Added Permission example for Android M for GET_ACCOUNTS permission

app/build.gradle

@@ -20,7 +20,7 @@ android {
 }
 
 dependencies {
-    compile fileTree(dir: 'libs', include: ['*.jar'])
+    compile fileTree(include: ['*.jar'], dir: 'libs')
     testCompile 'junit:junit:4.12'
     compile 'com.android.support:appcompat-v7:23.1.1'
     compile 'io.reactivex:rxandroid:1.0.1'
@@ -32,4 +32,6 @@ dependencies {
     compile 'com.squareup.okhttp:okhttp-urlconnection:2.0.0'
     compile 'com.jakewharton:butterknife:7.0.1'
     compile 'com.jakewharton.timber:timber:2.4.2'
+    compile 'com.android.support:recyclerview-v7:23.1.1'
+    compile 'com.android.support:design:23.1.1'
 }

app/src/main/AndroidManifest.xml

@@ -1,23 +1,31 @@
 <?xml version="1.0" encoding="utf-8"?>
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
-    package="io.leftshift.sample" >
+    package="io.leftshift.sample">
 
-    <uses-permission android:name="android.permission.INTERNET"/>
+    <uses-permission android:name="android.permission.INTERNET" />
+    <uses-permission android:name="android.permission.GET_ACCOUNTS" />
 
     <application
+        android:name=".LsSampleApplication"
         android:allowBackup="true"
         android:icon="@mipmap/ic_launcher"
         android:label="@string/app_name"
-        android:theme="@style/AppTheme"
-        android:name=".LsSampleApplication">
+        android:theme="@style/AppTheme">
         <activity
-            android:name="io.leftshift.sample.activities.MainActivity"
-            android:label="@string/title_activity_main" >
+            android:name=".activities.MainActivity"
+            android:label="@string/title_activity_main" />
+        <activity
+            android:name=".activities.HomeActivity"
+            android:label="@string/app_name">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
+
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
+        <activity
+            android:name="io.leftshift.androidm.activity.AccountActivity"
+            android:label="@string/title_activity_account" />
     </application>
 
 </manifest>

app/src/main/java/io/leftshift/androidm/activity/AccountActivity.java

@@ -0,0 +1,171 @@
+package io.leftshift.androidm.activity;
+
+import android.Manifest;
+import android.accounts.Account;
+import android.accounts.AccountManager;
+import android.app.Activity;
+import android.content.DialogInterface;
+import android.content.pm.PackageManager;
+import android.support.v4.app.ActivityCompat;
+import android.support.v4.app.Fragment;
+import android.support.v4.content.ContextCompat;
+import android.support.v7.app.AppCompatActivity;
+import android.os.Bundle;
+import android.text.TextUtils;
+import android.view.Menu;
+import android.view.MenuItem;
+import android.widget.FrameLayout;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import butterknife.Bind;
+import butterknife.ButterKnife;
+import io.leftshift.androidm.fragment.AccountFragment;
+import io.leftshift.androidm.utils.Utils;
+import io.leftshift.sample.R;
+
+/**
+ * @author Akshay Mukadam
+ *         LeftShift Technologies Private Limited
+ * @since 5/12/2015
+ */
+public class AccountActivity extends BaseActivity {
+
+    // Never exceed the request code more that 250
+    private final int REQUEST_CODE_ACCOUNT_PERMISSION = 101;
+
+    // Tag name for fragment
+    private final String ACCOUNT_TAG = "Account_fragment";
+    @Bind(R.id.content_layout)
+    FrameLayout frameLayout;
+    private List<String> mList;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_account);
+        ButterKnife.bind(this);
+        mList = new ArrayList<>();
+        if (checkAccountPermission()) {
+            loadAccountsFragment();
+        }
+    }
+
+    public List<String> getAccounts() {
+        mList.clear();
+        String emailStr = "";
+        Account[] accounts = AccountManager.get(this).getAccountsByType("com.google");
+        for (Account account : accounts) {
+            emailStr = account.name;
+            if (!TextUtils.isEmpty(emailStr))
+                mList.add(emailStr);
+        }
+        return mList;
+    }
+
+    /**
+     * Check Account permission is granted or not. If permission is not granted request permission
+     * from user
+     *
+     * @return
+     */
+    private boolean checkAccountPermission() {
+        // check if permission is granted use ContextCompat for backward compatibility/
+        if (ContextCompat.checkSelfPermission(this, Manifest.permission.GET_ACCOUNTS) != PackageManager.PERMISSION_GRANTED) {
+            /**
+             * Check if permission is denied previously by user. If permission is denied educate the
+             * user why a particular permission is necessary. If app has ask permission for first time
+             * show permission directly to user. If the user has clicked on never show me this it will
+             * automatically show the message permission denied
+             */
+            if (ActivityCompat.shouldShowRequestPermissionRationale(AccountActivity.this, Manifest.permission.GET_ACCOUNTS)) {
+                showPermissionDialog(AccountActivity.this, getString(R.string.contact_permission
+                ), new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int which) {
+                        requestPermission(AccountActivity.this);
+                    }
+                }, new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int which) {
+                        Utils.showSnackBar(AccountActivity.this, getString(R.string.permission_denied), findViewById(android.R.id.content));
+                    }
+                });
+                return false;
+            }
+
+            // If app has asked permission for first time request permission directly
+            requestPermission(AccountActivity.this);
+            return false;
+        } else {
+            return true;
+        }
+
+    }
+
+    /**
+     * Request permission from user
+     *
+     * @param activity
+     */
+    private void requestPermission(AppCompatActivity activity) {
+        ActivityCompat.requestPermissions(activity, new String[]{Manifest.permission.GET_ACCOUNTS}, REQUEST_CODE_ACCOUNT_PERMISSION);
+    }
+
+    @Override
+    public boolean onCreateOptionsMenu(Menu menu) {
+        // Inflate the menu; this adds items to the action bar if it is present.
+        getMenuInflater().inflate(R.menu.menu_account, menu);
+        return true;
+    }
+
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+        // Handle action bar item clicks here. The action bar will
+        // automatically handle clicks on the Home/Up button, so long
+        // as you specify a parent activity in AndroidManifest.xml.
+        int id = item.getItemId();
+
+        //noinspection SimplifiableIfStatement
+        if (id == R.id.action_settings) {
+            return true;
+        }
+
+        return super.onOptionsItemSelected(item);
+    }
+
+    @Override
+    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
+        switch (requestCode) {
+            case REQUEST_CODE_ACCOUNT_PERMISSION:
+                // grant result will always  be either PERMISSION_GRANTED/PERMISSION_DENIED it will never be @null
+                if ((grantResults[0] == PackageManager.PERMISSION_GRANTED)) {
+                    loadAccountsFragment();
+                } else {
+                    loadAccountsFragment();
+                    Utils.showSnackBar(AccountActivity.this, getString(R.string.permission_denied), findViewById(android.R.id.content));
+                }
+                break;
+        }
+        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
+    }
+
+    private void loadAccountsFragment() {
+        /**
+         * Use TAG while commit Fragment which provides avoid the fragment to call
+         * onCreateView twice when permission is denied externally by user.By using tag we avoid
+         * creating new instance of fragment by using findFragmentByTag. A good practice we should
+         * following while using fragments in app
+         */
+        Fragment fragment = getSupportFragmentManager().findFragmentByTag(ACCOUNT_TAG);
+        if (fragment == null) {
+            fragment = new AccountFragment();
+            getSupportFragmentManager().beginTransaction().add(R.id.content_layout, fragment,
+                    ACCOUNT_TAG).commitAllowingStateLoss();
+        } else {
+            ((AccountFragment) fragment).initUi();
+        }
+    }
+
+}

app/src/main/java/io/leftshift/androidm/activity/BaseActivity.java

@@ -0,0 +1,26 @@
+package io.leftshift.androidm.activity;
+
+import android.content.Context;
+import android.content.DialogInterface;
+import android.os.Bundle;
+import android.support.v7.app.AlertDialog;
+import android.support.v7.app.AppCompatActivity;
+
+/**
+ * Created by akshay on 5/12/15.
+ */
+public class BaseActivity extends AppCompatActivity {
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+    }
+
+    protected void showPermissionDialog(Context context, String message, DialogInterface.OnClickListener
+            okClickListener, DialogInterface.OnClickListener cancelOnClickListener) {
+        new AlertDialog.Builder(context).setMessage(message).
+                setCancelable(false).setPositiveButton("Ok", okClickListener).
+                setNegativeButton("CANCEL", cancelOnClickListener)
+                .show();
+    }
+}

app/src/main/java/io/leftshift/androidm/fragment/AccountFragment.java

@@ -0,0 +1,55 @@
+package io.leftshift.androidm.fragment;
+
+import android.os.Bundle;
+import android.support.annotation.Nullable;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.ArrayAdapter;
+import android.widget.AutoCompleteTextView;
+
+import java.util.List;
+
+import butterknife.Bind;
+import butterknife.ButterKnife;
+import io.leftshift.androidm.activity.AccountActivity;
+import io.leftshift.sample.R;
+
+/**
+ * Created by akshay on 5/12/15.
+ */
+public class AccountFragment extends BaseFragment {
+
+    @Bind(R.id.auto_email_text_view)
+    AutoCompleteTextView autoCompleteTextView;
+    ArrayAdapter<String> mAdapter;
+    List<String> mList;
+
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+    }
+
+    @Nullable
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
+        View view = inflater.inflate(R.layout.fragment_account, container, false);
+        ButterKnife.bind(this, view);
+        return view;
+    }
+
+    @Override
+    public void onActivityCreated(@Nullable Bundle savedInstanceState) {
+        super.onActivityCreated(savedInstanceState);
+        initUi();
+    }
+
+    public void initUi() {
+        mList = ((AccountActivity) getActivity()).getAccounts();
+        if (mList != null) {
+            autoCompleteTextView.setThreshold(1);
+            mAdapter = new ArrayAdapter<>(getActivity(), android.R.layout.simple_list_item_1, mList);
+            autoCompleteTextView.setAdapter(mAdapter);
+        }
+    }
+}

app/src/main/java/io/leftshift/androidm/fragment/BaseFragment.java

@@ -0,0 +1,25 @@
+package io.leftshift.androidm.fragment;
+
+import android.content.Context;
+import android.content.DialogInterface;
+import android.os.Bundle;
+import android.support.v7.app.AlertDialog;
+
+/**
+ * Created by akshay on 5/12/15.
+ */
+public class BaseFragment extends android.support.v4.app.Fragment {
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+    }
+
+
+    protected void showPermissionDialog(Context context, String message, DialogInterface.OnClickListener
+            okClickListener, DialogInterface.OnClickListener cancelOnClickListener) {
+        new AlertDialog.Builder(context).setMessage(message).
+                setCancelable(false).setPositiveButton("Ok", okClickListener).
+                setNegativeButton("CANCEL", cancelOnClickListener)
+                .show();
+    }
+}

app/src/main/java/io/leftshift/androidm/utils/Utils.java

@@ -0,0 +1,45 @@
+package io.leftshift.androidm.utils;
+
+import android.content.Context;
+import android.content.Intent;
+import android.graphics.Color;
+import android.net.Uri;
+import android.provider.Settings;
+import android.support.design.widget.Snackbar;
+import android.view.View;
+import android.widget.TextView;
+
+import io.leftshift.sample.R;
+
+/**
+ * Created by akshay on 5/12/15.
+ */
+public class Utils {
+
+    public static void showSnackBar(final Context context, String message, View view) {
+        if (context != null) {
+            final Snackbar snackbar = Snackbar.make(view, message, Snackbar.LENGTH_LONG);
+            View v = snackbar.getView();
+            snackbar.setAction(R.string.app_settings, new View.OnClickListener() {
+                @Override
+                public void onClick(View v) {
+                    Intent intent = new Intent();
+                    intent.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
+                    Uri uri = Uri.fromParts("package", context.getPackageName(), null);
+                    intent.setData(uri);
+                    context.startActivity(intent);
+                }
+            });
+            v.setOnClickListener(new View.OnClickListener() {
+                @Override
+                public void onClick(View v) {
+                    snackbar.dismiss();
+                }
+            });
+            TextView textView = (TextView) v.findViewById(android.support.design.R.id.snackbar_text);
+            textView.setMaxLines(3);
+            textView.setTextColor(Color.WHITE);
+            snackbar.show();
+        }
+    }
+}