package com.zdsoft.picture1202;

import android.content.DialogInterface;
import android.content.Intent;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {
    private Button bt_pic;
    private final int RC_CAMERA = 1;
    private final int RC_ALBUM = 2;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initView();
        bt_pic.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                openPictuer();
            }
        });
    }

    private void initView() {
        bt_pic = (Button) findViewById(R.id.bt_pic);
    }

    private void openPictuer() {
        AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
        builder.setTitle("請選擇");
        builder.setItems(new String[]{"相機", "相簿"}, new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                switch (which) {
                    case 0:
                        //相機
                        Intent intent_camera = new Intent("android.media.action.IMAGE_CAPTURE");
                        startActivityForResult(intent_camera, RC_CAMERA);
                        break;
                    case 1:
                        //相簿
                        Intent intent_album = new Intent(Intent.ACTION_PICK);
                        intent_album.setType("image/*");
                        startActivityForResult(intent_album,RC_ALBUM);
                        break;
                }

            }
        });
        builder.create().show();
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        switch (requestCode){
            case RC_CAMERA:
                Toast.makeText(MainActivity.this, "相機回撥", Toast.LENGTH_SHORT).show();
                break;
            case RC_ALBUM:
                Toast.makeText(MainActivity.this, "相簿回撥", Toast.LENGTH_SHORT).show();
                break;
            default:break;
        }

    }
}
 

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.zdsoft.picture1202.MainActivity">

    <Button
        android:id="@+id/bt_pic"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="選擇圖片" />
</RelativeLayout>