Android Toast 不起作用(App 崩溃并出现 NumberFormatException)

Question

我不确定这是IDE问题还是我的编码问题。这个应用程序与我在线关注的应用程序几乎相同，但我的应用程序不断崩溃。源代码链接：https://github.com/Gusri/AgeValidated。我的代码与此几乎相同。

.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"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="min.com.nyp.sit.myapplication.MainActivity">
<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Your name" />
<EditText
    android:id="@+id/editTextName"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" />
<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Age" />
<EditText
    android:id="@+id/editTextAge"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" />
<Button
    android:id="@+id/buttonEnter"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Validate"/>
</LinearLayout>

科特林代码

   package min.com.nyp.sit.myapplication
   import android.support.v7.app.AppCompatActivity
   import android.os.Bundle
   import android.view.View
   import kotlinx.android.synthetic.main.activity_main.*
   import org.jetbrains.anko.toast
   class MainActivity : AppCompatActivity() {
   override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)
    buttonEnter.setOnClickListener({
        val age:String = editTextAge.toString()
        val Name:String = editTextName.toString()
        if (age.toInt() <= 18){
           toast("Sorry $Name your Age not Register")
        }
        else{
           toast("Thank you $Name for Register")
        }
      })
    }
  }

分级测试

buildscript {
ext.kotlin_version = '1.1.3-2'
ext.anko_version = '0.10.2'
repositories {
    google()
    jcenter()
}
dependencies {
    classpath 'com.android.tools.build:gradle:3.1.0-alpha03'
    classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    // NOTE: Do not place your application dependencies here; they belong
    // in the individual module build.gradle files
    }
 }
allprojects {
   repositories {
      google()
      jcenter()
   }
}
task clean(type: Delete) {
   delete rootProject.buildDir
}

格拉德尔应用

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'
android {
compileSdkVersion 26
buildToolsVersion "26.0.2"
defaultConfig {
    applicationId "min.com.nyp.sit.myapplication"
    minSdkVersion 26
    targetSdkVersion 26
    versionCode 1
    versionName "1.0"
    testInstrumentationRunner 
    "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
    release {
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 
       'proguard-rules.pro'
    }
   }
  }
dependencies {
  implementation fileTree(dir: 'libs', include: ['*.jar'])
  implementation 'com.android.support:appcompat-v7:26.1.0'
  implementation 'com.android.support.constraint:constraint-layout:1.0.2'
  testImplementation 'junit:junit:4.12'
  androidTestImplementation('com.android.support.test.espresso:espresso-
  core:3.0.1', {
    exclude group: 'com.android.support', module: 'support-annotations'
  })
    implementation"org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version"
    compile "org.jetbrains.anko:anko-commons:0.10.2"
  }

最后但并非最不重要的一点是，我用 anko 来展示吐司。因此，两个 gradle 脚本被修改。

这是我的堆栈跟踪：

11-11 23:14:33.319 4580-4580/min.com.nyp.sit.myapplication E/AndroidRuntime: FATAL EXCEPTION: main
 Process: min.com.nyp.sit.myapplication, PID: 4580
 java.lang.NumberFormatException: For input string: "android.support.v7.widget.AppCompatEditText{151ba00 VFED..CL. .F...... 0,290-1440,448 #7f070030 app:id/editTextAge}"
     at java.lang.Integer.parseInt(Integer.java:608)
     at java.lang.Integer.parseInt(Integer.java:643)
     at min.com.nyp.sit.myapplication.MainActivity$onCreate$1.onClick(MainActivity.kt:20)
     at android.view.View.performClick(View.java:6294)
     at android.view.View$PerformClick.run(View.java:24770)
     at android.os.Handler.handleCallback(Handler.java:790)
     at android.os.Handler.dispatchMessage(Handler.java:99)
     at android.os.Looper.loop(Looper.java:164)
     at android.app.ActivityThread.main(ActivityThread.java:6494)
     at java.lang.reflect.Method.invoke(Native Method)
     at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)

Answer 1

来自 stact teace 这是一个 NumberFormat 例外，请检查您提供输入的内容或将 EditText 限制为仅 xml 中的数字给出这样的属性

android:inputType="number"

Answer 2

您缺少从 findViewById 到 EditText 获得的视图的强制转换

var editTextName = findViewById(R.id.editTextName) as EditText
var editTextAge= findViewById(R.id.editTextAge) as EditText

然后，你想要获取编辑文本的文本属性

val age:String = editTextAge.text.toString()
val Name:String = editTextName.text.toString()
if (age.toInt() <= 18){
       toast("Sorry $Name your Age not Register")
    }
else{
       toast("Thank you $Name for Register")
    }

确保 editTextAge 中的值表示有效的 int。

Answer 3

只需使用以下代码行：

Toast.makeText(this@YourActivity, "You clicked me.", Toast.LENGTH_SHORT).show()

在这里，您的活动是您展示祝酒词的地方。

旧安卓吐司：

Toast.makeText(YourActivity.this, "You clicked me.", Toast.LENGTH_SHORT).show()