Why i can not see my installed android application on my phone?

Question

I am a new in android development and i have a question.

I developed my application with Android Studio and installed it on my phone(not rooted).

I can not see it in /data/"package name".

But i can see other applications: Facebook ,Whatsapp etc.

Why? How can i install it and see it like Facebook package directory.

Thanks

Answer 1

On a system standpoint, /data refers to the system's data directory located at the root of the device's filesystem. However, on a user standpoints, it can be understood as the data directory located at the root of the external storage of your device (often, but not always, a SD card). For the system, this directory's path is different: /mnt/sdcard/data for example.

As the system's /data directory is not accessible through adb shell, ddms or any filesytem explorer on a non-rooted production device, I'm assuming that you are referring to the external storage's data directory.

• External storage

<external-storage>/data, or preferably <external-storage>/Android/data, is used to store application-related data under a directory that have the same name as your application package name (typically ext.yourbrandname.yourappname).

But your application doesn't create such a directory automatically. Your app has to create this directory if needed. Hence the fact you don't see such a directory is not an evidence that the application is not installed.

I use the code below (usually: createRootDirectory((Activity) this)) to create such directories. This code is designed for minSdkVersion="8" targetSdkVersion="19". Optimizations might exist for higher minSdkVersion, I didn't investigate in this:

public static String storagePathToAbsolutePath(String pathFromStorageRoot) {
    final StringBuffer buffer = new StringBuffer(255);

    buffer.append(Environment.getExternalStorageDirectory().getAbsolutePath());

    if (pathFromStorageRoot.charAt(0) != '/') {
        buffer.append('/');
    }

    buffer.append(pathFromStorageRoot);

    return buffer.toString();
}

public static boolean createRootDirectory(Context ctx) {
    // Constant, copied here: private static final String BASE_DIR = "/Android/data/";
    final String dataDir = storagePathToAbsolutePath(BASE_DIR + getPackageName(ctx) + "/")  
    final File f = new File(dataDir);
    return f.mkdirs();
}

Side note: using [external-storage]/Android/data/<your application package name> is a clean and interesting solution: if the user uninstalls the application, this corresponding data directory will automatically be deleted. This won't happen if <your application package name> is located anywhere else, at least with old versions of Android such as 8.

• Internal storage

/data is a system directory used to store app-related libraries, caches, etc.

It contains a data directory (so its path is /data/data/). In this one, you'll actually find one directory per installed application package:

Each and every installed package has a directory named after its package name ("ext.yourbrandname.yourappname") in the /data/data directory, for system use. Your application, whatever it is has a directory there if it is installed.

Answer 2

1. Android Will automatically create a Directory of your full Package Name if you store a file in Internal Storage.
2. Saving files in External Storage is Preferable.
3. Before Posting a Query first search in the Stack Overflow forums question as Answered Already. Similar Post Answered Already click on this Links

here is my code for you: Am reading a Picture file in res/raw folder and Writing it to Internal Storage

        package com.splash.myapp;

        import java.io.IOException;
        import java.io.InputStream;
        import java.io.OutputStream;

        import android.app.Activity;
        import android.content.Context;
        import android.os.Bundle;

        public class SavingFiles extends Activity {

            OutputStream fos;

            @Override
            protected void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                setContentView(R.layout.main_activity);
                try {
                    InputStream inputStreamObj = getResources().openRawResource(R.raw.pics);
                    fos = openFileOutput("pics.png", Context.MODE_PRIVATE);
                    final byte[] buffer = new byte[1024];
                    int bytesRead = 0;
                    while ((bytesRead = inputStreamObj.read(buffer)) > 0) {

                        fos.write(buffer);
                    }
                    inputStreamObj.close();

                } catch (Exception e) {

                    e.printStackTrace();
                } finally {
                    try {
                        fos.flush();
                        fos.close();
                    } catch (IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }

                }
            }

        }

You can check in data/data /your packageName/file