<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:orientation="vertical"

    android:layout_width="fill_parent"

    android:layout_height="fill_parent"

    >

<Button

    android:id="@+id/btn0"

    android:layout_width="fill_parent"

    android:layout_height="wrap_content"

    android:text="从相册中选择照片"

    />

  <Button

    android:id="@+id/btn1"

    android:layout_width="fill_parent"

    android:layout_height="wrap_content"

    android:text="拍照"

    />

  <ImageView

    android:id="@+id/imageID"

    android:layout_width="fill_parent"

    android:layout_height="wrap_content"

    />

</LinearLayout>

using System;

using Android.App;

using Android.Content;

using Android.Widget;

using Android.OS;

using Android.Graphics;

using System.IO;

namespace Phoot

{

    [Activity(Label = "Phoot", MainLauncher = true, Icon = "@drawable/icon")]

    public class Activity1 : Activity

    {

        public static int NONE = 0;

        public static int PHOTOHRAPH = 1;//拍照

        public static int PHOTOXZOOM = 2;//缩放

        public static int PHOTORESOULT = 3;//结果

        public static string IMAGE_UNSPECTFIED = "image/*";

        ImageView imageview = null;

        Button button0 = null;

        Button button1 = null;

        protected override void OnCreate(Bundle bundle)

        {

            base.OnCreate(bundle);

            // Set our view from the "main" layout resource

            SetContentView(Resource.Layout.Main);

            button0 = FindViewById<Button>(Resource.Id.btn0);

            button1 = FindViewById<Button>(Resource.Id.btn1);

            imageview = FindViewById<ImageView>(Resource.Id.imageID);

            button0.Click += new EventHandler(button0_Click);

            button1.Click += new EventHandler(button1_Click);

        }

        //选择照片

        void button0_Click(object sender, EventArgs e)

        {

            Intent intent = new Intent(Intent.ActionPick, null);

            //选择照片意图

            intent.SetDataAndType(

             Android.Provider.MediaStore.Images.Media.ExternalContentUri, IMAGE_UNSPECTFIED);

            StartActivityForResult(intent, PHOTOXZOOM);

        }

        //拍照

        void button1_Click(object sender, EventArgs e)

        {

            Intent intent = new Intent(Android.Provider.MediaStore.ActionImageCapture);

            string file = System.IO.Path.Combine(Android.OS.Environment.ExternalStorageDirectory.ToString(),Android.OS.Environment.DirectoryDcim.ToString()+ "/test.jpg");

            var outputFileUri = Android.Net.Uri.Parse(file);

            intent.PutExtra(Android.Provider.MediaStore.ExtraOutput,file);

            StartActivityForResult(intent, PHOTOHRAPH);

        }

        protected override void OnActivityResult(int requestCode, Result resultCode, Intent data)

        {

            if (requestCode == NONE)

            {

                return;

            }

            if (requestCode == PHOTOHRAPH)

            {

                //获取照片

                Bitmap bitmap = (Bitmap)data.Extras.Get("data");

                 Java.IO.File picture = new Java.IO.File(Android.OS.Environment.ExternalStorageDirectory.ToString()+"/"+Android.OS.Environment.DirectoryDcim.ToString() + "/test.jpg");

                  //Java.IO.FileOutputStream b = new Java.IO.FileOutputStream(picture);

                  FileStream MyFileStream1 = new FileStream(picture.ToString(), FileMode.Create);

                //保存照片

                  bitmap.Compress(Bitmap.CompressFormat.Jpeg, 100, MyFileStream1);

                if (System.IO.File.Exists(picture.ToString()))

                {

                    startPhotoZoom(Android.Net.Uri.FromFile(picture));

                }

                //startPhotoZoom

            }

            if (data == null)

            {

                return;

            }

            if (requestCode == PHOTOXZOOM)

            {

                startPhotoZoom(data.Data);

            }

            //处理结果

            if (requestCode == PHOTORESOULT)

            {

                Bundle extras = data.Extras;

                if (extras != null)

                {

                    Bitmap photo = (Bitmap)extras.GetParcelable("data");

                    //Stream stream = null;

                    //压缩文件

                    //photo.Compress(Bitmap.CompressFormat.Jpeg, 75, stream);

                    imageview.SetImageBitmap(photo);

                }

            }

                    base.OnActivityResult(requestCode, resultCode, data);

        }

        //缩放

        public void startPhotoZoom(Android.Net.Uri uri)

        {

            Intent intent = new Intent("com.android.camera.action.CROP");

            intent.SetDataAndType(uri, IMAGE_UNSPECTFIED);

            intent.PutExtra("crop", true);

            //// aspectX aspectY 是宽高的比例

            intent.PutExtra("aspectX", 1);

            intent.PutExtra("aspectY", 1);

            //// outputX outputY 是裁剪图片宽?

            intent.PutExtra("outputX", 100);

            intent.PutExtra("outputY", 100);

            intent.PutExtra("return-data", true);

            StartActivityForResult(intent, PHOTORESOULT);

        }

    }

}