationInfo.FLAG_EXTERNAL_STORAGE;
} catch (NameNotFoundException e) {
// ignore
}
}
// check for API level 7 - check files dir
try {
String filesDir = context.getFilesDir().getAbsolutePath();
if (filesDir.startsWith("/data/")) {
return false;
} else if (filesDir.contains("/mnt/") || filesDir.contains("/sdcard/")) {
return true;
}
} catch (Throwable e) {
// ignore
}
return false;
}
To Check application is installed in SD Card or not, just do this:
ApplicationInfo io = context.getApplicationInfo();
if(io.sourceDir.startsWith("/data/")) {
//application is installed in internal memory
} else if(io.sourceDir.startsWith("/mnt/") || io.sourceDir.startsWith("/sdcard/")) {
//application is installed in sdcard(external memory)
}
精彩评论