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);

假设在SD卡目录中有一个图像文件夹仅用于图像。

Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
// tells your intent to get the contents
// opens the URI for your image directory on your sdcard
intent.setType("file:///sdcard/image/*"); 
startActivityForResult(intent, 1);

然后，您可以决定如何处理活动中的内容。

这是一个检索图像路径名称的示例，用您的代码进行测试，以确保您可以处理返回的结果。您可以根据需要更改代码以更好地满足您的需求。

protected final void onActivityResult(final int requestCode, final int
                     resultCode, final Intent i) {
    super.onActivityResult(requestCode, resultCode, i);

  // this matches the request code in the above call
  if (requestCode == 1) {
      Uri _uri = i.getData();

    // this will be null if no image was selected...
    if (_uri != null) {
      // now we get the path to the image file
     cursor = getContentResolver().query(_uri, null,
                                      null, null, null);
     cursor.moveToFirst();
     String imageFilePath = cursor.getString(0);
     cursor.close();
     }
   }

我的建议是尽量让检索图像工作正确，我认为问题是在存储卡上访问图像的内容。看一下在sd卡上显示图像。

如果您能够启动并运行它(可能通过示例提供正确的提供程序)，那么您应该能够为您的代码找到一种变通方法。

通过更新这个问题来让我了解你的进展。祝你好运

这是一个完整的解决方案。我刚刚用@mad在下面的答案中提供的信息更新了这个示例代码。还可以查看下面来自@Khobaib的解决方案，解释如何处理picasa图像。

更新

我刚刚回顾了我最初的答案，并创建了一个简单的Android Studio项目，您可以从github签出并直接导入到您的系统。

https://github.com/hanscappelle/SO-2169649

(注意多个文件选择仍然需要工作)

单张图片选择

感谢用户mad，支持来自文件探索者的图像。

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);

        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();
                String path = cursor.getString(column_index);
                cursor.close();
                return path;
            }
            // this is our fallback here
            return uri.getPath();
    }

}

选择多张图片

因为有人在评论中要求这些信息，所以最好收集信息。

在intent上设置一个额外的参数EXTRA_ALLOW_MULTIPLE:

intent.putExtra(Intent.EXTRA_ALLOW_MULTIPLE, true);

在Result处理中检查该参数:

if (Intent.ACTION_SEND_MULTIPLE.equals(data.getAction()))
        && Intent.hasExtra(Intent.EXTRA_STREAM)) {
    // retrieve a collection of selected images
    ArrayList<Parcelable> list = intent.getParcelableArrayListExtra(Intent.EXTRA_STREAM);
    // iterate over these images
    if( list != null ) {
       for (Parcelable parcel : list) {
         Uri uri = (Uri) parcel;
         // TODO handle the images one by one here
       }
   }
} 

注意，只有API级别18+支持这一点。

请找到从图库中选择单个图像的答案

import android.app.Activity;
import android.net.Uri;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;

import java.io.ByteArrayOutputStream;
import java.io.FileNotFoundException;
import java.io.InputStream;

public class PickImage extends Activity {

    Button btnOpen, btnGet, btnPick;
    TextView textInfo1, textInfo2;
    ImageView imageView;

    private static final int RQS_OPEN_IMAGE = 1;
    private static final int RQS_GET_IMAGE = 2;
    private static final int RQS_PICK_IMAGE = 3;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.image_pick);
        btnOpen = (Button)findViewById(R.id.open);
        btnGet = (Button)findViewById(R.id.get);
        btnPick = (Button)findViewById(R.id.pick);
        textInfo1 = (TextView)findViewById(R.id.info1);
        textInfo2 = (TextView)findViewById(R.id.info2);
        imageView = (ImageView) findViewById(R.id.image);

        btnOpen.setOnClickListener(btnOpenOnClickListener);
        btnGet.setOnClickListener(btnGetOnClickListener);
        btnPick.setOnClickListener(btnPickOnClickListener);
    }

    View.OnClickListener btnOpenOnClickListener = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent intent = new Intent();
            intent.setAction(Intent.ACTION_OPEN_DOCUMENT);
            intent.addCategory(Intent.CATEGORY_OPENABLE);
            intent.setType("image/*");

            startActivityForResult(intent, RQS_OPEN_IMAGE);
        }
    };

    View.OnClickListener btnGetOnClickListener = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent intent = new Intent();
            intent.setAction(Intent.ACTION_GET_CONTENT);
            intent.addCategory(Intent.CATEGORY_OPENABLE);
            intent.setType("image/*");

            startActivityForResult(intent, RQS_OPEN_IMAGE);
        }
    };

    View.OnClickListener btnPickOnClickListener = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent intent = new Intent(Intent.ACTION_PICK,
                    android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
            startActivityForResult(intent, RQS_PICK_IMAGE);
        }
    };

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (resultCode == Activity.RESULT_OK) {


            if (requestCode == RQS_OPEN_IMAGE ||
                    requestCode == RQS_GET_IMAGE ||
                    requestCode == RQS_PICK_IMAGE) {

                imageView.setImageBitmap(null);
                textInfo1.setText("");
                textInfo2.setText("");

                Uri mediaUri = data.getData();
                textInfo1.setText(mediaUri.toString());
                String mediaPath = mediaUri.getPath();
                textInfo2.setText(mediaPath);

                //display the image
                try {
                    InputStream inputStream = getBaseContext().getContentResolver().openInputStream(mediaUri);
                    Bitmap bm = BitmapFactory.decodeStream(inputStream);

                   ByteArrayOutputStream stream = new ByteArrayOutputStream();
                    byte[] byteArray = stream.toByteArray();

                    imageView.setImageBitmap(bm);

                } catch (FileNotFoundException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

检索特定类型的文件

这个示例将获得图像的副本。

static final int REQUEST_IMAGE_GET = 1;

public void selectImage() {
    Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
    intent.setType("image/*");
    if (intent.resolveActivity(getPackageManager()) != null) {
        startActivityForResult(intent, REQUEST_IMAGE_GET);
    }
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == REQUEST_IMAGE_GET && resultCode == RESULT_OK) {
        Bitmap thumbnail = data.getParcelable("data");
        Uri fullPhotoUri = data.getData();
        // Do work with photo saved at fullPhotoUri
        ...
    }
}

打开特定类型的文件

在4.4或更高版本上运行时，您请求打开由另一个应用程序管理的文件

static final int REQUEST_IMAGE_OPEN = 1;

public void selectImage() {
    Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
    intent.setType("image/*");
    intent.addCategory(Intent.CATEGORY_OPENABLE);
    // Only the system receives the ACTION_OPEN_DOCUMENT, so no need to test.
    startActivityForResult(intent, REQUEST_IMAGE_OPEN);
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == REQUEST_IMAGE_OPEN && resultCode == RESULT_OK) {
        Uri fullPhotoUri = data.getData();
        // Do work with full size photo saved at fullPhotoUri
        ...
    }
}

原始来源

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。：）