Over the course of the last few years Android development has gone through significant changes in how we structure our apps, the language we use for development, the tooling & libraries that help us speed up our development and the improvements in testing our apps. What had not changed in all these years is the Android UI toolkit. This changes with Jetpack Compose that aims to re-imagine what Android UI development would look like using declarative programming principles. It is heavily influenced by existing web and mobile frameworks such as React, Litho, Vue & Flutter and would be a paradigm shift in Android UI development as we know it.
This repository aims to show the Jetpack Compose way of building common Android UI that we are accustomed to building.
To try out this sample app, you need to at least use the Canary version of Android Studio 4.2, specifically Android Studio 4.2 Canary 1. You can download it here. In general, Jetpack Compose requires you to use the Canary version of Android Studio.
Each example is meant to be self contained and tries to explain all the
concepts that its using with comments. Compose also comes with this
nifty feature that lets you preview each component in the IntelliJ IDE
itself. To do so, go to any of the examples examples and the click on
the preview button in the top right corner. This is possible if your
@Composable component has a corresponding @Preview method associated
with it. Look at the examples below for all this to make a bit more
sense.
| Example | Preview |
|---|---|
| How do I display text on the screen using Jetpack Compose? |  |
| How do I make a view clickable and do actions when clicked? |  |
| How do I add padding around a view? How do I add an offset to a layout? How do I enforce a layout to have a fixed aspect ratio? |
 |
| How do I add a background color to any section of the screen? Example 1 Example 2 |
  |
| How do I get FrameLayout like functionality to stack views on top of one another? | |
| How do I do animation in Jetpack Compose? Example: Rotation Animation Example: Color Change Animation |
  |
| How do styles & themes work in Jetpack Compose? How do I add dark mode capability to my app? |
 |
| Example | Preview |
|---|---|
| How do I display a list in my app? Is there a RecyclerView equivalent? |
 |
| How can I have a grid layout? |  |
| How can I build a horizontally scrollable carousel? |  |
| Example | Preview |
|---|---|
| How do I align the baseline of two views? What's the layout weight equivalent in Jetpack Compose? Example with equal weights Example with unequal weights How do I auto arrange my views similar to FlexBox? Add space between views Evenly distribute space Add space around the views Tightly packed centering of views |
 |
| How do I use constraint layouts? How do I use guidelines with constraint layouts? How do I add barriers when using constraint layouts? How do I add bias when using constraint layouts? |
 |
| Example | Preview |
|---|---|
| How do I draw using a canvas? |  |
| Example of a measuring scale component |  |
| How do I detect touch events in a custom view? |
| Example | Preview |
|---|---|
| How can I use Jetpack Compose components inside existing screens? |  |
| Example | Preview |
|---|---|
| How do I write a simple UI Test in Jetpack Compose? How do I test "Composables"? |
Author: Vinay Gaba (vinaygaba@gmail.com)
Copyright 2020 Vinay Gaba
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.