我试图从我的应用程序中打开画廊内置应用程序中的图像/图片。
我有一个图片的URI(图片位于SD卡上)。
你有什么建议吗?
我试图从我的应用程序中打开画廊内置应用程序中的图像/图片。
我有一个图片的URI(图片位于SD卡上)。
你有什么建议吗?
当前回答
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();
}
}
}
}
}
其他回答
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。
以下是hcpl发布的优良代码的更新。但这适用于OI文件管理器,astro文件管理器和媒体库(测试)。所以我想它将适用于每个文件管理器(除了上面提到的这些,还有很多其他的吗?)修改了他写的代码。
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;
}
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();
}
}
这是我的例子,可能不完全是你的情况。
假设你从你的API提供者获得base64格式,给它一个文件名和文件扩展名,将它保存到文件系统中的某个位置。
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);}
不要忘记在AndroidManifest.xml中首先设置一个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XML在…/res/ XML /file_path.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,首先准备好文件提供程序,将已知且可访问的图片源的Uri传递给Intent,否则,将图片保存在所需的位置,然后将位置(作为Uri)传递给Intent。
这是我对这个主题的回顾,收集了这里的所有信息,再加上其他相关的堆栈溢出问题。它从某些提供者返回图像,同时处理内存不足的情况和图像旋转。它支持画廊,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;
}
}
引用:
http://developer.android.com/training/displaying-bitmaps/index.html 通过编程方式从Android内置的Gallery应用程序中获取/选择一张图像 在将图像加载到位图对象时出现奇怪的内存不足问题 使用ExifInterface设置图像方向 https://gist.github.com/9re/1990019 如何获得位图信息,然后解码位图从internet-inputStream?