Android打开相机和相册的方法--很受用

1，打开相册的方法

Intent intent = new Intent(Intent.ACTION_PICK);
intent.setDataAndType(MediaStore.Images.Media.INTERNAL_CONTENT_URI, "image/*");
startActivityForResult(intent, 0);

2，打开相机的方法(涉及到7.0的权限，看另一篇博客)

mFilePath = Environment.getExternalStorageDirectory().getPath() + File.separator + System.currentTimeMillis() + ".png";// 照相后指定图片的地址，在回调中会用到

Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);// 启动系统相机
intent.putExtra(MediaStore.EXTRA_OUTPUT, getUriForFile(Issue_Activity.this, new File(mFilePath)));//相机直接给缓存地址
startActivityForResult(intent, 1001);

private static Uri getUriForFile(Context context, File file) {
if (context == null || file == null) {
throw new NullPointerException();
}
Uri uri;
if (Build.VERSION.SDK_INT >= 24) {//7.0权限(需要在修改xml文件)
uri = FileProvider.getUriForFile(context.getApplicationContext(), "com.globalauto_vip_service.fileprovider", file);
} else {
uri = Uri.fromFile(file);
}
return uri;
}

//如何获得图片回调的图片地址

Uri selectedImage = data.getData();
picturePath = getPath(Issue_Activity.this, selectedImage);

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

System.out.println("图片地址不为空：" + 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)) {
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));

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]
};

return getDataColumn(context, contentUri, selection, selectionArgs);
}
}
// MediaStore (and general)
else if (uri.getScheme() != null && "content".equalsIgnoreCase(uri.getScheme())) {

// Return the remote address
if (isGooglePhotosUri(uri))
return uri.getLastPathSegment();

return getDataColumn(context, uri, null, null);
}
// File
else if (uri.getScheme() != null && "file".equalsIgnoreCase(uri.getScheme())) {
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());
}

这样就可以得到相册返回的图片地址，

相机的回调图片地址就是mFilePath ；

我们可以用来得到对应的BITMAP，为什么我要得到地址而不是直接得到bitmap

因为我需要对原图片进行压缩Luban压缩工具

OK这个方法也是适合小米的

//--------end---------