Нет простого способа сделать это, афаик.Компиляция из 9 патчей выполняется aapt и довольно проста: она отбрасывает черные границы и кодирует их содержимое внутри фрагмента PNG.Было бы довольно тривиально для вас написать инструмент, который делает что-то подобное.Обратите внимание, что вам даже не нужно использовать тот же формат.Если вы посмотрите на различные API-интерфейсы NinePatch в документе, вы увидите, что вы можете представить свой собственный «чанк» (который кодирует области растяжения и отступы). Структура массива байтов [] объясняется здесь:
/**
* This chunk specifies how to split an image into segments for
* scaling.
*
* There are J horizontal and K vertical segments. These segments divide
* the image into J*K regions as follows (where J=4 and K=3):
*
* F0 S0 F1 S1
* +-----+----+------+-------+
* S2| 0 | 1 | 2 | 3 |
* +-----+----+------+-------+
* | | | | |
* | | | | |
* F2| 4 | 5 | 6 | 7 |
* | | | | |
* | | | | |
* +-----+----+------+-------+
* S3| 8 | 9 | 10 | 11 |
* +-----+----+------+-------+
*
* Each horizontal and vertical segment is considered to by either
* stretchable (marked by the Sx labels) or fixed (marked by the Fy
* labels), in the horizontal or vertical axis, respectively. In the
* above example, the first is horizontal segment (F0) is fixed, the
* next is stretchable and then they continue to alternate. Note that
* the segment list for each axis can begin or end with a stretchable
* or fixed segment.
*
* The relative sizes of the stretchy segments indicates the relative
* amount of stretchiness of the regions bordered by the segments. For
* example, regions 3, 7 and 11 above will take up more horizontal space
* than regions 1, 5 and 9 since the horizontal segment associated with
* the first set of regions is larger than the other set of regions. The
* ratios of the amount of horizontal (or vertical) space taken by any
* two stretchable slices is exactly the ratio of their corresponding
* segment lengths.
*
* xDivs and yDivs point to arrays of horizontal and vertical pixel
* indices. The first pair of Divs (in either array) indicate the
* starting and ending points of the first stretchable segment in that
* axis. The next pair specifies the next stretchable segment, etc. So
* in the above example xDiv[0] and xDiv[1] specify the horizontal
* coordinates for the regions labeled 1, 5 and 9. xDiv[2] and
* xDiv[3] specify the coordinates for regions 3, 7 and 11. Note that
* the leftmost slices always start at x=0 and the rightmost slices
* always end at the end of the image. So, for example, the regions 0,
* 4 and 8 (which are fixed along the X axis) start at x value 0 and
* go to xDiv[0] and slices 2, 6 and 10 start at xDiv[1] and end at
* xDiv[2].
*
* The array pointed to by the colors field lists contains hints for
* each of the regions. They are ordered according left-to-right and
* top-to-bottom as indicated above. For each segment that is a solid
* color the array entry will contain that color value; otherwise it
* will contain NO_COLOR. Segments that are completely transparent
* will always have the value TRANSPARENT_COLOR.
*
* The PNG chunk type is "npTc".
*/
struct Res_png_9patch
{
Res_png_9patch() : wasDeserialized(false), xDivs(NULL),
yDivs(NULL), colors(NULL) { }
int8_t wasDeserialized;
int8_t numXDivs;
int8_t numYDivs;
int8_t numColors;
// These tell where the next section of a patch starts.
// For example, the first patch includes the pixels from
// 0 to xDivs[0]-1 and the second patch includes the pixels
// from xDivs[0] to xDivs[1]-1.
// Note: allocation/free of these pointers is left to the caller.
int32_t* xDivs;
int32_t* yDivs;
int32_t paddingLeft, paddingRight;
int32_t paddingTop, paddingBottom;
enum {
// The 9 patch segment is not a solid color.
NO_COLOR = 0x00000001,
// The 9 patch segment is completely transparent.
TRANSPARENT_COLOR = 0x00000000
};
// Note: allocation/free of this pointer is left to the caller.
uint32_t* colors;
// Convert data from device representation to PNG file representation.
void deviceToFile();
// Convert data from PNG file representation to device representation.
void fileToDevice();
// Serialize/Marshall the patch data into a newly malloc-ed block
void* serialize();
// Serialize/Marshall the patch data
void serialize(void* outData);
// Deserialize/Unmarshall the patch data
static Res_png_9patch* deserialize(const void* data);
// Compute the size of the serialized data structure
size_t serializedSize();
};