Is it safe to use this constructor `Fragment(int ...

# android

[pollux-]

Is it safe to use this constructor

Fragment(int layout)

I'm getting couldn't find fragment constructor, I'm suspecting this guy.. 😭

But I also see it's call super().

I have HomeFragment which extends the BaseFragment.
Is that because of that .

[Ian Lake]

Your class that extends Fragment can use the Fragment(int layout) constructor in its zero argument constructor to set the default layout.

[Ian Lake]

Or you can have BaseFragment(@LayoutRes layout: Int = 0) and HomeFragment : BaseFragment(R.layout.fragment_home)

[Ryan]

I have given up on “base” fragments.

[Ryan]

I just extensions if need be.

[Ian Lake]

The docs explicitly tell you how you can use that constructor: https://developer.android.com/reference/kotlin/androidx/fragment/app/Fragment#init_1

[pollux-]

screen_shot_2020-11-03_at_10.24.20_am.png,screen_shot_2020-11-03_at_10.24.32_am.png,screen_shot_2020-11-03_at_10.24.49_am.png

[pollux-]

We need a default value

[pollux-]

That's the problem @Ian Lake

[pollux-]

Then when Fragment restoration happens, how exactly my UI going to looks like? 🤭
We are defaulting to 0

[Ian Lake]

As long as the fragment you're adding to the FragmentManager is passing a non-zero layout ID from its zero argument constructor, that's what you'll be using every time that fragment is created

[Ian Lake]

Since you never add a plain old BaseFragment to the FragmentManager (but only subtypes), it doesn't matter if BaseFragment has a zero argument constructor

[pollux-]

How can I test my fix?

adb shell am send-trim-memory or logcat terminate application? @Ian Lake

[pollux-]

How do you test that usually 😌

[Ian Lake]

Rotate your device? Turn on 'Don't keep activities'?

[pollux-]

I was over thinking .. let me try 🤭

[pollux-]

Not able to reproduce .. it didn't crash

[pollux-]

😭

[Ian Lake]

If your HomeFragment has a zero arg constructor like the image you shared has, no, that won't crash, no matter what your BaseFragment does or what constructor it has or calls

[pollux-]

Then why did I got this crash

[pollux-]

Couldn't find fragment constructor this is the exception I'm getting if I go with what is there in screenshot

[pollux-]

I was thinking because of we are passing layout in the Fragment constructor

[Ian Lake]

Clearly there is a zero argument constructor since you call HomeFragment()

[pollux-]

I decompiled it .. I did see a public constructor ..👍

[pollux-]

How can I fix this crash?

[pollux-]

How can I reproduce this crash?

[pollux-]

I'm lost in the woods

[Ian Lake]

Fragments is a deterministic system - it either always crashes with the same inputs or never crashes. A fragment with a public zero argument constructor can't fail with an error saying there is no public zero argument constructor 🤷

[pollux-]

@Ian Lake what about custom view in a layout .. will that cause any issues?

[Ian Lake]

That seems unrelated to fragments, fragment constructors, or state restoration of fragments

[pollux-]

Why I thought like that because, that also has overloaded constructors .. anyway thanks @Ian Lake you have so far been very helpful 😎👍🙏

[Ian Lake]

I hope you're able to figure out what went wrong / reproduce it

[pollux-]

Today was a tiring day 🤣 I'll check that tmrw