Category: Android Development

Make a RecyclerView expand its height when new item is added //Android Dev Diary

It seems that simply using android:layout_height="wrap_content" on your RecyclerView won’t make its height automatically expand when new items are added in it.
(more…)

April 4, 2023
How to start using view binding //Android Kotlin Dev Diary
First, open your app/build.gradle file

Inside the android{} block of app/build.gradle, add the following:

buildFeatures { viewBinding = true }

Sync project with gradle files.

In your activity or fragment, define the following class-wide property:
```
private lateinit var binding: FragmentorActivityNameBinding
```
Replace the FragmentorActivityNameBinding above with the appropriate binding class name. Tip: The binding class name is based on the XML file’s name. For example, if your XML file name is activity_main.xml, the binding class name should be ActivityMainBinding. Or, if your file name is fragment_main.xml, the binding class name should be FragmentMainBinding.

In your activity, the onCreate function should look like this:
```
override fun onCreate(savedInstanceState: Bundle?) {

    super.onCreate(savedInstanceState)
    binding = ActivityMainBinding.inflate(layoutInflater)
    val view = binding.root
    setContentView(view)
}
```
Otherwise, if using view binding in a fragment, your onCreateView should look like this:
```
override fun onCreateView(
    inflater: LayoutInflater, container: ViewGroup?,
    savedInstanceState: Bundle?
): View {

    binding = FragmentMainBinding.inflate(inflater, container, false)
    binding.lifecycleOwner = viewLifecycleOwner
    binding.viewModel = mainViewModel
    return binding.root
}
```
April 1, 2023
Disable animations programmatically during instrumented tests // Android Dev Diary
When running an instrumented Android test, or “androidTest”, and you encounter the following error:
```
androidx.test.espresso.PerformException: Error performing 'scroll to' on view 'Animations or transitions are enabled on the target device.
```
It means that you need to disable animations for it to successfully run the test.

But, it can take a lot of clicks on the emulator/device screen to get to the developer settings to turn off animations!

So, for a quicker way to disable animations in the Android device during development, just enter the following commands in your Android Studio terminal:
```
adb shell settings put global window_animation_scale 0.0
adb shell settings put global transition_animation_scale 0.0
adb shell settings put global animator_duration_scale 0.0
```
January 17, 2023
Exception: No signature of method android() is applicable for argument types, Build Gradle // Dev Diary
Today I wanted to make a data class a Parcelable so that I could pass it as an argument in Navigation component.

Parcelables, though better in performance than Serializables, take more time to implement! To help us out, there’s a “kotlin-parcelize” plugin that can generate the boilerplate code for us.

There were issues though.

After applying the kotlin-parcelize plugin, I was getting the error:

'kotlin-parcelize' can't be applied together with 'kotlin-android-extensions'

So kotlin-parcelize is like a “successor” to the now deprecated 'kotlin-android-extensions' that I’m still using. So I replaced 'kotlin-android-extensions' with ‘kotlin-parcelize’.

I got another error after attempting to sync with my Gradle files:
```
org.gradle.api.GradleScriptException: A problem occurred evaluating project ':app'
[...]
Caused by: groovy.lang.MissingMethodException: No signature of method: build_54gmhuqjm83le8li4fspjsxlu.android() is applicable for argument types: (build_54gmhuqjm83le8li4fspjsxlu$_run_closure1) values: [build_54gmhuqjm83le8li4fspjsxlu$_run_closure1@3c374eea]
	at build_54gmhuqjm83le8li4fspjsxlu.run([...]\app\build.gradle:11)
```
The solution was to remove the following code from my android{} block:
```
androidExtensions {
    experimental = true
}
```
After removing that, Gradle synced successfull!

References:
Parcelable implementation generator
How to use @Parcelize now that kotlin-android-extensions is being deprecated?
January 11, 2023

Two-way data binding with StateFlow & BindingAdapters //Dev Diary

I created BindingAdapters for an EditText like so:

@BindingAdapter("android:text")
fun setText(editText: EditText, inputAmount: MutableStateFlow<Double>) {
    if (editText.text.toString() != inputAmount.value.toString()) {
        editText.setText(inputAmount.value.toString())
        editText.setSelection(editText.text.length)
    }
}

@InverseBindingAdapter(attribute = "android:text")
fun getText(editText: EditText): Double {
    if (editText.text.isEmpty()) return 0.0
    return editText.text.toString().toDouble()
}

My XML layout element looks like this:

            <com.google.android.material.textfield.TextInputEditText
                android:id="@+id/tiet_input_amount"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:hint="@string/input_hint_amount"
                android:inputType="numberDecimal"
                android:text="@={viewModel._inputAmount}" />

And in my ViewModel, the inputAmount is set up this way:

    val _inputAmount: MutableStateFlow<Double> = MutableStateFlow(0.0)
    val inputAmount: StateFlow<Double> = _inputAmount

January 7, 2023

Grant, revoke permissions via Android Studio Terminal (ADB Shell) // Android Dev Diary

To grant and revoke permissions via Terminal (ADB Shell), run your app on an emulator (I haven’t personally tried on a device but it should work there too).

Open your Terminal, and then enter the following command:

adb shell

Once you’re in, you may use the following syntax for granting or revoking your Android device’s permissions:

pm grant <package-name> <permission>

For example, to grant a permission:

pm grant net.catzie.myapp android.permission.READ_EXTERNAL_STORAGE

pm grant net.catzie.myapp android.permission.WRITE_EXTERNAL_STORAGE

And to revoke a permission:

pm revoke net.catzie.myapp android.permission.READ_EXTERNAL_STORAGE

pm revoke net.catzie.myapp android.permission.WRITE_EXTERNAL_STORAGE

Now there’s no need to open the settings screen on your device to play with your Android permissions!

December 1, 2022
Remove room database on app uninstall // Android Dev Diary

The problem:

Installing on an Android device that has an old version of an app I’m developing triggers an error:

Room Database Migration: java.lang.IllegalStateException: Migration didn't properly handle

Problem persists despite uninstalling the Android app and deleting all app data.

The solution:

Very simple. I set allowBackup to false in my AndroidManifest.xml file like so:

android:allowBackup="false"

Then I reinstalled the app on the Android device. Error was still triggered on first install, but after one more round of uninstall and reinstall, the error finally went away!

Side Note / Quick Life Update:

I have been working on an app, with me as its first user. I tentatively call it “bodymonitor”. It should let me log foods I ate, meds/supplements I took, and body sensations. My brain does not do a good job of monitoring these things so I shall get an app to help me do it. There are existing apps out there that do more or less the same thing, but I want one that caters to my specific needs. Doesn’t hurt to practice Android app development as I make the app, too!

This weekend I’ll undergo endoscopy again, but this time it’s called a “flexible nasopharyngolaryngoscopy” which will pass through the nose instead of the mouth, to be done under local anesthesia. From the sound of it I don’t expect to be put to sleep, which makes me less anxious, but still anxious. XD It’s gonna be done because of my throat issues.

November 10, 2022

Category: Android Development

The problem:

The solution:

Side Note / Quick Life Update: