这里有两个关于图像拾取器的有用教程，可下载源代码:

如何创建Android图像拾取器

如何在Android上选择和裁剪图像

但是，应用程序有时会被迫关闭，你可以通过添加android:configChanges属性到Manifest文件中的主活动来修复它:

<activity android:name=".MainActivity"
                  android:label="@string/app_name" android:configChanges="keyboardHidden|orientation" >

似乎相机API失去了对方向的控制，所以这将有助于它。：）

以上答案正确。我遇到了一个不同的问题，在HTC M8中，我的应用程序在从图库中选择图像时崩溃。我得到的图像路径是空值。我用以下解决方案进行了修正和优化。onActivityResult方法

protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if ((requestCode == RESULT_LOAD_IMAGE) && (resultCode == RESULT_OK)) {
     if (data != null) {

            Uri selectedImageUri = null;
            selectedImageUri = data.getData();
            String[] filePathColumn = { MediaStore.Images.Media.DATA };

            Cursor imageCursor = mainActivity.getContentResolver().query(
                    selectedImageUri, filePathColumn, null, null, null);

            if (imageCursor == null) {
                return;
            }

            imageCursor.moveToFirst();
            int columnIndex = imageCursor.getColumnIndex(filePathColumn[0]);
            picturePath = imageCursor.getString(columnIndex);
            if (picturePath == null) {
                picturePath = selectedImageUri.getPath();
                String wholeID = DocumentsContract
                        .getDocumentId(selectedImage);

                // Split at colon, use second item in the array
                String id = wholeID.split(":")[1];

                String[] column = { MediaStore.Images.Media.DATA };

                // where id is equal to
                String sel = MediaStore.Images.Media._ID + "=?";

                Cursor cursor = mainActivity.getContentResolver().query(
                        MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
                        column, sel, new String[] { id }, null);

                columnIndex = cursor.getColumnIndex(column[0]);

                if (cursor.moveToFirst()) {
                    picturePath = cursor.getString(columnIndex);
                }

                cursor.close();
            }
            picturePathAbs = new File(picturePath).getAbsolutePath();
            imageCursor.close();
        }

}

package com.ImageConvertingDemo;

import java.io.BufferedInputStream;
import java.io.FileInputStream;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.util.Log;
import android.widget.EditText;
import android.widget.ImageView;

public class MyActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        EditText tv = (EditText)findViewById(R.id.EditText01);
        ImageView iv = (ImageView)findViewById(R.id.ImageView01);
        FileInputStream in;
        BufferedInputStream buf;
            try 
            {
                in = new FileInputStream("/sdcard/smooth.png");
                buf = new BufferedInputStream(in,1070);
                System.out.println("1.................."+buf);
                byte[] bMapArray= new byte[buf.available()];
                tv.setText(bMapArray.toString());
                buf.read(bMapArray);
                Bitmap bMap = BitmapFactory.decodeByteArray(bMapArray, 0, bMapArray.length);

                /*for (int i = 0; i < bMapArray.length; i++) 
                {
                System.out.print("bytearray"+bMapArray[i]);
                }*/
                iv.setImageBitmap(bMap);
                //tv.setText(bMapArray.toString());
                //tv.setText(buf.toString());
                if (in != null) 
                {
                    in.close();
                }
                if (buf != null) 
                {
                    buf.close();
                }

            } 
            catch (Exception e) 
            {
                Log.e("Error reading file", e.toString());
            }
    }
}

public class BrowsePictureActivity extends Activity {

    // this is the action code we use in our intent, 
    // this way we know we're looking at the response from our own action
    private static final int SELECT_PICTURE = 1;

    private String selectedImagePath;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        ((Button) findViewById(R.id.Button01))
                .setOnClickListener(new OnClickListener() {

                    public void onClick(View arg0) {

                        // in onCreate or any event where your want the user to
                        // select a file
                        Intent intent = new Intent();
                        intent.setType("image/*");
                        intent.setAction(Intent.ACTION_GET_CONTENT);
                        startActivityForResult(Intent.createChooser(intent,
                                "Select Picture"), SELECT_PICTURE);
                    }
                });
    }

    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (resultCode == RESULT_OK) {
            if (requestCode == SELECT_PICTURE) {
                Uri selectedImageUri = data.getData();
                selectedImagePath = getPath(selectedImageUri);
            }
        }
    }

    /**
     * helper to retrieve the path of an image URI
     */
    public String getPath(Uri uri) {
            // just some safety built in 
            if( uri == null ) {
                // TODO perform some logging or show user feedback
                return null;
            }
            // try to retrieve the image from the media store first
            // this will only work for images selected from gallery
            String[] projection = { MediaStore.Images.Media.DATA };
            Cursor cursor = managedQuery(uri, projection, null, null, null);
            if( cursor != null ){
                int column_index = cursor
                .getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
                cursor.moveToFirst();
                return cursor.getString(column_index);
            }
            // this is our fallback here
            return uri.getPath();
    }

}

我通过@hcpl和@mad的解决方案。hcpl的解决方案很好地支持图库中的本地图像& mad在此基础上提供了一个更好的解决方案-它也有助于加载OI/Astro/Dropbox图像。但在我的应用程序中，虽然在picasa库工作，现在集成在Android画廊，这两个解决方案都失败了。

我进行了一些搜索和分析，最终得出了一个更好和优雅的解决方案，克服了这一限制。感谢Dimitar Darazhanski的博客，在这种情况下，他帮助了我，我修改了一些，使它更容易理解。这是我的解

public class BrowsePicture extends Activity {

//YOU CAN EDIT THIS TO WHATEVER YOU WANT
private static final int SELECT_PICTURE = 1;

private String selectedImagePath;
//ADDED
private String filemanagerstring;

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    ((Button) findViewById(R.id.Button01))
    .setOnClickListener(new OnClickListener() {

        public void onClick(View arg0) {

            // in onCreate or any event where your want the user to
            // select a file
            Intent intent = new Intent();
            intent.setType("image/*");
            intent.setAction(Intent.ACTION_GET_CONTENT);
            startActivityForResult(Intent.createChooser(intent,
                    "Select Picture"), SELECT_PICTURE);
        }
    });
}

public void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (resultCode == RESULT_OK) {
        if (requestCode == SELECT_PICTURE) {
            Uri selectedImageUri = data.getData();
            Log.d("URI VAL", "selectedImageUri = " + selectedImageUri.toString());
            selectedImagePath = getPath(selectedImageUri);

            if(selectedImagePath!=null){         
                // IF LOCAL IMAGE, NO MATTER IF ITS DIRECTLY FROM GALLERY (EXCEPT PICASSA ALBUM),
                // OR OI/ASTRO FILE MANAGER. EVEN DROPBOX IS SUPPORTED BY THIS BECAUSE DROPBOX DOWNLOAD THE IMAGE 
                // IN THIS FORM - file:///storage/emulated/0/Android/data/com.dropbox.android/...
                System.out.println("local image"); 
            }
            else{
                System.out.println("picasa image!");
                loadPicasaImageFromGallery(selectedImageUri);
            }
        }
    }
}


// NEW METHOD FOR PICASA IMAGE LOAD
private void loadPicasaImageFromGallery(final Uri uri) {
    String[] projection = {  MediaColumns.DATA, MediaColumns.DISPLAY_NAME };
    Cursor cursor = getContentResolver().query(uri, projection, null, null, null);
    if(cursor != null) {
        cursor.moveToFirst();

        int columnIndex = cursor.getColumnIndex(MediaColumns.DISPLAY_NAME);
        if (columnIndex != -1) {
            new Thread(new Runnable() {
                // NEW THREAD BECAUSE NETWORK REQUEST WILL BE MADE THAT WILL BE A LONG PROCESS & BLOCK UI
                // IF CALLED IN UI THREAD 
                public void run() {
                    try {
                        Bitmap bitmap = android.provider.MediaStore.Images.Media.getBitmap(getContentResolver(), uri);
                        // THIS IS THE BITMAP IMAGE WE ARE LOOKING FOR.
                    } catch (Exception ex) {
                        ex.printStackTrace();
                    }
                }
            }).start();
        }
    }
    cursor.close();
}


public String getPath(Uri uri) {
    String[] projection = {  MediaColumns.DATA};
    Cursor cursor = getContentResolver().query(uri, projection, null, null, null);
    if(cursor != null) {
        //HERE YOU WILL GET A NULLPOINTER IF CURSOR IS NULL
        //THIS CAN BE, IF YOU USED OI FILE MANAGER FOR PICKING THE MEDIA
        cursor.moveToFirst();
        int columnIndex = cursor.getColumnIndexOrThrow(MediaColumns.DATA);
        String filePath = cursor.getString(columnIndex);
        cursor.close();
        return filePath;
    }
    else 
        return uri.getPath();               // FOR OI/ASTRO/Dropbox etc
}

检查一下，如果有什么问题请告诉我。我已经测试过了，它在每种情况下都很好。

希望这对大家有所帮助。

万一有用的话;我这样做是为了得到位图:

InputStream is = context.getContentResolver().openInputStream(imageUri);
Bitmap bitmap = BitmapFactory.decodeStream(is);