Depracated - use Anko by jetbrains
Android Kotlin Extensions
A collection of Kotlin extensions for Android, based on KotlinAndroidLib and Android Kotlin Extensions.
Include this library in your project
Step 1. Add the JitPack repository to your build file
repositories {
maven {
url "https://jitpack.io"
}
}
Step 2. Add the dependency in the form
dependencies {
compile 'com.github.yoavst:androidKotlin:1.5.1'
}
Activities & Services
Example: Start an Activity
Java
Intent intent = new Intent(this, SuperPowersActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);
Kotlin
val flags = flags(Intent.FLAG_ACTIVITY_NEW_TASK, Intent.FLAG_ACTIVITY_CLEAR_TOP) start<SuperPowersActivity>(flags)
Example: Create an Intent
Java
Intent intent = new Intent(this, SuperPowersActivity.class);
Kotlin
val intent = intent<SuperPowersActivity>()
Api
Java
int sdk = Build.VERSION.SDK_INT; if (sdk >= Build.VERSION_CODES.LOLLIPOP) {
}
if (sdk < Build.VERSION_CODES.LOLLIPOP) {
}
if (sdk >= Build.VERSION_CODES.KITKAT) {
}
if (sdk < Build.VERSION_CODES.KITKAT) {
}
if (sdk >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
}
if (sdk < Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
}
if (sdk >= X) {
}
if (sdk < X) {
}
Kotlin
val sdk = currentVersion() if (lollipopOrNewer()) {
}
if (beforeLollipop()) {
}
if (kitkatOrNewer()) {
}
if (beforeKitkat()) {
}
if (icsOrNewer()) {
}
if (beforeIcs()) {
}
if (versionOrNewer(x)) {
}
if (beforeVersion(x)) {
}
Async and main thread
Kotlin
async {
}
mainThread {
}
Broadcast Receiver
Java
new BroadcastReceiver() {
@Override
public void onReceive(Context context,Intent intent) {
}
}
;
Kotlin
broadcastReceiver {
context,intent ->
}
Layout Inflation
Java
LayoutInflater layoutInflater = LayoutInflater.from(this);
View awesomeView = layoutInflater.inflate(R.layout.my_awesome_layout, null);
Kotlin
val awesomeView = inflateLayout(R.layout.my_awesome_layout)
Logs
Example: Logging
Java
String tag = this.getClass().getName();
Log.i(tag, "Howdy! Info");
Log.d(tag, "Knock knock! Debug");
Log.e(tag, "Grim, Error");
Log.wtf(tag, "Damn! WTF");
// Nope, not what you think. Refer the docs :P
Kotlin
i("Howdy! Info") d("Knock knock! Debug") e("Grim, Error") wtf("Damn! WTF")
Preferences
Example: Single Preference
Java
SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(this);
Editor editor = preferences.edit();
editor.putBoolean("KEY_WALKTHROUGH_COMPLETE", complete);
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.GINGERBREAD) {
editor.commit();
}
else {
editor.apply();
}
Kotlin
getDefaultSharedPreferences().putBoolean("KEY_WALKTHROUGH_COMPLETE", complete)
Example: Bulk Preferences
Kotlin
getDefaultSharedPreferences()
.bulk()
.putBoolean("KEY_WALKTHROUGH_COMPLETE", complete)
.putString("KEY_LAST_USED", lastUsedIso8601Date)
.applyBulk()
Toasts
Example: Short Message
Java
Toast.makeText(this, R.string.welcome, Toast.LENGTH_SHORT).show();
Kotlin
toast(R.string.welcome)
Example: Long Message
Java
Toast.makeText(this, R.string.welcome, Toast.LENGTH_LONG).show();
Kotlin
longToast(R.string.welcome)
System Services
Example: System service on code
Java
AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
NotificationManager notificationManager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
Kotlin
val alarmManager = context.alarmManager() val notificationManager = context.notificationManager()
Example: System service field (lazy)
Java
AlarmManager alarmManager; NotificationManager notificationManager; public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
}
Kotlin
val alarmManager: AlarmManager by systemService() val notificationManager: NotificationManager by systemService()
Resources
Example: Typeface from Assets
Java
AssetManager assetManager = getAssets();
Typeface sourceSansPro = Typeface.createFromAsset(assetManager, "fonts/source-sans-pro.ttf");
Kotlin
val sourceSansPro = typefaceFromAssets("fonts/source-sans-pro.ttf")
Example: Get resources
Java
int number = getResources().getInteger(R.integer.number);
int dimenPixelSize = getResources().getDimensionPixelSize(R.dimen.size);
int color = getResources().getColor(R.color.red);
int[] intArray = getResources().getIntArray(R.array.ids);
String[] stringArray = getResources().getColor(R.array.options);
Drawable drawable = getResources().getDrawable(R.drawable.background);
Kotlin
val number = intRes(R.integer.number) val dimenPixelSize = dimenRes(R.dimen.size) val color = colorRes(R.color.red) val intArray = intArrayRes(R.array.ids) val stringArray = stringArrayRes(R.array.options) val drawable = drawableRes(R.drawable.background)
Example: Get resources as field (lazy)
Kotlin
val text by stringResource(R.string.text) val number by intResource(R.integer.number) val dimenPixelSize by dimenResource(R.dimen.size) val color by colorResource(R.color.red) val intArray by intArrayResource(R.array.ids) val stringArray by stringArrayResource(R.array.options) val drawable by drawableResource(R.drawable.background)
Example: DP and PX converter
Kotlin
val px = 40.toPx(context) val dp = 180.toDp(activity)
More...
More extensions under development.
License
Copyright 2015 Yoav sternberg Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.