更新

Question

我正在尝试从应用程序内部的Gallery内置应用程序中打开图像/图片。

我有图片的URI（图片位于SD卡上）。

你有什么建议吗？

Answer 1

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

更新

我刚刚回顾了我的原始答案并创建了一个简单的Android Studio项目，您可以从github签出并直接在您的系统上导入。

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

（请注意，多文件选择仍需要工作）

单张图片选择

由于用户疯狂，支持文件浏览器中的图像。

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();
    }

}

选择多张照片

由于有人在评论中要求提供信息，因此最好收集信息。

在意图上设置额外参数EXTRA_ALLOW_MULTIPLE：

intent.putExtra(Intent.EXTRA_ALLOW_MULTIPLE, true);

在该参数的结果处理检查中：

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
       }
   }
}

请注意，这仅受API级别18 +。

支持

Answer 2

这是hcpl发布的精细代码的更新。但这适用于OI文件管理器，astro文件管理器和媒体库（已测试）。所以我想它会适用于每个文件管理器（除了提到的那些之外还有很多其他文件管理器吗？）。对他写的代码做了一些修改。

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);
            }
        });
    }

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

                //OI FILE Manager
                filemanagerstring = selectedImageUri.getPath();

                //MEDIA GALLERY
                selectedImagePath = getPath(selectedImageUri);

                //DEBUG PURPOSE - you can delete this if you want
                if(selectedImagePath!=null)
                    System.out.println(selectedImagePath);
                else System.out.println("selectedImagePath is null");
                if(filemanagerstring!=null)
                    System.out.println(filemanagerstring);
                else System.out.println("filemanagerstring is null");

                //NOW WE HAVE OUR WANTED STRING
                if(selectedImagePath!=null)
                    System.out.println("selectedImagePath is the right one for you!");
                else
                    System.out.println("filemanagerstring is the right one for you!");
            }
        }
    }

    //UPDATED!
    public String getPath(Uri uri) {
        String[] projection = { MediaStore.Images.Media.DATA };
        Cursor cursor = managedQuery(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
            int column_index = cursor
            .getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
            cursor.moveToFirst();
            return cursor.getString(column_index);
        }
        else return null;
    }

Answer 3

hcpl的方法完全可以在KitKat之前完成，但不能使用DocumentsProvider API。为此，只需按照文档提供者的官方Android教程进行操作：https://developer.android.com/guide/topics/providers/document-provider.html - ＆gt;打开文档，位图部分。

我只是使用了hcpl的代码并对其进行了扩展：如果带有检索到的图像路径的文件抛出异常，我会调用此函数：

private Bitmap getBitmapFromUri(Uri uri) throws IOException {
        ParcelFileDescriptor parcelFileDescriptor =
             getContentResolver().openFileDescriptor(uri, "r");
        FileDescriptor fileDescriptor = parcelFileDescriptor.getFileDescriptor();
        Bitmap image = BitmapFactory.decodeFileDescriptor(fileDescriptor);
        parcelFileDescriptor.close();
        return image;
}

在Nexus 5上测试。

Answer 4

基于上面的代码，我反映了下面的代码，可能更适合：

public String getPath(Uri uri) {
    String selectedImagePath;
    //1:MEDIA GALLERY --- query from MediaStore.Images.Media.DATA
    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();
        selectedImagePath = cursor.getString(column_index);
    }else{
        selectedImagePath = null;
    }

    if(selectedImagePath == null){
        //2:OI FILE Manager --- call method: uri.getPath()
        selectedImagePath = uri.getPath();
    }
    return selectedImagePath;
}

Answer 5

我从@hcpl＆amp;中找到了解决方案。 @狂。 hcpl的解决方案很好地支持了画廊中的本地图像。疯狂提供了一个更好的解决方案 - 它也有助于加载OI / Astro / Dropbox图像。但是在我的应用程序中，在处理现在集成在Android Gallery中的 picasa库时，两种解决方案都失败了。

我搜索过＆amp;分析了一下＆amp;最终会有一个更好的＆amp;优雅的解决方案克服了这一局限。感谢Dimitar Darazhanski他的博客，在这种情况下帮助了我，我修改了一下以便更容易理解。这是我的解决方案 -

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＆amp;如果有问题，请告诉我。我测试了它＆amp;它适用于所有情况。

希望这会对每个人有所帮助。

Answer 6

假设您的SD卡目录中有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，您可以决定要对活动中的内容做什么。

这是一个检索图像路径名的示例，使用您的代码对其进行测试，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();
     }
   }

我的建议是尝试检索图像正常工作，我认为问题是访问SD卡上图像的内容。看看Displaying images on sd card。

如果您可以通过提供正确提供程序的示例来启动并运行，那么您应该能够找到适合您代码的解决方法。

根据您的进度更新此问题，让我更新。祝你好运

Answer 7

这是我对这个主题的重新审视，收集了这里的所有信息，以及其他相关的堆栈溢出问题。它返回来自某个提供程序的图像，同时处理内存不足的情况和图像旋转。它支持图库，picasa和文件管理器，如下拉框。用法很简单：作为输入，构造函数接收内容解析器和uri。输出是最终的位图。

/**
 * Creates resized images without exploding memory. Uses the method described in android
 * documentation concerning bitmap allocation, which is to subsample the image to a smaller size,
 * close to some expected size. This is required because the android standard library is unable to
 * create a reduced size image from an image file using memory comparable to the final size (and
 * loading a full sized multi-megapixel picture for processing may exceed application memory budget).
 */

public class UserPicture {
    static int MAX_WIDTH = 600;
    static int MAX_HEIGHT = 800;
    Uri uri;
    ContentResolver resolver;
    String path;
    Matrix orientation;
    int storedHeight;
    int storedWidth;

    public UserPicture(Uri uri, ContentResolver resolver) {
        this.uri = uri;
        this.resolver = resolver;
    }

    private boolean getInformation() throws IOException {
        if (getInformationFromMediaDatabase())
            return true;

        if (getInformationFromFileSystem())
            return true;

        return false;
    }

    /* Support for gallery apps and remote ("picasa") images */
    private boolean getInformationFromMediaDatabase() {
        String[] fields = { Media.DATA, ImageColumns.ORIENTATION };
        Cursor cursor = resolver.query(uri, fields, null, null, null);

        if (cursor == null)
            return false;

        cursor.moveToFirst();
        path = cursor.getString(cursor.getColumnIndex(Media.DATA));
        int orientation = cursor.getInt(cursor.getColumnIndex(ImageColumns.ORIENTATION));
        this.orientation = new Matrix();
        this.orientation.setRotate(orientation);
        cursor.close();

        return true;
    }

    /* Support for file managers and dropbox */
    private boolean getInformationFromFileSystem() throws IOException {
        path = uri.getPath();

        if (path == null)
            return false;

        ExifInterface exif = new ExifInterface(path);
        int orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION,
                                               ExifInterface.ORIENTATION_NORMAL);

        this.orientation = new Matrix();
        switch(orientation) {
            case ExifInterface.ORIENTATION_NORMAL:
                /* Identity matrix */
                break;
            case ExifInterface.ORIENTATION_FLIP_HORIZONTAL:
                this.orientation.setScale(-1, 1);
                break;
            case ExifInterface.ORIENTATION_ROTATE_180:
                this.orientation.setRotate(180);
                break;
            case ExifInterface.ORIENTATION_FLIP_VERTICAL:
                this.orientation.setScale(1, -1);
                break;
            case ExifInterface.ORIENTATION_TRANSPOSE:
                this.orientation.setRotate(90);
                this.orientation.postScale(-1, 1);
                break;
            case ExifInterface.ORIENTATION_ROTATE_90:
                this.orientation.setRotate(90);
                break;
            case ExifInterface.ORIENTATION_TRANSVERSE:
                this.orientation.setRotate(-90);
                this.orientation.postScale(-1, 1);
                break;
            case ExifInterface.ORIENTATION_ROTATE_270:
                this.orientation.setRotate(-90);
                break;
        }

        return true;
    }

    private boolean getStoredDimensions() throws IOException {
        InputStream input = resolver.openInputStream(uri);
        Options options = new Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeStream(resolver.openInputStream(uri), null, options);

        /* The input stream could be reset instead of closed and reopened if it were possible
           to reliably wrap the input stream on a buffered stream, but it's not possible because
           decodeStream() places an upper read limit of 1024 bytes for a reset to be made (it calls
           mark(1024) on the stream). */
        input.close();

        if (options.outHeight <= 0 || options.outWidth <= 0)
            return false;

        storedHeight = options.outHeight;
        storedWidth = options.outWidth;

        return true;
    }

    public Bitmap getBitmap() throws IOException {
        if (!getInformation())
            throw new FileNotFoundException();

        if (!getStoredDimensions())
            throw new InvalidObjectException(null);

        RectF rect = new RectF(0, 0, storedWidth, storedHeight);
        orientation.mapRect(rect);
        int width = (int)rect.width();
        int height = (int)rect.height();
        int subSample = 1;

        while (width > MAX_WIDTH || height > MAX_HEIGHT) {
            width /= 2;
            height /= 2;
            subSample *= 2;
        }

        if (width == 0 || height == 0)
            throw new InvalidObjectException(null);

        Options options = new Options();
        options.inSampleSize = subSample;
        Bitmap subSampled = BitmapFactory.decodeStream(resolver.openInputStream(uri), null, options);

        Bitmap picture;
        if (!orientation.isIdentity()) {
            picture = Bitmap.createBitmap(subSampled, 0, 0, options.outWidth, options.outHeight,
                                          orientation, false);
            subSampled.recycle();
        } else
            picture = subSampled;

        return picture;
    }
}

参考文献：

Answer 8

有两个关于图像选择器的有用教程，其中包含可下载的源代码：

How to Create Android Image Picker

How to Select and Crop Image on Android

但是，应用程序将被强制关闭某些时候，您可以通过将android：configChanges属性添加到Manifest文件中的主要活动来修复它，如：

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

似乎相机API失去了控制方向，所以这将有所帮助。：）

Answer 9

要显示图片和视频，请尝试以下操作：

    Intent intent = new Intent();
    intent = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
    startActivityForResult(intent, 1);
    startActivityForResult(Intent.createChooser(intent,"Wybierz plik"), SELECT_FILE);

Answer 10

以防它有帮助;我这样做是为了得到位图：

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

Answer 11

以上答案是正确的。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了。我为图像路径获取空值。我使用以下解决方案进行了修复和优化。在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();
        }

}

Answer 12

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();
    }

}

Answer 13

检索特定类型的文件

此示例将获取图像的副本。

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，您请求打开由其他应用管理的文件

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
        ...
    }
}

Original source

Answer 14

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());
            }
    }
}

Answer 15

除了之前的答案之外，如果您在找到正确的路径时遇到问题（如AndroZip），您可以使用：

  public String getPath(Uri uri ,ContentResolver contentResolver) {
        String[] projection = {  MediaStore.MediaColumns.DATA};
        Cursor cursor;
        try{
            cursor = contentResolver.query(uri, projection, null, null, null);
        } catch (SecurityException e){
            String path = uri.getPath();
            String result = tryToGetStoragePath(path);
            return  result;
        }
        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(MediaStore.MediaColumns.DATA);
            String filePath = cursor.getString(columnIndex);
            cursor.close();
            return filePath;
        }
        else
            return uri.getPath();               // FOR OI/ASTRO/Dropbox etc
    }

    private String tryToGetStoragePath(String path) {
        int actualPathStart = path.indexOf("//storage");
        String result = path;

        if(actualPathStart!= -1 && actualPathStart< path.length())
            result = path.substring(actualPathStart+1 , path.length());

        return result;
    }

Answer 16

请查看从图库中选择单张图片的答案

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();
                }
            }
        }
    }
}

Answer 17

从图库或相机中打开图片的最快方式。

原始参考： get image from gallery in android programmatically

以下方法将从图库或相机接收图像，并将在ImageView中显示。所选图像将在内部存储。

xml的代码

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="com.exampledemo.parsaniahardik.uploadgalleryimage.MainActivity">

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/btn"
        android:layout_gravity="center_horizontal"
        android:layout_marginTop="20dp"
        android:textAppearance="?android:attr/textAppearanceLarge"
        android:text="Capture Image and upload to server" />

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Below image is fetched from server"
        android:layout_marginTop="5dp"
        android:textSize="23sp"
        android:gravity="center"
        android:textColor="#000"/>

    <ImageView
        android:layout_width="300dp"
        android:layout_height="300dp"
        android:layout_gravity="center"
        android:layout_marginTop="10dp"
        android:scaleType="fitXY"
        android:src="@mipmap/ic_launcher"
        android:id="@+id/iv"/>

</LinearLayout>

JAVA课程

import android.content.Intent;
import android.graphics.Bitmap;
import android.media.MediaScannerConnection;
import android.os.Environment;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;
import com.androidquery.AQuery;
import org.json.JSONException;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Calendar;
import java.util.HashMap;

public class MainActivity extends AppCompatActivity implements AsyncTaskCompleteListener{

    private ParseContent parseContent;
    private Button btn;
    private ImageView imageview;
    private static final String IMAGE_DIRECTORY = "/demonuts_upload_camera";
    private final int CAMERA = 1;
    private AQuery aQuery;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        parseContent = new ParseContent(this);
        aQuery = new AQuery(this);

        btn = (Button) findViewById(R.id.btn);
        imageview = (ImageView) findViewById(R.id.iv);

        btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
                startActivityForResult(intent, CAMERA);
            }
        });

    }

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {

        super.onActivityResult(requestCode, resultCode, data);
        if (resultCode == this.RESULT_CANCELED) {
            return;
        }
        if (requestCode == CAMERA) {
            Bitmap thumbnail = (Bitmap) data.getExtras().get("data");
            String path = saveImage(thumbnail);
            try {
                uploadImageToServer(path);
            } catch (IOException e) {
                e.printStackTrace();
            } catch (JSONException e) {
                e.printStackTrace();
            }
        }
    }

    private void uploadImageToServer(final String path) throws IOException, JSONException {

        if (!AndyUtils.isNetworkAvailable(MainActivity.this)) {
            Toast.makeText(MainActivity.this, "Internet is required!", Toast.LENGTH_SHORT).show();
            return;
        }

        HashMap<String, String> map = new HashMap<String, String>();
        map.put("url", "https://demonuts.com/Demonuts/JsonTest/Tennis/uploadfile.php");
        map.put("filename", path);
        new MultiPartRequester(this, map, CAMERA, this);
        AndyUtils.showSimpleProgressDialog(this);
    }

    @Override
    public void onTaskCompleted(String response, int serviceCode) {
        AndyUtils.removeSimpleProgressDialog();
        Log.d("res", response.toString());
        switch (serviceCode) {

            case CAMERA:
                if (parseContent.isSuccess(response)) {
                    String url = parseContent.getURL(response);
                    aQuery.id(imageview).image(url);
                }
        }
    }

    public String saveImage(Bitmap myBitmap) {
        ByteArrayOutputStream bytes = new ByteArrayOutputStream();
        myBitmap.compress(Bitmap.CompressFormat.JPEG, 90, bytes);
        File wallpaperDirectory = new File(
                Environment.getExternalStorageDirectory() + IMAGE_DIRECTORY);
        // have the object build the directory structure, if needed.
        if (!wallpaperDirectory.exists()) {
            wallpaperDirectory.mkdirs();
        }

        try {
            File f = new File(wallpaperDirectory, Calendar.getInstance()
                    .getTimeInMillis() + ".jpg");
            f.createNewFile();
            FileOutputStream fo = new FileOutputStream(f);
            fo.write(bytes.toByteArray());
            MediaScannerConnection.scanFile(this,
                    new String[]{f.getPath()},
                    new String[]{"image/jpeg"}, null);
            fo.close();
            Log.d("TAG", "File Saved::--->" + f.getAbsolutePath());

            return f.getAbsolutePath();
        } catch (IOException e1) {
            e1.printStackTrace();
        }
        return "";
    }
}

Answer 18

这是我的示例，可能与您的情况不完全相同。

假设您从API提供程序获取base64格式，为其提供文件名和文件扩展名，然后将其保存到文件系统中的特定位置。

public static void shownInBuiltInGallery(final Context ctx, String strBase64Image, final String strFileName, final String strFileExtension){

new AsyncTask<String, String, File>() {
    @Override
    protected File doInBackground(String... strBase64Image) {

        Bitmap bmpImage = convertBase64StringToBitmap(strBase64Image[0], Base64.NO_WRAP);

        if(bmpImage == null) {
            cancel(true);
            return null;
        }

        byte[] byImage = null;

        if(strFileExtension.compareToIgnoreCase(FILE_EXTENSION_JPG) == 0) {
            byImage = convertToJpgByte(bmpImage); // convert bitmap to binary for latter use
        } else if(strFileExtension.compareToIgnoreCase(FILE_EXTENSION_PNG) == 0){
            byImage = convertToPngByte(bmpImage); // convert bitmap to binary for latter use
        } else if(strFileExtension.compareToIgnoreCase(FILE_EXTENSION_BMP) == 0){
            byImage = convertToBmpByte(bmpImage); // convert bitmap to binary for latter use
        } else {
            cancel(true);
            return null;
        }

        if(byImage == null) {
            cancel(true);
            return null;
        }

        File imageFolder = ctx.getExternalCacheDir();

        if(imageFolder.exists() == false){
            if(imageFolder.mkdirs() == false){
                cancel(true);
                return null;
            }
        }

        File imageFile = null;

        try {
            imageFile = File.createTempFile(strFileName, strFileExtension, imageFolder);
        } catch (IOException e){
            e.printStackTrace();
        }

        if(imageFile == null){
            cancel(true);
            return null;
        }

        if (imageFile.exists() == true) {
            if(imageFile.delete() == false){
                cancel(true);
                return null;
            }
        }

        FileOutputStream fos = null;

        try {
            fos = new FileOutputStream(imageFile.getPath());
            fos.write(byImage);
            fos.flush();
            fos.close();
        } catch (java.io.IOException e) {
            e.printStackTrace();
        } finally {
            fos = null;
        }

        return imageFile;
    }

    @Override
    protected void onPostExecute(File file) {
        super.onPostExecute(file);

            String strAuthority = ctx.getPackageName() + ".provider";
            Uri uriImage = FileProvider.getUriForFile(ctx, strAuthority, file);

            Intent intent = new Intent(Intent.ACTION_VIEW);
            intent.setDataAndType(uriImage, "image/*");
            intent.setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
            ctx.startActivity(intent);

    }
}.execute(strBase64Image);}

别忘了首先在AndroidManifest.xml中设置适当的文件提供程序

        <provider
        android:name="android.support.v4.content.FileProvider"
        android:authorities="${applicationId}.provider"
        android:exported="false"
        android:grantUriPermissions="true">

        <meta-data
            android:name="android.support.FILE_PROVIDER_PATHS"
            android:resource="@xml/file_paths"/>
    </provider>

文件路径是... / res / xml / file_path.xml中的xml

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

<external-files-path name="external_files" path="Accessory"/>

<external-path name="ex_Download" path="Download/" />
<external-path name="ex_Pictures" path="Pictures/" />

<external-files-path name="my_Download" path="Download/" />
<external-files-path name="my_Pictures" path="Pictures/" />
<external-cache-path name="my_cache" path="." />

<files-path name="private_Download" path="Download/" />
<files-path name="private_Pictures" path="Pictures/" />
<cache-path name="private_cache" path="." />

长话短说，首先要准备好文件提供者，然后将Uri传递给Intent以获取已知的可访问图片来源，否则，将图片保存在所需的位置，然后将该位置（以Uri形式）传递给Intent。

以编程方式从Android的内置Gallery应用程序中获取/选择图像

18 个答案:

更新

单张图片选择

选择多张照片

检索特定类型的文件

打开特定类型的文件