Mercandj

import UIKit
import SwiftUI // <-- Add SwiftUI import

class HelloWorldView: UIView {

    // UIView code here
    
    struct HelloWorldView_Preview: PreviewProvider { // <-- Add the preview definition
        static var previews: some View {
            Preview()

Mercandj

import UIKit

class HelloWorldView: UIView {
  
    private lazy var title = createTitle()

    override init(frame: CGRect) {
        super.init(frame: frame)
        addSubview(title)
    }

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class MainActivity : AppCompatActivity() {

    private val listener = Manager.Listener {
        Log.d("memory_leak", "Use largeObject to avoid compiler opti $largeObject")
    }
    private var largeObject = (0..4_000).map {
        Bitmap.createBitmap(1000, 1000, Bitmap.Config.ARGB_8888)
    }

    override fun onCreate(savedInstanceState: Bundle?) {

Mercandj

Android drawing stylus performance

Goal, increase stylus performances on Android: mobile, tablet, Chromebooks...

AndroidX.graphics

Requirements: OpenGL architecture must let you draw "incrementally" (delta) or "fully"

Dependency

Mercandj

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath(kotlin("gradle-plugin", version = "1.6.21"))
    }
}

allprojects {

Mercandj

package com.medium

import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.fillMaxHeight
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.material.Text
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.dp
import androidx.compose.ui.unit.sp

Mercandj

Android: Memory leak

Java and the JVM may leak objects.

Leaking an object on Java (or Kotlin) is done when a reference direct or indirect (via transitivity) is kept so that the Garbage Collector cannot release the memory.

What	Meaning in this snippet
live	Means, cannot be garbage collected
died	Means, is garbage collected

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Fail fast

One goal of mobile apps or any dev project, is to not have crash or wrong behavior.

I. Example and "safe" implementation

Imagine a car with a car.setAccelerationPercent(Float).

For example, the client using the car can

• shut off the acceleration with car.setAccelerationPercent(0f)

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Tests from a Mobile Developer point of view

Hi 👋, I'm Jonathan, Android Lead at MWM. "You should write tests", that something we can hear on the mobile / tech industry. But the question is Why?. Let's find out if writing tests is something you should invest on.

---

"Be sure you test the tests written" 🙃. Romain Guy and Chet Haase.

Mercandj

Android developer: Principles

Description

Please, first, checkout Developer: Principles. These Android developer principles are the "implementation details" of developer principles on the Android world.

The following advices are very opinionated. Before saying "bullshit", please read the why below in the Details section. One of the main ability of developer is to understand the why. (This advice apply to myself of course. Every tool I'm criticising exist because of a why that I consider less important than the alternative. But for sure, you can disagree).

The goal of this document is more to start a reflection than make you think twice of your code.