Android 获取手机本地图片地址问题和解决方案

好了，思想+代码。

关于不能得到手机里图片问题分析：

1.获取的地址是否是绝对地址。

Java 工具类

/** * Created by aierJun */ public class ImageUtil { /** * Method for return file path of Gallery image * * @param context * @param uri * @return path of the selected image file from gallery */ @SuppressLint("NewApi") public static String getPath(final Context context, final Uri uri) { // check here to KITKAT or new version 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]; } } // 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; } /** * 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()); } }

2.读写权限是否授权

1.Android 6.0以下设备无需考虑

2.Android 6.0以上设备新特性

除了在manifest里面配置权限外，还必须动态授权，不然获取不到图片资源或者崩溃

解决方案一：

targetSdkVersion23改为22，降级。现在创建默认23.（不建议，不是最终方案）

解决方案二：

修改代码为动态授权（最终解决方案）

关于动态授权有时间会在下篇中做详细说明。