Android Load Image From Camera Or Gallery 讀取照片從相機或圖片庫

利用相機拍照或從已經存在的圖片庫，讀取照片並紀錄，將其顯示在app上。
1.AndroidManifest.xml加入讀取與寫入權限

2./res/layout/activity_main.xml

3.MainActivity.java

package tw.android;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.provider.MediaStore.MediaColumns;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;

public class MainActivity extends Activity {

 private Button btnSelect;
 private ImageView ivImage;

 private int REQUEST_CAMERA = 0, SELECT_FILE = 1;
 private String selectedImagePath; // 圖片檔案位置

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  btnSelect = (Button) findViewById(R.id.btnSelectPhoto);
  ivImage = (ImageView) findViewById(R.id.ivImage);

  // 取出最後圖片檔案位置
  try {
   SharedPreferences preferencesGet = getApplicationContext()
     .getSharedPreferences("image",
       android.content.Context.MODE_PRIVATE);
   selectedImagePath = preferencesGet.getString("selectedImagePath",
     ""); // 圖片檔案位置，預設為空

   Log.i("selectedImagePath", selectedImagePath + "");

  } catch (Exception e) {
  }

  /* 選擇照片 */
  btnSelect.setOnClickListener(new OnClickListener() {

   public void onClick(View v) {
    selectImage();
   }
  });

  setImage();
 }

 /* 設定圖片 */
 private void setImage() {
  BitmapFactory.Options options = new BitmapFactory.Options();
  options.inJustDecodeBounds = false; // 不顯示照片
  BitmapFactory.decodeFile(selectedImagePath, options);
  final int REQUIRED_SIZE = 200;
  int scale = 1;
  /* 圖片縮小2倍 */
  while (options.outWidth / scale / 2 >= REQUIRED_SIZE
    && options.outHeight / scale / 2 >= REQUIRED_SIZE) {
   scale *= 2;
  }
  options.inSampleSize = scale;
  options.inJustDecodeBounds = false; // 顯示照片
  Bitmap bm = BitmapFactory.decodeFile(selectedImagePath, options);
  Log.i("selectedImagePath", selectedImagePath + "");
  ivImage.setImageBitmap(bm);// 將圖片顯示
 }

 private void selectImage() {
  final String item1, item2, item3;
  item1 = "拍一張照";
  item2 = "從圖庫選取";
  item3 = "取消";

  final CharSequence[] items = { item1, item2, item3 };

  AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
  builder.setTitle("新增照片視窗");
  builder.setItems(items, new DialogInterface.OnClickListener() {
   public void onClick(DialogInterface dialog, int item) {
    switch (item) {
    case 0: // 拍一張照
     Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
     startActivityForResult(intent, REQUEST_CAMERA);
     break;
    case 1: // 從圖庫選取
     Intent intent1 = new Intent(
       Intent.ACTION_PICK,
       android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
     intent1.setType("image/*");
     startActivityForResult(
       Intent.createChooser(intent1, "選擇開啟圖庫"),
       SELECT_FILE);
     break;
    default: // 取消
     dialog.dismiss(); // 關閉對畫框
     break;
    }

   }
  });
  builder.show();
 }

 /* 啟動選擇方式 */
 @Override
 public void onActivityResult(int requestCode, int resultCode, Intent data) {
  super.onActivityResult(requestCode, resultCode, data);

  if (resultCode == Activity.RESULT_OK) {
   if (requestCode == SELECT_FILE) // 從圖庫開啟
    onSelectFromGalleryResult(data);
   else if (requestCode == REQUEST_CAMERA) // 拍照
    onCaptureImageResult(data);
  }
 }

 /* 拍照 */
 private void onCaptureImageResult(Intent data) {
  Bitmap thumbnail = (Bitmap) data.getExtras().get("data");
  ByteArrayOutputStream bytes = new ByteArrayOutputStream();
  thumbnail.compress(Bitmap.CompressFormat.JPEG, 90, bytes);
  File destination = new File(Environment.getExternalStorageDirectory(),
    System.currentTimeMillis() + ".jpg"); // 輸出檔案名稱
  selectedImagePath = destination + ""; // 輸出檔案位置
  FileOutputStream fo;
  try {
   destination.createNewFile(); // 建立檔案
   fo = new FileOutputStream(destination); // 輸出
   fo.write(bytes.toByteArray());
   fo.close();
  } catch (FileNotFoundException e) {
   e.printStackTrace();
  } catch (IOException e) {
   e.printStackTrace();
  }

  ivImage.setImageBitmap(thumbnail); // 將圖片顯示
 }

 @SuppressWarnings("deprecation")
 private void onSelectFromGalleryResult(Intent data) {
  Uri selectedImageUri = data.getData();
  String[] projection = { MediaColumns.DATA };
  Cursor cursor = managedQuery(selectedImageUri, projection, null, null,
    null);
  int column_index = cursor.getColumnIndexOrThrow(MediaColumns.DATA);
  cursor.moveToFirst();

  selectedImagePath = cursor.getString(column_index); // 選擇的照片位置

  setImage(); // 設定圖片
 }

 /* 結束時 */
 @Override
 protected void onDestroy() {
  super.onDestroy();
  /* 紀錄圖片檔案位置 */
  SharedPreferences preferencesSave = getApplicationContext()
    .getSharedPreferences("image",
      android.content.Context.MODE_PRIVATE);
  SharedPreferences.Editor editor = preferencesSave.edit();
  editor.putString("selectedImagePath", selectedImagePath); // 紀錄最後圖片位置
  editor.commit();

  Log.i("onDestroy", "onDestroy");
 }

}

檔案下載:
https://github.com/terryyamg/loadImageFromGalleryTest
參考來源:
http://www.theappguruz.com/blog/android-take-photo-camera-gallery-code-sample/