<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <Button  android:id="@+id/take_photo"  android:layout_width="match_parent"  android:layout_height="wrap_content"  android:text="Take Photo" /> <Button  android:id="@+id/get_photo"  android:layout_width="match_parent"  android:layout_height="wrap_content"  android:text="get Photo" /> <ImageView  android:id="@+id/picture"  android:layout_width="wrap_content"  android:layout_height="wrap_content"  android:layout_gravity="center_horizontal" /></LinearLayout>

import java.io.File;import java.io.IOException;import android.app.Activity;import android.content.Intent;import android.graphics.Bitmap;import android.net.Uri;import android.os.Bundle;import android.os.Environment;import android.provider.MediaStore;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.ImageView;public class MainActivity extends Activity implements OnClickListener { public static final int TAKE_PHOTO = 1; public static final int CROP_PHOTO = 2; public static final int GET_PHOTO = 3; private Button takePhoto; private Button getPhoto; private ImageView picture; private Uri headImgUri; @Override protected void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.activity_main);  takePhoto = (Button) findViewById(R.id.take_photo);  getPhoto = (Button) findViewById(R.id.get_photo);  picture = (ImageView) findViewById(R.id.picture);  takePhoto.setOnClickListener(this);  getPhoto.setOnClickListener(this); } @Override public void onClick(View v) {  switch (v.getId()) {  case R.id.take_photo:   takePhoto();   break;  case R.id.get_photo:   getPhoto();   break;  default:   break;  } } // 拍照 private void takePhoto() {  File appDir = new File(Environment.getExternalStorageDirectory(),    "/etoury/picCache");  if (!appDir.exists()) {   appDir.mkdir();  }  String fileName = "user_head" + ".jpg";  File outputImage = new File(appDir, fileName);  try {   if (outputImage.exists()) {    outputImage.delete();   }   outputImage.createNewFile();  } catch (IOException e) {   e.printStackTrace();  }  headImgUri = Uri.fromFile(outputImage);  Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");  intent.putExtra(MediaStore.EXTRA_OUTPUT, headImgUri);  startActivityForResult(intent, TAKE_PHOTO); } // 定向到圖片庫 private void getPhoto() {  Intent intent = new Intent(Intent.ACTION_PICK,    android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);  startActivityForResult(intent, GET_PHOTO); } /**  * 裁剪  */ private void crop(Uri uri) {  // 裁剪圖片意圖  Intent intent = new Intent("com.android.camera.action.CROP");  intent.setDataAndType(uri, "image/*");  // 下面這個crop=true是設置在開啟的Intent中設置顯示的VIEW可裁剪  intent.putExtra("crop", "true");  intent.putExtra("scale", true);// 去黑邊  // 裁剪框的比例，1：1  intent.putExtra("aspectX", 1);// 輸出是X方向的比例  intent.putExtra("aspectY", 1);  // 裁剪后輸出圖片的尺寸大小,不能太大500程序崩潰  intent.putExtra("outputX", 256);  intent.putExtra("outputY", 256);  // 圖片格式  /* intent.putExtra("outputFormat", "JPEG"); */  intent.putExtra("outputFormat", Bitmap.CompressFormat.JPEG.toString());  // intent.putExtra("noFaceDetection", true);// 取消人臉識別  intent.putExtra("return-data", true);// true:返回uri，false：不返回uri  // 同一個地址下 裁剪的圖片覆蓋拍照的圖片  intent.putExtra(MediaStore.EXTRA_OUTPUT, headImgUri);  startActivityForResult(intent, CROP_PHOTO); } @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) {  switch (requestCode) {  case GET_PHOTO:   if (resultCode == RESULT_OK) {    crop(data.getData());   }   break;  case TAKE_PHOTO:   if (resultCode == RESULT_OK) {    crop(headImgUri);   }   break;  case CROP_PHOTO:   if (resultCode == RESULT_OK) {    Bitmap cropbitmap = data.getParcelableExtra("data");    picture.setImageBitmap(cropbitmap);   }   break;  default:   break;  } }}