如何在Android kotlin中定义EditText的最小值和最大值

Question

我想制作一个点计算器我有两个编辑文本其中一个是目标，另一个失败总共必须是40如何做到这一点？

Answer 1

MainActivity.kt

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.text.Editable
import android.text.TextWatcher
import android.util.Log
import android.widget.Toast
import kotlinx.android.synthetic.main.activity_main.*
import kotlinx.android.synthetic.main.activity_main2.*
import kotlin.math.log
class MainActivity : AppCompatActivity() {

val total: Int = 40  //Max Limit
var first : Int = 0   //for first edit text GOALS
var second : Int = 0  // For Fails 
var previous : Int = 0  //store Previous value for if user enter exceed limit
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
et1.addTextChangedListener(object : TextWatcher {
override fun afterTextChanged(s: Editable) {
if(s.toString().equals("")){
first = 0
}
else {
first = et1.text.trim().toString().toInt()
}
val temp : Int = (second + first)
if(temp>40){
et1.setText(Integer.toString(previous))
first = previous
Log.v("ABCD", "MAX Limit is 40")
} else {
Log.v("ABCD", first.toString())
}
}
override fun beforeTextChanged(s: CharSequence, start: Int,
count: Int, after: Int) {
if(et1.text.trim().toString().equals("")){
previous = 0
} else {
previous = et1.text.trim().toString().toInt()
}
}
override fun onTextChanged(s: CharSequence, start: Int,
before: Int, count: Int) {
}
})
et2.addTextChangedListener(object : TextWatcher {
override fun afterTextChanged(s: Editable) {
if(s.toString().equals("")){
second = 0
}
else {
second = et2.text.trim().toString().toInt()
}
val temp : Int = (second + first)
if(temp>40){
et2.setText(Integer.toString(previous))
second = previous
Log.v("ABCD", "MAX Limit is 40")
} else {
//et2.setText(Integer.toString(second))
Log.v("ABCD", second.toString())
}
}
override fun beforeTextChanged(s: CharSequence, start: Int,
count: Int, after: Int) {
if(et2.text.trim().toString().equals("")){
previous = 0
} else {
previous = et2.text.trim().toString().toInt()
}
}
override fun onTextChanged(s: CharSequence, start: Int,
before: Int, count: Int) {
}
})
}
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/container"
android:layout_width="match_parent"
android:orientation="vertical"
android:layout_height="match_parent"
android:paddingTop="?attr/actionBarSize">

<EditText
android:id="@+id/et1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:inputType="number"/>
<EditText
android:id="@+id/et2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:inputType="number"/>
</LinearLayout>

让我们试试。我希望你的问题能得到解决。询问您是否有任何疑问。感谢

Answer 2

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
xmlns:android="http://schemas.android.com/apk/res/android" />
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:orientation="vertical">
<TextView
android:id="@+id/goal"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="Goal"
android:textSize="40dp" />
<EditText
android:id="@+id/text1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:ems="10"
android:text="0"
android:inputType="number" />
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:orientation="vertical">
<TextView
android:id="@+id/fail"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="Fail"
android:textSize="40dp" />
<EditText
android:id="@+id/text2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:ems="10"
android:text="0"
android:inputType="number" />
</LinearLayout>

</LinearLayout>
<Button
android:id="@+id/Enter"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="Enter" />

import android.os.Bundle
import android.widget.EditText
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import kotlinx.android.synthetic.main.activity_main.*

class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
var a=0
var b=0
if (text1.text!=null)
a= Integer.parseInt(text1.getText().toString())
if (text2.text!=null)
b= Integer.parseInt(text2.getText().toString())
Enter.setOnClickListener {
if ((a + b) <= 40)
Toast.makeText(this, "OK", Toast.LENGTH_LONG).show()
else Toast.makeText(
this,
"Sum of goals and fails should be maximum 40",
Toast.LENGTH_LONG
).show()
}
}
}