❶ android怎么从sd卡指定的文件夹中获取所有图片的路径URL，谢谢～感谢各位大神了
直接调用文件管理器选择图片即可。
1、调用系统提供的图片选择器，代码如下：
//注意，在Android4.4系统下建议使用 Intent.ACTION_OPEN_DOCUMENT方式
if (Utility.isKK()) {
Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
intent.addCategory(Intent.CATEGORY_OPENABLE);
intent.setType("image
public static String getDataColumn(Context context, Uri uri, String selection,
String[] selectionArgs) {
Cursor cursor = null;
final String column = "_data";
final String[] projection = {
column
};
处理返回结果：
protected void onActivityResult(int requestCode, int resultCode,
Intent intent) {
super.onActivityResult(requestCode, resultCode, intent);
if (resultCode == RESULT_OK) {
switch (requestCode) {
case PIC_RESULT://选择图库
case PIC_RESULT_KK:
imageFileUri = intent.getData();//获取选择图片的URI
break;
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2、除此自外，系统还提供一种选择器，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.
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,主要区别是他们返回的Uri.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.可以通过以下方式，处理URI。
参考：Android 4.4从图库选择图片,获取图片路径并裁剪
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)) {
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 ("content".equalsIgnoreCase(uri.getScheme())) {
// Return the remote address
if (isGooglePhotosUri(uri))
return uri.getLastPathSegment();
return getDataColumn(context, uri, null, null);
}
// File
else if ("file".equalsIgnoreCase(uri.getScheme())) {
return uri.getPath();
}
return null;
}
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;
}
public static boolean isExternalStorageDocument(Uri uri) {
return "com.android.externalstorage.documents".equals(uri.getAuthority());
}
public static boolean isDownloadsDocument(Uri uri) {
return "com.android.providers.downloads.documents".equals(uri.getAuthority());
}
public static boolean isMediaDocument(Uri uri) {
return "com.android.providers.media.documents".equals(uri.getAuthority());
}
public static boolean isGooglePhotosUri(Uri uri) {
return "com.google.android.apps.photos.content".equals(uri.getAuthority());
}
3、使用其它开源组件如PhotoView。
❷ android怎么调用系统自带的图库打开指定目录的相册
使用系统自带的图片浏览器应用程序Gallery可以打开一张指定的图片，
//使用Intent
Intent intent = new Intent(Intent.ACTION_VIEW);
//Uri mUri = Uri.parse("file://" + picFile.getPath());Android3.0以后最好不要通过该方法，存在一些小Bug
intent.setDataAndType(Uri.fromFile(picFile), "image/*");
startActivity(intent）
❸ android怎么调用系统自带的图库打开指定目录的相册
//使用Intent来调滑脊用相信则渗册盯哗
Intent intent=new Intent(Intent.ACTION_PICK,MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
//使用startActivityForResult来调用相册界面startActivityForResult(intent, REQ_PICK_PICTURE_FROM_GALLERY);
❹ Android实现图库功能，查看本应用drawable下的所有图片，且能左右滑动切换上一页或下一页图片
使用ImageLoader
源码地址
https://github.com/nostra13/Android-Universal-Image-Loader
可以通过这个框架来加载以下类型的图片
"http://site.com/image.png" // from Web
"file:///mnt/sdcard/image.png" // from SD card
"file:///mnt/sdcard/video.mp4" // from SD card (video thumbnail)
"content://media/external/images/media/13" // from content provider
"content://media/external/video/media/13" // from content provider (video thumbnail)
"assets://image.png" // from assets
"drawable://" + R.drawable.img // from drawables (non-9patch images)
官网有例子,使用非常简单,一行代码搞定