Android 4.4以上拍照或者从图库选择图片,获取图片路径

Android 4.4以上拍照或者从图库选择图片,获取图片路径

一．图库选择图片，获取图片路径

最近在做一个从图库选择图片或拍照,然后裁剪的功能.本来是没问题的,一直在用

的

Intent intent=new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);

方式来做,是调用系统图库来做,但是发现如果有图片是同步到google相册的话,图库里面能看到一个auto backup的目录,点进去选图片的话是无法获取到图片的路径的.因为那些图片根本就不存在于手机上.然后看到无论是百度贴吧,Instagram,或者还有些会选取图片做修改的app,都是用一个很漂亮的图片选择器(4.4以上,4.3的还是用系统旧的图库).





而这个图片选择器可以屏蔽掉那个auto
backup的目录.所以就开始打算用这个图片选择器来选图片了.

这个方法就是

Intent intent=new Intent(Intent.ACTION_GET_CONTENT);//ACTION_OPEN_DOCUMENT
intent.addCategory(Intent.CATEGORY_OPENABLE);
intent.setType("image/jpeg");
if(android.os.Build.VERSION.SDK_INT>=android.os.Build.VERSION_CODES.KITKAT){
startActivityForResult(intent, SELECT_PIC_KITKAT);
}else{
startActivityForResult(intent, SELECT_PIC);
}

为什么要分开不同版本呢?其实在4.3或以下可以直接用ACTION_GET_CONTENT的,在4.4或以上,官方建议用ACTION_OPEN_DOCUMENT,但其实都不算太大区别,区别是他们返回的Uri,那个才叫大区别.这就是困扰了我一整天的问题所在了.

4.3或以下,选了图片之后,根据Uri来做处理,很多帖子都有了,我就不详细说了.主要是4.4,如果使用上面pick的原生方法来选图,返回的uri还是正常的,但如果用ACTION_GET_CONTENT的方法,返回的uri跟4.3是完全不一样的,4.3返回的是带文件路径的,而4.4返回的却是content://com.Android.providers.media.documents/document/image:3951这样的,没有路径,只有图片编号的uri.这就导致接下来无法根据图片路径来裁剪的步骤了.

还好找了很多方法,包括加权限啊什么的,中间还试过用一些方法,自己的app没崩溃,倒是让系统图库崩溃了,引发了Java.lang.SecurityException.

Caused by: java.lang.SecurityException: Permission Denial: opening provider com.android.providers.media.MediaDocumentsProvider from ProcessRecord{437b5d88 9494:com.google.android.gallery3d/u0a20} (pid=9494, uid=10020) requires android.permission.MANAGE_DOCUMENTS or android.permission.MANAGE_DOCUMENTS

看来4.4的系统还是有些bug.重点来了,4.4得到的uri,需要以下方法来获取文件的路径

import android.content.ContentUris;
import android.content.Context;
import android.database.Cursor;
import android.net.Uri;
import android.os.Build;
import android.os.Environment;
import android.provider.DocumentsContract;
import android.provider.MediaStore;
import android.util.Log;

/**
* Created by hanvon1 on 16-4-20.
*/
public class GalleryUtil {

private static String TAG = "GalleryUtil";

public static String getPath(final Context context, final Uri uri) {

final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;

// DocumentProvider
if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
// ExternalStorageProvider
if (isExternalStorageDocument(uri)) {
final String docId = DocumentsContract.getDocumentId(uri);
final String[] split = docId.split(":");
final String type = split[0];

if ("primary".equalsIgnoreCase(type)) {
Log.d(TAG, "getPath: is isExternalStorageDocument");
return Environment.getExternalStorageDirectory() + "/" + split[1];
}

// TODO handle non-primary volumes
}
// DownloadsProvider
else if (isDownloadsDocument(uri)) {

final String id = DocumentsContract.getDocumentId(uri);
final Uri contentUri = ContentUris.withAppendedId(
Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));

Log.d(TAG, "getPath: is isDownloadsDocument");
return getDataColumn(context, contentUri, null, null);
}
// MediaProvider
else if (isMediaDocument(uri)) {
final String docId = DocumentsContract.getDocumentId(uri);
final String[] split = docId.split(":");
final String type = split[0];

Uri contentUri = null;
if ("image".equals(type)) {
contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
} else if ("video".equals(type)) {
contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
} else if ("audio".equals(type)) {
contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
}

final String selection = "_id=?";
final String[] selectionArgs = new String[] {
split[1]
};

Log.d(TAG, "getPath: is isMediaDocument");
return getDataColumn(context, contentUri, selection, selectionArgs);
}
}
// MediaStore (and general)
else if ("content".equalsIgnoreCase(uri.getScheme())) {

// Return the remote address
if (isGooglePhotosUri(uri)) {
Log.d(TAG, "getPath: is isGooglePhotosUri");
return uri.getLastPathSegment();
}

Log.d(TAG, "getPath: is MediaStore");
return getDataColumn(context, uri, null, null);
}
// File
else if ("file".equalsIgnoreCase(uri.getScheme())) {
Log.d(TAG, "getPath: is File");
return uri.getPath();
}

return null;
}

/**
* Get the value of the data column for this Uri. This is useful for
* MediaStore Uris, and other file-based ContentProviders.
*
* @param context The context.
* @param uri The Uri to query.
* @param selection (Optional) Filter used in the query.
* @param selectionArgs (Optional) Selection arguments used in the query.
* @return The value of the _data column, which is typically a file path.
*/
public static String getDataColumn(Context context, Uri uri, String selection,
String[] selectionArgs) {

Cursor cursor = null;
final String column = "_data";
final String[] projection = {
column
};

try {
cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs,
null);
if (cursor != null && cursor.moveToFirst()) {
final int index = cursor.getColumnIndexOrThrow(column);
return cursor.getString(index);
}
} finally {
if (cursor != null)
cursor.close();
}
return null;
}

/**
* @param uri The Uri to check.
* @return Whether the Uri authority is ExternalStorageProvider.
*/
public static boolean isExternalStorageDocument(Uri uri) {
return "com.android.externalstorage.documents".equals(uri.getAuthority());
}

/**
* @param uri The Uri to check.
* @return Whether the Uri authority is DownloadsProvider.
*/
public static boolean isDownloadsDocument(Uri uri) {
return "com.android.providers.downloads.documents".equals(uri.getAuthority());
}

/**
* @param uri The Uri to check.
* @return Whether the Uri authority is MediaProvider.
*/
public static boolean isMediaDocument(Uri uri) {
return "com.android.providers.media.documents".equals(uri.getAuthority());
}

/**
* @param uri The Uri to check.
* @return Whether the Uri authority is Google Photos.
*/
public static boolean isGooglePhotosUri(Uri uri) {
return "com.google.android.apps.photos.content".equals(uri.getAuthority());
}
}

但是在三星手机上可能会出问题昨天发现了个bug,如果在4.4上面不用"图片"来选,用"图库"来选,就会无法读取到图片路径,所以只需要加个判断,如果是用旧方式来选,就用旧方式来读,就是如果

DocumentsContract.isDocumentUri(context, uri) 返回false的话,就用旧的方式

public static String selectImage(Context context,Intent data){
Uri selectedImage = data.getData();
//      Log.e(TAG, selectedImage.toString());
if(selectedImage!=null){
String uriStr=selectedImage.toString();
String path=uriStr.substring(10,uriStr.length());
if(path.startsWith("com.sec.android.gallery3d")){
Log.e(TAG, "It's auto backup pic path:"+selectedImage.toString());
return null;
}
}
String[] filePathColumn = { MediaStore.Images.Media.DATA };
Cursor cursor = context.getContentResolver().query(selectedImage,filePathColumn, null, null, null);
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
String picturePath = cursor.getString(columnIndex);
cursor.close();
return picturePath;
}

二．调用系统相机，获取图片

//实例化一个intent，并指定action
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
//指定一个图片路径对应的file对象
uri = Uri.fromFile(ImageUtil.getImageFile());
intent.putExtra(MediaStore.EXTRA_OUTPUT, uri);
//启动activity
startActivityForResult(intent, REQUEST_CODE_CAMERA);

但是在onActivityResult(int requestCode, int resultCode, Intent data)代码中得到的data总为null？

默认情况下，即不需要指定intent.putExtra(MediaStore.EXTRA_OUTPUT, uri);照相机有自己默认的存储路径，拍摄的照片将返回一个缩略图。如果想访问原始图片，可以通过dat extra能够得到原始图片位置。即，如果指定了目标uri，data就没有数据，如果没有指定uri，则data就返回有数据！现在想想，这种设计还是很合理的！

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode) {
case REQUEST_CODE_CAMERA:
if (resultCode == RESULT_OK) {
if(data !=null){ //可能尚未指定intent.putExtra(MediaStore.EXTRA_OUTPUT, uri);
//返回有缩略图
if(data.hasExtra("data")){
Bitmap thumbnail = data.getParcelableExtra("data");
//得到bitmap后的操作
}
}else{
//由于指定了目标uri，存储在目标uri，intent.putExtra(MediaStore.EXTRA_OUTPUT, uri);
// 通过目标uri，找到图片
// 对图片的缩放处理
// 操作
}
}
}
}