activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
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:id="@+id/root_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="16dp"
android:orientation="vertical"
android:background="#bde295"
>
<ListView
android:id="@+id/list_view"
android:layout_width="wrap_content"
android:layout_height="match_parent"
/>
</LinearLayout>
MainActivity.java
package com.cfsuman.me.androidcodesnippets;
import android.Manifest;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.ContentResolver;
import android.content.Context;
import android.content.DialogInterface;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.net.Uri;
import android.os.Build;
import android.provider.MediaStore;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ArrayAdapter;
import android.widget.LinearLayout;
import android.widget.ListView;
import java.util.HashMap;
public class MainActivity extends AppCompatActivity {
private Context mContext;
private Activity mActivity;
private LinearLayout mRootLayout;
private ListView mListView;
private static final int MY_PERMISSION_REQUEST_CODE = 123;
private HashMap<Long,String> mAudioMap = new HashMap<>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Get the application context
mContext = getApplicationContext();
mActivity = MainActivity.this;
// Get the widget reference from xml layout
mRootLayout = findViewById(R.id.root_layout);
mListView = findViewById(R.id.list_view);
// Custom method to check permission at run time
checkPermission();
}
// Custom method to get all audio files list from external storage
protected void getMusicFilesList(){
// Get the content resolver
ContentResolver contentResolver = mContext.getContentResolver();
// Get the external storage uri of media store audio
Uri uri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
/*
String IS_MUSIC
Non-zero if the audio file is music
Type: INTEGER (boolean)
*/
// Query string to filter music files only
// Remove ringtone, notification etc sound from the list
String selectionString = MediaStore.Audio.Media.IS_MUSIC + "!=0";
// Query string to sort musics by date added
String sortString = MediaStore.Audio.Media.DATE_ADDED;
// Query the media store for music files only
Cursor cursor = contentResolver.query(
uri, // Uri
null, // Projection
selectionString, // Selection
null, // Selection args
sortString // Sort order
);
if (cursor == null) {
// Query failed, handle error
} else if (!cursor.moveToFirst()) {
// No media on the device
} else {
int title = cursor.getColumnIndex(MediaStore.Audio.Media.TITLE);
int id = cursor.getColumnIndex(MediaStore.Audio.Media._ID);
// Loop through the musics
do {
// Get the current audio file id
long thisId = cursor.getLong(id);
// Get the current audio title
String thisTitle = cursor.getString(title);
// Process current music here
mAudioMap.put(thisId,thisTitle);
} while (cursor.moveToNext());
}
// Get the values array from hash map
String[] titlesArray = mAudioMap.values().toArray(new String[mAudioMap.size()]);
// Initialize an array adapter
ArrayAdapter adapter = new ArrayAdapter(
mContext, // Context
android.R.layout.simple_list_item_1, // Item layout
titlesArray // Data source
);
// Data bind list view with array adapter
mListView.setAdapter(adapter);
}
// Custom method to check and grant permission at run time
protected void checkPermission(){
if(Build.VERSION.SDK_INT>=Build.VERSION_CODES.M){
if(checkSelfPermission(Manifest.permission.READ_EXTERNAL_STORAGE)!= PackageManager.PERMISSION_GRANTED){
if(shouldShowRequestPermissionRationale(Manifest.permission.READ_EXTERNAL_STORAGE)){
// Show an alert dialog
AlertDialog.Builder builder = new AlertDialog.Builder(mActivity);
builder.setMessage("Read external storage permission is required.");
builder.setTitle("Please grant permission");
builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
ActivityCompat.requestPermissions(
mActivity,
new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},
MY_PERMISSION_REQUEST_CODE
);
}
});
builder.setNeutralButton("Cancel",null);
AlertDialog dialog = builder.create();
dialog.show();
}else {
// Request permission
ActivityCompat.requestPermissions(
mActivity,
new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},
MY_PERMISSION_REQUEST_CODE
);
}
}else {
// Permission already granted
getMusicFilesList();
}
}else {
// Permission granted by manifest file
getMusicFilesList();
}
}
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults){
switch(requestCode){
case MY_PERMISSION_REQUEST_CODE:{
if(grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED){
// Permission granted
getMusicFilesList();
}else {
// Permission denied
}
}
}
}
}
AndroidManifest.xml [Permission]
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
