19之前直接跳轉到：

intent.setAction(Intent.ACTION_GET_CONTENT);

intent.setType("image/*");

這個intent就可以，但是19之後如果再跳轉到這個頁面，然後又選擇了不存在與MediaStore資料庫中的圖片，那麼根據返回的uri進行解析就會發生錯誤。

所以需要適配一下，19之後跳轉到這個intent:

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

c此頁面只包含存在於MediaStore資料庫中的圖片，可有效防止找不到圖片的錯誤。

程式碼如下：

/**跳轉到系統相簿：適配19前後的系統*/
public static Intent getGalleryIntent(Intent intent)
{
    /**19之後的系統相簿的圖片都存在於MediaStore資料庫中；19之前的系統相簿中可能包含不存在與資料庫中的圖片，所以如果是19之上的系統
     * 跳轉到19之前的系統相簿選擇了一張不存在與資料庫中的圖片，解析uri時就可能會出現null*/
    if (Build.VERSION.SDK_INT < 19) {
        intent.setAction(Intent.ACTION_GET_CONTENT);
        intent.setType("image/*");
    } else {
        intent = new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
        intent.setDataAndType(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,"image/*");
    }
    return intent;
}

/**
 * 專為Android4.4設計的從Uri獲取檔案絕對路徑，以前的方法已不好使
 * 可以用在  解析 uri 資料的地方（相簿回傳資料）
 */
@SuppressLint("NewApi")
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];

            }

        }
        // 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 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 column_index = cursor.getColumnIndexOrThrow(column);
            return cursor.getString(column_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());

}