editText get text kotlin

问题:

How to get editText in kotlin and display with toast.

var editTextHello = findViewById(R.id.editTextHello)

I tried this but shows object

Toast.makeText(this,editTextHello.toString(),Toast.LENGTH_SHORT).show()

回答1:

You're missing a cast of the View you get from findViewById to EditText:

var editTextHello = findViewById(R.id.editTextHello) as EditText

Then, you want to display the text property of the EditText in your toast:

Toast.makeText(this, editTextHello.text, Toast.LENGTH_SHORT).show()

---

For the record, this is just the more idiomatic Kotlin equivalent to calling getText() on your EditText, like you'd do it in Java:

Toast.makeText(this, editTextHello.getText(), Toast.LENGTH_SHORT).show()

回答2:

This is Kotlin, not java. You do not need to get the id of it. In kotlin, just write:

var editTextHello = editTextHello.text.toString()

use the beauty of kotlin ;-)

P.s: BTW, better to choose xml IDs like edx_hello and for the kotlin part, var editTextHello. Then you can differentiate between xml vars and kotlin vars.

回答3:

The voted answer is correct but it is not the best one for the Kotlin's world. If you're really interested in entering into this world, I'd recommend you to use extensions. From Kotlin you have kotlin-android-extensions and with it you can do this:

import kotlinx.android.synthetic.reference_to_your_view.editTextHello

and this:

Toast.makeText(this, editTextHello.text, Toast.LENGTH_SHORT).show()

please, forget about the getText()... use just this, it is more clean.

ps: read about extensions and you will see you can create your own extensions and do an even more clean usage of the Toast. Something like this:

fun Context.showToast(text: CharSequence, duration: Int = Toast.LENGTH_LONG) = Toast.makeText(this, text, duration).show()

and it being used like this through your classes:

showToast("uhuuu")

but this is beyond the scope we're talking about here.

from: https://kotlinlang.org/docs/tutorials/android-plugin.html

回答4:

Use this instead it's working fine

val obj=findViewById<EditText>(R.id.editText)
Toast.makeText(this,obj.text, Toast.LENGTH_LONG).show()

回答5:

Toast.makeText(this, editTextHello.text.toString(), Toast.LENGTH_SHORT).show()

If you make edittext as nullable then the line would be

Toast.makeText(this, editTextHello?.text.toString(), Toast.LENGTH_SHORT).show()

回答6:

In Kotlin calling .text on your EditText is fine no need to do getText or toString

Toast.makeText(this, editTextHello.text, Toast.LENGTH_SHORT).show()

with button click

button?.setOnClickListener {
        Toast.makeText(this,editText.text, Toast.LENGTH_LONG).show()
    }

Even don't need findViewById

回答7:

use editTextHello.text

  Toast.makeText(this, editTextHello.text, Toast.LENGTH_SHORT).show()

回答8:

You're missing a cast of the View you get from findViewById to EditText. But you need a "if" if the control exist then get the text:

val editText = findViewById(R.id.editText_main) as EditText
if (editText != null) {
   val showString = editText.text.toString()
   Toast.makeText(this, showString, Toast.LENGTH_SHORT).show()
}

回答9:

To maintain the standard syntax of Kotlin use

var editText: EditText = findViewById(R.id.editTextHello)