android開発 ダイアログから呼び出し元Activityに値を渡す（Contextを利用）

2022 Apr. 29.
2022 Apr. 24.

出典　DialogFragment を利用したカスタムダイアログからActivityに値を返す | iPentec
参考　android開発 ダイアログから呼び出し元に値を渡す - rokkonet

概要

• 呼び出し元Activityに、値を取得するメソッドonReturnValue()を定義する
  
• ダイアログ内で呼び出し元のコンテクストを取得し、変数callingActivityに保持する
  (Dialogクラスのコンストラクタの引数に呼び出し元のコンテクストがセットされている)
  
• ダイアログのOKボタンのonClickイベントで、callingActivity.onReturnValue()を実行する
  
  

  build.gradle(Module: app)
  

plugins {
    id 'com.android.application'
    id 'org.jetbrains.kotlin.android'
}

android {
    compileSdk 32

    defaultConfig {
        applicationId "net.sytes.rokkosan.mypassvaluefromdialogtoactivity"
        minSdk 30
        targetSdk 32
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
    kotlinOptions {
        jvmTarget = '1.8'
    }
}

dependencies {

    implementation 'androidx.core:core-ktx:1.7.0'
    implementation 'androidx.appcompat:appcompat:1.4.1'
    implementation 'com.google.android.material:material:1.5.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.1.3'
    testImplementation 'junit:junit:4.13.2'
    androidTestImplementation 'androidx.test.ext:junit:1.1.3'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'
}

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/textViewInfo1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toTopOf="@id/buttonOpenDialog"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/buttonOpenDialog"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/button_activity_label"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toBottomOf="@id/textViewInfo1" />

</androidx.constraintlayout.widget.ConstraintLayout>

my_dialog.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">

    <TextView
        android:id="@+id/textViewGuide"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/text_view_guide"
        app:layout_constraintBottom_toTopOf="@id/editTextMessage"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/buttonOk"
        app:layout_constraintTop_toTopOf="parent" />

    <EditText
        android:id="@+id/editTextMessage"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:ems="10"
        android:inputType="textPersonName"
        app:layout_constraintBottom_toTopOf="@id/buttonOk"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/textViewGuide" />

    <Button
        android:id="@+id/buttonOk"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/button_dialog_label"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/editTextMessage" />
</androidx.constraintlayout.widget.ConstraintLayout>

MainActivity.kt

package net.sytes.rokkosan.mypassvaluefromdialogtoactivity

/*
2022 Apr. 24.
Ryuichi Hashimoto.
This is a copy of the codes in https://www.ipentec.com/document/android-custom-dialog-using-dialogfragment-return-value
*/

import android.os.Bundle
import android.widget.Button
import android.widget.TextView
import androidx.appcompat.app.AppCompatActivity

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val buttonOpenDialog = findViewById<Button>(R.id.buttonOpenDialog)
        buttonOpenDialog.setOnClickListener { showMyDialog() }
    }

    private fun showMyDialog() {
        val cdf = CustomDialogFragment()
        cdf.show(supportFragmentManager, "dialog")
    }

    public fun onReturnValue(value: String) {
        val textViewInfo1 = findViewById<TextView>(R.id.textViewInfo1)
        textViewInfo1.text = value
    }
}

CustomDialogFragment.kt

package net.sytes.rokkosan.mypassvaluefromdialogtoactivity

/*
2022 Apr. 28.
2022 Apr. 24.
Ryuichi Hashimoto.
This is a copy of the codes in https://www.ipentec.com/document/android-custom-dialog-using-dialogfragment-return-value
*/

import android.app.Dialog
import android.os.Bundle
import android.view.Window
import android.widget.Button
import android.widget.EditText
import androidx.fragment.app.DialogFragment

class CustomDialogFragment : DialogFragment() {
    override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
        val myDialog = Dialog(requireContext())
        myDialog.getWindow()?.requestFeature(Window.FEATURE_NO_TITLE)
        myDialog.setContentView(R.layout.my_dialog)
        val editTextMessage = myDialog.findViewById<EditText>(R.id.editTextMessage)
        myDialog.findViewById<Button>(R.id.buttonOk).setOnClickListener {
                val text = editTextMessage.text.toString()
                val callingActivity = activity as MainActivity
                callingActivity.onReturnValue(text)
                dismiss()
        }
        return myDialog
    }
}