【Kotlin】以 OkHttp3 偵測是否有網際網路連線能力

參考資料 ----

OkHttp

OkHttp 是輕量型的 3rd party library，這篇筆記只是記錄透過 OkHttp 偵測 Android 裝置是否有連上網際網路。

上網比較了幾個網站，選定目標網站是網頁內容(html 字數，包含 CSS, javascript...) 最少的 example.com。

app 層級的 build.gradle

 
...
...

android {
    ...
    ...
    
    buildFeatures {
            viewBinding true
    }
    
    buildTypes {
        ...
        ...
    }
    
}

...
...

dependencies {
    ...
    ...
    implementation 'com.squareup.okhttp3:okhttp:4.7.2'
}
 

AndroidManifest.xml

 

<uses-permission android:name="android.permission.INTERNET"/>

<application
    ...
    ...
    
 

activity_main.xml

 
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
    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"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/lblHello"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/btnCheck"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="check internet"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.064"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.023"
        android:onClick="onBtnClicked"/>

</androidx.constraintlayout.widget.ConstraintLayout>
 

MainActivity.kt

 
...
...

import android.os.Bundle
import android.util.Log
import android.view.View
import androidx.appcompat.app.AppCompatActivity
import com.example.okhp.databinding.ActivityMainBinding
import okhttp3.*
import okio.IOException


class MainActivity : AppCompatActivity() {

    val TAG = "MyTag"
    private lateinit var binding: ActivityMainBinding
    private lateinit var client: OkHttpClient

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityMainBinding.inflate(layoutInflater)
        val view = binding.root
        setContentView(view)
    }


    fun onBtnClicked(vv: View) {
        val client = OkHttpClient()
        val request = Request.Builder()
            .url("https://example.com")
            .build()

        client.newCall(request).enqueue(object : Callback {
            override fun onResponse(call: Call, response: Response) {
                // Log.d(TAG, "response: ${response.body?.string()}")
                runOnUiThread {
                    binding.lblHello.text = "connected"
                }
            }

            override fun onFailure(call: Call, e: IOException) {
                // Log.d(TAG, e.toString())
                runOnUiThread {
                    binding.lblHello.text = "no internet"
                }
            }
        })
    }
}
 

跟 Volley 稍微比較了一下，OkHttp3 速度確實快了一些。

相關筆記 ----

【Kotlin】視圖綁定 ViewBinding

【Kotlin】Volley -- 輕量 httpclient