Using PhoneGap FileWriter.write for "big" files
I found the answer.
Crash reason: PhoneGap FileWrite.write cannot handle too big buffer, do not know exact size, I think this issue is due to PG transfer data to iOS through URL Scheme, somehow it crash when "URL" is too long.
How to fix it: write small block every time, code below:
function gotFileWriter(writer) {
function writeFinish() {
// ... your done code here...
}
var written = 0;
var BLOCK_SIZE = 1*1024*1024; // write 1M every time of write
function writeNext(cbFinish) {
var sz = Math.min(BLOCK_SIZE, data.byteLength - written);
var sub = data.slice(written, written+sz);
writer.write(sub);
written += sz;
writer.onwrite = function(evt) {
if (written < data.byteLength)
writeNext(cbFinish);
else
cbFinish();
};
}
writeNext(writeFinish);
}
UPDATE Aug 12,2014:
In my practice, the performance of saving file through Cordova FileSystem is not good, especially for large file(>5M) on phone, it takes a few seconds. If you are downloading file from server to local disk, you may want a "efficient and direct" way, try cordova-plugin-file-transfer plugin.
@Imskull's answer is the correct one ... i just want to put in the one for Blob (make sure it is blob and not arraybuffer) which is updated based on the one on top ... what i also added was a line to assure myself i am adding to the end of file ... it is more than enough to make ur app stop crashing (on ios mainly :P )
function gotFileWriter(writer) {
function writeFinish() {
// ... your done code here...
}
var written = 0;
var BLOCK_SIZE = 1*1024*1024; // write 1M every time of write
function writeNext(cbFinish) {
writer.onwrite = function(evt) {
if (written < data.size)
writeNext(cbFinish);
else
cbFinish();
};
if (written) writer.seek(writer.length);
writer.write(data.slice(written, written + Math.min(BLOCK_SIZE, data.size - written)));
written += Math.min(BLOCK_SIZE, data.size - written);
}
writeNext(writeFinish);
}