Created a wrapper for shared preference logic (#43)

* Created a wrapper for shared preference logic

* Added tests

* Extracted the interface for app preferences

* Upgraded the version of mockito-core

app/build.gradle

@@ -26,6 +26,9 @@ android {
     lintOptions {
         abortOnError false
     }
+    testOptions {
+        unitTests.returnDefaultValues = true
+    }
 }
 
 protobuf {
@@ -54,4 +57,8 @@ dependencies {
     compile 'com.squareup.retrofit2:converter-gson:2.0.0'
     compile 'com.squareup.okhttp:logging-interceptor:2.6.0'
     testCompile 'junit:junit:4.12'
+    testCompile 'org.mockito:mockito-core:1.10.19'
+    testCompile 'org.powermock:powermock-module-junit4:1.6.5'
+    testCompile 'org.powermock:powermock-api-mockito:1.6.5'
+
 }

app/src/main/java/com/omkarmoghe/pokemap/MainActivity.java

@@ -1,14 +1,11 @@
 package com.omkarmoghe.pokemap;
 
 import android.content.Intent;
-import android.content.SharedPreferences;
 import android.content.pm.PackageManager;
 import android.os.Bundle;
-import android.preference.PreferenceManager;
 import android.support.annotation.NonNull;
 import android.support.v4.app.FragmentTransaction;
 import android.support.v7.widget.Toolbar;
-import android.text.TextUtils;
 import android.util.Log;
 import android.view.Menu;
 import android.view.MenuItem;
@@ -17,30 +14,26 @@
 import com.omkarmoghe.pokemap.login.RequestCredentialsDialogFragment;
 import com.omkarmoghe.pokemap.map.MapWrapperFragment;
 import com.omkarmoghe.pokemap.settings.SettingsActivity;
+import com.omkarmoghe.pokemap.app_preferences.PokemapAppPreferences;
+import com.omkarmoghe.pokemap.app_preferences.PokemapSharedPreferences;
 
 public class MainActivity extends BaseActivity {
+    private static final String TAG = "Pokemap";
 
-    public static final String TAG = "Pokemap";
-
-    // fragments
-    private MapWrapperFragment mMapWrapperFragment;
-
-    // Preferences
-    SharedPreferences pref;
+    private PokemapAppPreferences pref;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
 
-        pref = PreferenceManager.getDefaultSharedPreferences(this);
+        pref = new PokemapSharedPreferences(this);
 
         Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
         setSupportActionBar(toolbar);
 
-        mMapWrapperFragment = MapWrapperFragment.newInstance();
         FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
-        transaction.replace(R.id.main_container, mMapWrapperFragment)
+        transaction.replace(R.id.main_container, MapWrapperFragment.newInstance())
                 .addToBackStack(null)
                 .commit();
         login();
@@ -67,15 +60,10 @@ public boolean onOptionsItemSelected(MenuItem item) {
 
 
     private void login() {
-
-        String username = pref.getString(getString(R.string.pref_username), "");
-        String password = pref.getString(getString(R.string.pref_password), "");
-
-        if (TextUtils.isEmpty(username) || TextUtils.isEmpty(password)) {
+        if (!pref.isUsernameSet() || !pref.isPasswordSet()) {
             requestLoginCredentials();
         } else {
-            Log.d(TAG, "Username: " + username);
-            nianticManager.login(username, password, this);
+            nianticManager.login(pref.getUsername(), pref.getPassword(), this);
         }
     }
 
@@ -84,24 +72,13 @@ private void requestLoginCredentials() {
                 new RequestCredentialsDialogFragment.Listener() {
                     @Override
                     public void credentialsIntroduced(String username, String password) {
-                        pref.edit().putString(getString(R.string.pref_username), username).apply();
-                        pref.edit().putString(getString(R.string.pref_password), password).apply();
-
+                        pref.setUsername(username);
+                        pref.setPassword(password);
                         login();
                     }
                 }), "request_credentials").commit();
     }
 
-    @Override
-    protected void onStart() {
-        super.onStart();
-    }
-
-    @Override
-    protected void onStop() {
-        super.onStop();
-    }
-
     @Override
     public void onBackPressed() {
         this.finish();
@@ -117,6 +94,5 @@ public void onRequestPermissionsResult(int requestCode, @NonNull String[] permis
                 }
                 break;
         }
-        //super.onRequestPermissionsResult(requestCode, permissions, grantResults);
     }
 }

app/src/main/java/com/omkarmoghe/pokemap/app_preferences/PokemapAppPreferences.java

@@ -0,0 +1,38 @@
+package com.omkarmoghe.pokemap.app_preferences;
+
+import android.support.annotation.NonNull;
+
+/**
+ * A contract which defines a user's app preferences
+ */
+public interface PokemapAppPreferences {
+    /**
+     * @return true if the username has been set
+     */
+    boolean isUsernameSet();
+
+    /**
+     * @return true if password has been set
+     */
+    boolean isPasswordSet();
+
+    /**
+     * @return the username stored or an empty @see java.lang.String
+     */
+    String getUsername();
+
+    /**
+     * @param username that should be set
+     */
+    void setUsername(@NonNull String username);
+
+    /**
+     * @param password that should be set
+     */
+    void setPassword(@NonNull String password);
+
+    /**
+     * @return the password stored or an empty @see java.lang.String
+     */
+    String getPassword();
+}

app/src/main/java/com/omkarmoghe/pokemap/app_preferences/PokemapSharedPreferences.java

@@ -0,0 +1,52 @@
+package com.omkarmoghe.pokemap.app_preferences;
+
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.preference.PreferenceManager;
+import android.support.annotation.NonNull;
+
+/**
+ * Provide convenience methods to access shared preferences
+ */
+
+public final class PokemapSharedPreferences implements PokemapAppPreferences {
+    private static final String USERNAME_KEY = "UsernameKey";
+    private static final String PASSWORD_KEY = "PasswordKey";
+
+    private final SharedPreferences sharedPreferences;
+
+    public PokemapSharedPreferences(@NonNull Context context) {
+        sharedPreferences = PreferenceManager.getDefaultSharedPreferences(context);
+    }
+
+    @Override
+    public boolean isUsernameSet() {
+        return sharedPreferences.contains(USERNAME_KEY);
+    }
+
+    @Override
+    public boolean isPasswordSet() {
+        return sharedPreferences.contains(PASSWORD_KEY);
+    }
+
+
+    @Override
+    public String getUsername() {
+        return sharedPreferences.getString(USERNAME_KEY, "");
+    }
+
+    @Override
+    public void setUsername(@NonNull String username) {
+        sharedPreferences.edit().putString(USERNAME_KEY, username).apply();
+    }
+
+    @Override
+    public void setPassword(@NonNull String password) {
+        sharedPreferences.edit().putString(PASSWORD_KEY, password).apply();
+    }
+
+    @Override
+    public String getPassword() {
+        return sharedPreferences.getString(PASSWORD_KEY, "");
+    }
+}

app/src/main/java/com/omkarmoghe/pokemap/settings/SettingsActivity.java

@@ -8,20 +8,17 @@
 
 public class SettingsActivity extends AppCompatActivity {
 
-
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_settings);
 
-        // Set toolbar
         Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
         setSupportActionBar(toolbar);
 
         if(getSupportActionBar() != null)
             getSupportActionBar().setDisplayHomeAsUpEnabled(true);
 
-        // Display the fragment as the main content.
         getFragmentManager().beginTransaction()
                 .replace(R.id.settings_content, new SettingsFragment())
                 .commit();

app/src/main/res/values/strings.xml

@@ -9,8 +9,10 @@
     <string name="pref_warning">NOTE: Do NOT use your main account for this application!
         Instead, create and use a fake Pokémon Trainer Club account with a different password and email.</string>
     <string name="pref_username">Set Username</string>
+    <string name="pref_username_key">UsernameKey</string>
     <string name="pref_default_username">John Doe</string>
     <string name="pref_password">Set Password</string>
+    <string name="pref_password_key">PasswordKey</string>
     <string name="pref_default_password">***</string>
 
     <string name="pref_cat_general">General</string>

app/src/main/res/xml/preferences.xml

@@ -9,12 +9,12 @@
             android:summary="@string/pref_warning" />
 
         <EditTextPreference
-            android:key="@string/pref_username"
+            android:key="@string/pref_username_key"
             android:title="@string/pref_username"
             android:summary="@string/pref_default_username"/>
 
         <EditTextPreference
-            android:key="@string/pref_password"
+            android:key="@string/pref_password_key"
             android:title="@string/pref_password"
             android:summary="@string/pref_default_password"
             android:inputType="textPassword" />