Initial commit

.gitignore

@@ -0,0 +1,9 @@
+*.iml
+.gradle
+/local.properties
+/.idea/workspace.xml
+/.idea/libraries
+.DS_Store
+/build
+/captures
+.externalNativeBuild

.idea/vcs.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+  </component>
+</project>

app/.gitignore

@@ -0,0 +1 @@
+/build

app/build.gradle

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+apply plugin: 'com.android.application'
+
+android {
+    compileSdkVersion 26
+    buildToolsVersion "26.0.0"
+    defaultConfig {
+        applicationId "com.wbrawner.simplemarkdown"
+        minSdkVersion 15
+        targetSdkVersion 26
+        versionCode 1
+        versionName "1.0"
+        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+    }
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
+        }
+    }
+}
+
+dependencies {
+    compile fileTree(dir: 'libs', include: ['*.jar'])
+    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
+        exclude group: 'com.android.support', module: 'support-annotations'
+    })
+    compile 'com.android.support:appcompat-v7:26.+'
+    compile 'com.android.support.constraint:constraint-layout:1.0.2'
+    compile 'com.android.support:design:26.+'
+    compile 'us.feras.mdv:markdownview:1.1.0'
+    compile 'com.jakewharton:butterknife:8.7.0'
+    compile 'com.android.support:support-v4:26.+'
+    testCompile 'junit:junit:4.12'
+    annotationProcessor 'com.jakewharton:butterknife-compiler:8.7.0'
+}

app/proguard-rules.pro

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+# Add project specific ProGuard rules here.
+# By default, the flags in this file are appended to flags specified
+# in /home/billy/Android/Sdk/tools/proguard/proguard-android.txt
+# You can edit the include path and order by changing the proguardFiles
+# directive in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# Add any project specific keep options here:
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile

app/src/androidTest/java/com/wbrawner/simplemarkdown/ExampleInstrumentedTest.java

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+package com.wbrawner.simplemarkdown;
+
+import android.content.Context;
+import android.support.test.InstrumentationRegistry;
+import android.support.test.runner.AndroidJUnit4;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import static org.junit.Assert.*;
+
+/**
+ * Instrumentation test, which will execute on an Android device.
+ *
+ * @see <a href="http://d.android.com/tools/testing">Testing documentation</a>
+ */
+@RunWith(AndroidJUnit4.class)
+public class ExampleInstrumentedTest {
+    @Test
+    public void useAppContext() throws Exception {
+        // Context of the app under test.
+        Context appContext = InstrumentationRegistry.getTargetContext();
+
+        assertEquals("com.wbrawner.simplemarkdown", appContext.getPackageName());
+    }
+}

app/src/main/AndroidManifest.xml

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+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.wbrawner.simplemarkdown">
+
+    <application
+        android:allowBackup="true"
+        android:icon="@mipmap/ic_launcher"
+        android:label="@string/app_name"
+        android:roundIcon="@mipmap/ic_launcher_round"
+        android:supportsRtl="true"
+        android:theme="@style/AppTheme">
+        <activity android:name=".MainActivity">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN"></action>
+                <category android:name="android.intent.category.LAUNCHER"></category>
+            </intent-filter>
+        </activity>
+        <provider
+            android:name="android.support.v4.content.FileProvider"
+            android:authorities="com.wbrawner.simplemarkdown.fileprovider"
+            android:exported="false"
+            android:grantUriPermissions="true">
+            <meta-data
+                android:name="android.support.FILE_PROVIDER_PATHS"
+                android:resource="@xml/file_paths" />
+        </provider>
+
+    </application>
+
+</manifest>

app/src/main/java/com/wbrawner/simplemarkdown/EditFragment.java

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+package com.wbrawner.simplemarkdown;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.os.Bundle;
+import android.support.annotation.Nullable;
+import android.support.v4.app.Fragment;
+import android.support.v4.content.LocalBroadcastManager;
+import android.text.Editable;
+import android.text.TextWatcher;
+import android.util.Log;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.view.WindowManager;
+import android.widget.EditText;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+
+import butterknife.BindView;
+import butterknife.ButterKnife;
+
+import static android.content.ContentValues.TAG;
+
+
+public class EditFragment extends Fragment {
+    public static final String SAVE_ACTION = "com.wbrawner.simplemarkdown.ACTION_SAVE";
+    @BindView(R.id.markdown_edit) EditText markdownEditor;
+
+    private File mTmpFile;
+
+    public EditFragment() {
+        // Required empty public constructor
+    }
+
+    @Override
+    public void onCreate(@Nullable Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        IntentFilter filter = new IntentFilter();
+        filter.addAction(SAVE_ACTION);
+        LocalBroadcastManager.getInstance(getContext()).registerReceiver(
+                new EditFragment.MarkdownBroadcastSaveReceiver(),
+                filter
+        );
+    }
+
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup container,
+                             Bundle savedInstanceState) {
+        // Inflate the layout for this fragment
+        View view = inflater.inflate(R.layout.fragment_edit, container, false);
+        ButterKnife.bind(this, view);
+        if (markdownEditor.requestFocus()) {
+            getActivity().getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE);
+        };
+        markdownEditor.addTextChangedListener(new TextWatcher() {
+            @Override
+            public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
+
+            }
+
+            @Override
+            public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
+                updatePreview(markdownEditor.getText());
+            }
+
+            @Override
+            public void afterTextChanged(Editable editable) {
+            }
+        });
+        return view;
+    }
+
+    @Override
+    public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
+        super.onViewCreated(view, savedInstanceState);
+        Log.d(TAG, "Markdown from beginning: " + markdownEditor.getText().toString());
+        BufferedReader reader = null;
+        try {
+            File tmpFile = new File(getActivity().getFilesDir() + MainActivity.getTempFileName());
+            if (tmpFile.exists()) {
+                Log.d(TAG, "Temp file size: " + tmpFile.length());
+                InputStream in = new FileInputStream(tmpFile);
+                reader = new BufferedReader(new InputStreamReader(in));
+                String line;
+                while ((line = reader.readLine()) != null) {
+                    markdownEditor.append(line);
+                    markdownEditor.append("\r\n");
+                }
+            }
+        } catch (Exception e) {
+            Log.e(TAG, "Error reading temp file: ", e);
+        } finally {
+            if (reader != null) {
+                try {
+                    reader.close();
+                } catch (IOException e) {
+                }
+            }
+        }
+        if (markdownEditor.getText().length() > 0) {
+            Log.d(TAG, "We have text");
+        } else {
+            Log.d(TAG, "Blank slate");
+        }
+        updatePreview(markdownEditor.getText());
+    }
+
+    private void updatePreview(Editable data) {
+        Log.d(TAG, "Data to send: " + data.toString());
+        Intent broadcastIntent = new Intent(PreviewFragment.PREVIEW_ACTION);
+        broadcastIntent.putExtra("markdownData", data.toString());
+        LocalBroadcastManager manager = LocalBroadcastManager.getInstance(getContext());
+        manager.sendBroadcast(broadcastIntent);
+    }
+
+    public void save(String data, String filePath) {
+        if (filePath == null)
+            filePath = MainActivity.getFilePath() + MainActivity.getFileName();
+        FileOutputStream out = null;
+        try {
+            File tmpFile = new File(filePath);
+            out = new FileOutputStream(tmpFile);
+            out.write(data.getBytes());
+        } catch (Exception e) {
+            Log.e(TAG, "Error saving temp file:", e);
+        } finally {
+            try {
+                if (out != null)
+                    out.close();
+            } catch (IOException e) {
+                Log.e(TAG, "Error closing write stream", e);
+            }
+        }
+    }
+
+    public void save(String data) {
+        save(data, null);
+    }
+
+    public void save(Editable data) {
+        save(data.toString(), null);
+    }
+
+    @Override
+    public void onPause() {
+        save(markdownEditor.getText().toString(),
+                MainActivity.getTempFilePath() + MainActivity.getFileName());
+        super.onPause();
+    }
+
+
+    private class MarkdownBroadcastSaveReceiver extends BroadcastReceiver {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            if (intent.hasExtra("fileName")) {
+                String fileName = intent.getStringExtra("fileName");
+                Log.d(TAG, "File: " + fileName);
+                save(markdownEditor.getText().toString(), fileName);
+            }
+        }
+    }
+}

app/src/main/java/com/wbrawner/simplemarkdown/MainActivity.java

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+package com.wbrawner.simplemarkdown;
+
+import android.content.DialogInterface;
+import android.content.Intent;
+import android.net.Uri;
+import android.support.design.widget.TabLayout;
+import android.support.v4.app.Fragment;
+import android.support.v4.app.FragmentManager;
+import android.support.v4.app.FragmentPagerAdapter;
+import android.support.v4.content.FileProvider;
+import android.support.v4.content.LocalBroadcastManager;
+import android.support.v4.view.ViewPager;
+import android.support.v7.app.AlertDialog;
+import android.support.v7.app.AppCompatActivity;
+import android.os.Bundle;
+import android.text.InputType;
+import android.util.Log;
+import android.view.Menu;
+import android.view.MenuItem;
+import android.widget.EditText;
+
+import java.io.File;
+
+import butterknife.BindView;
+import butterknife.ButterKnife;
+
+public class MainActivity extends AppCompatActivity {
+
+    private static final String AUTHORITY = "com.wbrawner.simplemarkdown.fileprovider";
+    private static File mFilesDir;
+    @BindView(R.id.pager) ViewPager pager;
+    @BindView(R.id.layout_tab) TabLayout tabLayout;
+
+    private static final String TAG = MainActivity.class.getSimpleName();
+    private static String fileName;
+
+    public static String getTempFileName() {
+        return "com_wbrawner_simplemarkdown_tmp.md";
+    }
+
+    public static String getFileName() {
+        if (fileName == null) {
+            return getTempFileName();
+        }
+        return fileName;
+    }
+
+    public static String getTempFilePath() {
+        return mFilesDir + File.pathSeparator + "tmp" + File.pathSeparator;
+    }
+
+    public static String getFilePath() {
+        return mFilesDir + File.pathSeparator + "saved_files" + File.pathSeparator;
+    }
+
+    public static void setFileName(String fileName) {
+        MainActivity.fileName = fileName;
+    }
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_main);
+        ButterKnife.bind(this);
+        pager.setAdapter(new EditPagerAdapter(getSupportFragmentManager()));
+        mFilesDir = getFilesDir();
+    }
+
+//    @Override
+//    public boolean onCreateOptionsMenu(Menu menu) {
+//        getMenuInflater().inflate(R.menu.menu_edit, menu);
+//        return true;
+//    }
+
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+        switch (item.getItemId()) {
+            case R.id.action_save:
+                //TODO: Create popup for file name
+                AlertDialog.Builder builder = new AlertDialog.Builder(this);
+                builder.setTitle(R.string.action_save);
+
+                final EditText input = new EditText(this);
+                input.setInputType(InputType.TYPE_CLASS_TEXT);
+                input.setHint(R.string.hint_filename);
+                builder.setView(input);
+
+                builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int which) {
+                        Intent saveIntent = new Intent(EditFragment.SAVE_ACTION);
+                        saveIntent.putExtra("fileName", input.getText());
+                        LocalBroadcastManager.getInstance(getApplicationContext())
+                                .sendBroadcast(saveIntent);
+                    }
+                });
+                builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int which) {
+                        dialog.cancel();
+                    }
+                });
+
+                builder.show();
+                break;
+            case R.id.action_share:
+                //TODO: Fix this
+                File tmpFile = new File(getFilesDir() + getTempFileName());
+                if (tmpFile.exists()) {
+                    Log.d(TAG, "Temp file size: " + tmpFile.length());
+                    Uri fileUri = FileProvider.getUriForFile(MainActivity.this, AUTHORITY, tmpFile);
+                    if (fileUri != null) {
+                        Intent shareIntent = new Intent(Intent.ACTION_SEND);
+                        shareIntent.putExtra(Intent.EXTRA_STREAM, fileUri);
+                        shareIntent.setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
+                        startActivity(shareIntent);
+                    }
+                }
+                break;
+        }
+        return super.onOptionsItemSelected(item);
+    }
+
+    public class EditPagerAdapter extends FragmentPagerAdapter {
+        private static final int FRAGMENT_EDIT = 0;
+        private static final int FRAGMENT_PREVIEW = 1;
+        private static final int NUM_PAGES = 2;
+
+        public EditPagerAdapter(FragmentManager fm) {
+            super(fm);
+        }
+
+        @Override
+        public Fragment getItem(int position) {
+            switch (position) {
+                case FRAGMENT_EDIT:
+                    return new EditFragment();
+                case FRAGMENT_PREVIEW:
+                    return new PreviewFragment();
+            }
+            return null;
+        }
+
+        @Override
+        public int getCount() {
+            return NUM_PAGES;
+        }
+
+        @Override
+        public CharSequence getPageTitle(int position) {
+            int stringId = 0;
+            switch (position) {
+                case FRAGMENT_EDIT:
+                    stringId = R.string.action_edit;
+                    break;
+                case FRAGMENT_PREVIEW:
+                    stringId = R.string.action_preview;
+                    break;
+            }
+            return getString(stringId);
+        }
+    }
+}

app/src/main/java/com/wbrawner/simplemarkdown/PreviewFragment.java

@@ -0,0 +1,63 @@
+package com.wbrawner.simplemarkdown;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.net.Uri;
+import android.os.Bundle;
+import android.support.annotation.Nullable;
+import android.support.v4.app.Fragment;
+import android.support.v4.content.LocalBroadcastManager;
+import android.util.Log;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+
+import butterknife.BindView;
+import butterknife.ButterKnife;
+import us.feras.mdv.MarkdownView;
+
+public class PreviewFragment extends Fragment {
+    private static final String TAG = PreviewFragment.class.getSimpleName();
+    @BindView(R.id.markdown_view)
+    MarkdownView markdownView;
+
+    public static final String PREVIEW_ACTION = "com.wbrawner.simplemarkdown.preview";
+
+    public PreviewFragment() {
+        // Required empty public constructor
+    }
+
+    @Override
+    public void onCreate(@Nullable Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        IntentFilter filter = new IntentFilter();
+        filter.addAction(PREVIEW_ACTION);
+        LocalBroadcastManager.getInstance(getContext()).registerReceiver(
+                new MarkdownBroadcastSender(),
+                filter
+        );
+    }
+
+    @Override
+    public View onCreateView(LayoutInflater inflater, ViewGroup container,
+                             Bundle savedInstanceState) {
+        // Inflate the layout for this fragment
+        View view = inflater.inflate(R.layout.fragment_preview, container, false);
+        ButterKnife.bind(this, view);
+        return view;
+    }
+
+    private class MarkdownBroadcastSender extends BroadcastReceiver {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            if (intent.hasExtra("markdownData")) {
+                String data = intent.getStringExtra("markdownData");
+                Log.d(TAG, "Markdown Data: " + data);
+                markdownView.loadMarkdown(data);
+            }
+        }
+    }
+
+}

app/src/main/res/layout/activity_main.xml

@@ -0,0 +1,28 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent">
+    <android.support.v4.view.ViewPager
+        android:id="@+id/pager"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent">
+        <android.support.design.widget.TabLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:id="@+id/layout_tab"
+            android:layout_gravity="top">
+            <android.support.design.widget.TabItem
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:text="@string/action_edit"
+                android:id="@+id/tab_edit" />
+            <android.support.design.widget.TabItem
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:text="@string/action_preview"
+                android:id="@+id/tab_preview" />
+        </android.support.design.widget.TabLayout>
+    </android.support.v4.view.ViewPager>
+
+</LinearLayout>

app/src/main/res/layout/fragment_edit.xml

@@ -0,0 +1,16 @@
+<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:padding="8dp"
+    tools:context="com.wbrawner.simplemarkdown.EditFragment">
+        <EditText
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:id="@+id/markdown_edit"
+            android:inputType="textMultiLine"
+            android:background="@null"
+            android:hint="@string/markdown_here"
+            android:scrollHorizontally="false" />
+
+</ScrollView>

app/src/main/res/layout/fragment_preview.xml

@@ -0,0 +1,12 @@
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    tools:context="com.wbrawner.simplemarkdown.PreviewFragment">
+
+    <us.feras.mdv.MarkdownView
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:id="@+id/markdown_view" />
+
+</FrameLayout>

app/src/main/res/menu/menu_edit.xml

@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="utf-8"?>
+<menu xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto">
+    <item
+        android:title="@string/action_save"
+        android:id="@+id/action_save"
+        android:icon="@android:drawable/ic_menu_save"
+        app:showAsAction="always" />
+    <item
+        android:title="@string/action_share"
+        android:id="@+id/action_share"
+        android:icon="@android:drawable/ic_menu_share"
+        app:showAsAction="always" />
+</menu>

app/src/main/res/menu/menu_main.xml

@@ -0,0 +1,15 @@
+<menu 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"
+    tools:context="com.wbrawner.simplemarkdown.MainActivity">
+    <item
+        android:id="@+id/action_settings"
+        android:orderInCategory="100"
+        android:title="@string/action_settings"
+        app:showAsAction="never" />
+    <item
+        android:id="@+id/action_help"
+        android:orderInCategory="100"
+        android:title="@string/action_help"
+        app:showAsAction="never" />
+</menu>

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

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <color name="colorPrimary">#3F51B5</color>
+    <color name="colorPrimaryDark">#303F9F</color>
+    <color name="colorAccent">#FF4081</color>
+</resources>

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

@@ -0,0 +1,3 @@
+<resources>
+    <dimen name="fab_margin">16dp</dimen>
+</resources>

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

@@ -0,0 +1,14 @@
+<resources>
+    <string name="app_name">Simple Markdown</string>
+    <string name="action_settings">Settings</string>
+    <string name="action_help">Help</string>
+    <string name="action_edit">Edit</string>
+    <string name="action_preview">Preview</string>
+
+    <!-- TODO: Remove or change this placeholder text -->
+    <string name="hello_blank_fragment">Hello blank fragment</string>
+    <string name="markdown_here">Markdown here...</string>
+    <string name="action_save">Save</string>
+    <string name="action_share">Share</string>
+    <string name="hint_filename">File name</string>
+</resources>

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

@@ -0,0 +1,20 @@
+<resources>
+
+    <!-- Base application theme. -->
+    <style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
+        <!-- Customize your theme here. -->
+        <item name="colorPrimary">@color/colorPrimary</item>
+        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
+        <item name="colorAccent">@color/colorAccent</item>
+    </style>
+
+    <style name="AppTheme.NoActionBar">
+        <item name="windowActionBar">false</item>
+        <item name="windowNoTitle">true</item>
+    </style>
+
+    <style name="AppTheme.AppBarOverlay" parent="ThemeOverlay.AppCompat.Dark.ActionBar" />
+
+    <style name="AppTheme.PopupOverlay" parent="ThemeOverlay.AppCompat.Light" />
+
+</resources>

app/src/main/res/xml/file_paths.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<paths xmlns:android="http://schemas.android.com/apk/res/android">
+    <files-path name="markdown_files" path="/"/>
+</paths>

app/src/test/java/com/wbrawner/simplemarkdown/ExampleUnitTest.java

@@ -0,0 +1,17 @@
+package com.wbrawner.simplemarkdown;
+
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+/**
+ * Example local unit test, which will execute on the development machine (host).
+ *
+ * @see <a href="http://d.android.com/tools/testing">Testing documentation</a>
+ */
+public class ExampleUnitTest {
+    @Test
+    public void addition_isCorrect() throws Exception {
+        assertEquals(4, 2 + 2);
+    }
+}

build.gradle

@@ -0,0 +1,23 @@
+// Top-level build file where you can add configuration options common to all sub-projects/modules.
+
+buildscript {
+    repositories {
+        jcenter()
+    }
+    dependencies {
+        classpath 'com.android.tools.build:gradle:2.3.3'
+
+        // NOTE: Do not place your application dependencies here; they belong
+        // in the individual module build.gradle files
+    }
+}
+
+allprojects {
+    repositories {
+        jcenter()
+    }
+}
+
+task clean(type: Delete) {
+    delete rootProject.buildDir
+}