AndroidのUI - AlertDialog - liguofeng29’s blog

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >
    <Button
        android:id="@+id/alertBtn1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="setMessage()"
        android:textAllCaps="false"
        android:textSize="20dp"
        android:onClick="clickAlertBtn1" />
    <Button
        android:id="@+id/alertBtn2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="setItems()"
        android:textAllCaps="false"
        android:layout_below="@+id/alertBtn1"
        android:textSize="20dp"
        android:onClick="clickAlertBtn2" />
    <Button
        android:id="@+id/alertBtn3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="setSingleChoiceItems()"
        android:textAllCaps="false"
        android:layout_below="@+id/alertBtn2"
        android:textSize="20dp"
        android:onClick="clickAlertBtn3"/>
    <Button
        android:id="@+id/alertBtn4"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="setMultiChoiceItems()"
        android:textAllCaps="false"
        android:layout_below="@+id/alertBtn3"
        android:textSize="20dp"
        android:onClick="clickAlertBtn4"/>
    <Button
        android:id="@+id/alertBtn5"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="setView()"
        android:textAllCaps="false"
        android:layout_below="@+id/alertBtn4"
        android:textSize="20dp"
        android:onClick="clickAlertBtn5"/>
    <TextView android:id="@+id/show"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/alertBtn5"
        android:textSize="30dp"
        android:textColor="#f00"/>
</RelativeLayout>

MainActivity.java

package com.example.liguofeng.alertdialog;

import android.app.AlertDialog;
import android.content.DialogInterface;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    TextView textView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        textView = (TextView) findViewById(R.id.show);
    }
    // setMessage()
    public void clickAlertBtn1(View view) {
        AlertDialog.Builder builder = getDialog();
        builder.setMessage("AlertDialog's Message.");
        // 生成＆表示
        builder.create().show();
    }
    // setItems()
    public void clickAlertBtn2(View view) {
        AlertDialog.Builder builder = getDialog();
        final String[] items = new String[]{"JAVA", "ANDROID", "C"};
        builder.setItems(items, new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                textView.setText(items[which] + "が選択されました。");
            }
        });
        // 生成＆表示
        builder.create().show();
    }
    // setSingleChoiceItems()
    public void clickAlertBtn3(View view) {
        AlertDialog.Builder builder = getDialog();
        final String[] items = new String[]{"JAVA", "ANDROID", "C"};
        builder.setSingleChoiceItems(items, 0, new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                textView.setText(items[which] + "が選択されました。");
            }
        });
        // 生成＆表示
        builder.create().show();
    }
    // setMultiChoiceItems()
    public void clickAlertBtn4(View view) {
        AlertDialog.Builder builder = getDialog();
        final String[] items = new String[]{"JAVA", "ANDROID", "C"};
        // 第2引数の状態で選択状況がわかる
        builder.setMultiChoiceItems(items, new boolean[]{true, false, true}, null);
        // 生成＆表示
        builder.create().show();
    }
    // setView()
    public void clickAlertBtn5(View view) {
        AlertDialog.Builder builder = getDialog();
        final String[] items = new String[]{"JAVA", "ANDROID", "C"};
        ImageView images = new ImageView(this);
        images.setImageResource(R.drawable.tianxie);
        images.setScaleType(ImageView.ScaleType.FIT_CENTER);
        builder.setView(images);
        // 生成＆表示
        builder.create().show();
    }
    private AlertDialog.Builder getDialog() {
        AlertDialog.Builder builder = new AlertDialog.Builder(this)
                .setTitle("AlertDialog's Title")
                .setIcon(R.drawable.ic_launcher);

        builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                textView.setText("Cancelボタンが押されました");
            }
        });

        builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                textView.setText("OKボタンが押されました");
            }
        });

        builder.setNeutralButton("第3のボタン", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                textView.setText("第3ボタンが押されました");
            }
        });
        return builder;
    }
}