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
hcpl的方法在kitkat之前工作得很好，但不能与DocumentsProvider API一起工作。为此，只需简单地遵循官方的Android文档提供者教程:https://developer.android.com/guide/topics/providers/document-provider.html ->打开一个文档，位图部分。
简单地，我使用了hcpl的代码并扩展了它:如果图像的检索路径的文件抛出异常，我调用这个函数:
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。
其他回答
在上面代码的基础上，我反映了如下代码，可能它更适合:
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;
}
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。
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());
}
}
}
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;
}
hcpl的方法在kitkat之前工作得很好，但不能与DocumentsProvider API一起工作。为此，只需简单地遵循官方的Android文档提供者教程:https://developer.android.com/guide/topics/providers/document-provider.html ->打开一个文档，位图部分。
简单地，我使用了hcpl的代码并扩展了它:如果图像的检索路径的文件抛出异常，我调用这个函数:
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。
推荐文章
- 警告:API ' variable . getjavacompile()'已过时，已被' variable . getjavacompileprovider()'取代
- 安装APK时出现错误
- 碎片中的onCreateOptionsMenu
- TextView粗体通过XML文件?
- 如何使线性布局的孩子之间的空间?
- DSL元素android.dataBinding。enabled'已过时，已被'android.buildFeatures.dataBinding'取代
- ConstraintLayout:以编程方式更改约束
- PANIC: AVD系统路径损坏。检查ANDROID_SDK_ROOT值
- 如何生成字符串类型的buildConfigField
- Recyclerview不调用onCreateViewHolder
- Android API 21工具栏填充
- Android L中不支持操作栏导航模式
- 如何在TextView中添加一个子弹符号?
- PreferenceManager getDefaultSharedPreferences在Android Q中已弃用
- 在Android Studio中创建aar文件
