Inline onFocusChange kotlin

Question

I'm trying to build an inline function for setOnFocusChangeListener

This is what I got so far:

inline fun EditText.onFocusChange(crossinline hasFocus: (Boolean) -> Unit) {
    setOnFocusChangeListener(View.OnFocusChangeListener { view, b -> })
}

And I use it like this

freightTimeOfDay.onFocusChange { doSomething() }

Unfortunately though it gives me no errors, doSomething() is never called.

I'm looking for two things here:

1 - Get a param in there so I can pass it on to doSomething(). For example

freightTimeOfDay.onFocusChange { doSomething(hasFocus) }

2 - Make it work :p, as right now nothing is happening.

Update:

Seems like kotlin already has some type of inline for this

editText.setOnFocusChangeListener { view, b -> doSomething(b) }

However this isn't working for me either, doSomething(hasFocus: Boolean) is never called.

Thanks in advance!

Solution 1

Just to clarify, there isn't really a point in creating an inline method extension. This was my initial objective but I later realized that using:

editText.setOnFocusChangeListener { view, b -> doSomething(b) }

was possible, it's inline, it's pretty and no extra work is needed

Solution 2

You simply forgot to call hasFocus:

setOnFocusChangeListener(View.OnFocusChangeListener { view, b -> hasFocus(b) })
                                                                 /\/\/\/\/\

Solution 3

This is a sweet and readable syntax:

yourEditText.setOnFocusChangeListener { _, hasFocus ->
    if (hasFocus)
        showSomething()
    else
        hideSomething()
}

Comments

[R G]

Can you please tell me what is "b" here?

[xinaiz]

@R_G It's a boolean argument that indicates whether view gained focus (true) or lost focus (false)

[Aerim]

Hi! Thanks for taking the time to answer. However I don't think the answer you gave is related. The question has already been answered