display a dialog at leaving with unsaved changes

app/src/main/java/com/simplemobiletools/notes/Config.java

@@ -37,4 +37,12 @@ public class Config {
     public void setIsAutosaveEnabled(boolean enabled) {
         mPrefs.edit().putBoolean(Constants.AUTOSAVE, enabled).apply();
     }
+
+    public boolean getShouldPromptAutosave() {
+        return mPrefs.getBoolean(Constants.PROMPT_AUTOSAVE, true);
+    }
+
+    public void setShouldPromptAutosave(boolean prompt) {
+        mPrefs.edit().putBoolean(Constants.PROMPT_AUTOSAVE, prompt).apply();
+    }
 }

app/src/main/java/com/simplemobiletools/notes/Constants.java

@@ -8,6 +8,7 @@ public class Constants {
     public static final String IS_FIRST_RUN = "is_first_run";
     public static final String IS_DARK_THEME = "is_dark_theme";
     public static final String AUTOSAVE = "autosave";
+    public static final String PROMPT_AUTOSAVE = "prompt_autosave";
     public static final String WIDGET_BG_COLOR = "widget_bg_color";
     public static final String WIDGET_TEXT_COLOR = "widget_text_color";
 }

app/src/main/java/com/simplemobiletools/notes/activities/MainActivity.java

@@ -3,10 +3,12 @@ package com.simplemobiletools.notes.activities;
 import android.appwidget.AppWidgetManager;
 import android.content.ComponentName;
 import android.content.Context;
+import android.content.DialogInterface;
 import android.content.Intent;
 import android.content.SharedPreferences;
 import android.content.res.Resources;
 import android.os.Bundle;
+import android.support.v7.app.AlertDialog;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.inputmethod.InputMethodManager;
@@ -33,8 +35,7 @@ public class MainActivity extends SimpleActivity {
         ButterKnife.bind(this);
 
         mPrefs = getSharedPreferences(Constants.PREFS_KEY, Context.MODE_PRIVATE);
-        final String text = mPrefs.getString(Constants.TEXT, "");
+        mNotesView.setText(getSavedNote());
-        mNotesView.setText(text);
     }
 
     @Override
@@ -51,6 +52,16 @@ public class MainActivity extends SimpleActivity {
         }
     }
 
+    @Override
+    public void onBackPressed() {
+        if (mConfig.getShouldPromptAutosave() && !getCurrentNote().equals(getSavedNote())) {
+            mConfig.setShouldPromptAutosave(false);
+            displayAutosavePrompt();
+        } else {
+            super.onBackPressed();
+        }
+    }
+
     @Override
     protected void onDestroy() {
         super.onDestroy();
@@ -86,8 +97,23 @@ public class MainActivity extends SimpleActivity {
         }
     }
 
+    private void displayAutosavePrompt() {
+        final AlertDialog.Builder alertDialog = new AlertDialog.Builder(this);
+        alertDialog.setTitle(getString(R.string.unsaved_changes));
+        alertDialog.setMessage(getString(R.string.autosave_prompt_msg));
+
+        alertDialog.setNegativeButton(R.string.cancel, null);
+        alertDialog.setPositiveButton(R.string.enable_autosave, new DialogInterface.OnClickListener() {
+            @Override
+            public void onClick(DialogInterface dialog, int which) {
+
+            }
+        });
+        alertDialog.create().show();
+    }
+
     private void saveText(boolean showToast) {
-        final String text = mNotesView.getText().toString().trim();
+        final String text = getCurrentNote();
         mPrefs.edit().putString(Constants.TEXT, text).apply();
 
         if (showToast) {
@@ -99,7 +125,7 @@ public class MainActivity extends SimpleActivity {
     }
 
     private void shareText() {
-        final String text = mNotesView.getText().toString().trim();
+        final String text = getCurrentNote();
         if (text.isEmpty()) {
             Utils.showToast(getApplicationContext(), R.string.cannot_share_empty_text);
             return;
@@ -115,6 +141,14 @@ public class MainActivity extends SimpleActivity {
         startActivity(Intent.createChooser(sendIntent, shareTitle));
     }
 
+    private String getCurrentNote() {
+        return mNotesView.getText().toString().trim();
+    }
+
+    private String getSavedNote() {
+        return mPrefs.getString(Constants.TEXT, "");
+    }
+
     private void hideKeyboard() {
         final InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
         imm.hideSoftInputFromWindow(mNotesView.getWindowToken(), 0);

app/src/main/java/com/simplemobiletools/notes/activities/SettingsActivity.java

@@ -26,6 +26,7 @@ public class SettingsActivity extends SimpleActivity {
 
         setupDarkTheme();
         setupAutosave();
+        mConfig.setShouldPromptAutosave(false);
     }
 
     private void setupDarkTheme() {

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

@@ -7,6 +7,10 @@
     <string name="cannot_share_empty_text">Impossibile condividere un testo vuoto</string>
     <string name="text_saved">Testo salvato</string>
     <string name="simple_note">Simple Note</string>
+    <string name="enable_autosave">Enable autosave</string>
+    <string name="cancel">Cancel</string>
+    <string name="unsaved_changes">Unsaved changes</string>
+    <string name="autosave_prompt_msg">Changes made to the note have not be saved. Do you want to enable autosave?</string>
 
     <!-- Settings -->
     <string name="settings">Impostazioni</string>

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

@@ -7,6 +7,10 @@
     <string name="cannot_share_empty_text">空のテキストは共有できません</string>
     <string name="text_saved">テキストを保存しました</string>
     <string name="simple_note">シンプル メモ</string>
+    <string name="enable_autosave">Enable autosave</string>
+    <string name="cancel">Cancel</string>
+    <string name="unsaved_changes">Unsaved changes</string>
+    <string name="autosave_prompt_msg">Changes made to the note have not be saved. Do you want to enable autosave?</string>
 
     <!-- Settings -->
     <string name="settings">設定</string>

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

@@ -7,6 +7,10 @@
     <string name="cannot_share_empty_text">Det går inte att dela utan text</string>
     <string name="text_saved">Text sparad</string>
     <string name="simple_note">Simple Note</string>
+    <string name="enable_autosave">Enable autosave</string>
+    <string name="cancel">Cancel</string>
+    <string name="unsaved_changes">Unsaved changes</string>
+    <string name="autosave_prompt_msg">Changes made to the note have not be saved. Do you want to enable autosave?</string>
 
     <!-- Settings -->
     <string name="settings">Inställningar</string>

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

@@ -7,6 +7,10 @@
     <string name="cannot_share_empty_text">Cannot share empty text</string>
     <string name="text_saved">Text Saved</string>
     <string name="simple_note">Simple Note</string>
+    <string name="enable_autosave">Enable autosave</string>
+    <string name="cancel">Cancel</string>
+    <string name="unsaved_changes">Unsaved changes</string>
+    <string name="autosave_prompt_msg">Changes made to the note have not be saved. Do you want to enable autosave?</string>
 
     <!-- Settings -->
     <string name="settings">Settings</string>

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

@@ -5,7 +5,6 @@
         <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
         <item name="colorAccent">@color/colorAccent</item>
         <item name="actionBarStyle">@style/AppTheme.ActionBarStyle</item>
-        <item name="android:textSize">@dimen/normal_text_size</item>
     </style>
 
     <style name="AppTheme.Dark" parent="Theme.AppCompat">
@@ -13,7 +12,6 @@
         <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
         <item name="colorAccent">@color/colorAccent</item>
         <item name="actionBarStyle">@style/AppTheme.ActionBarStyle</item>
-        <item name="android:textSize">@dimen/normal_text_size</item>
         <item name="android:windowBackground">@android:color/black</item>
     </style>