The title is explicit enough, I want to let the user choose the text file he want to open.
I do not know if there is an explorer or an input field already implemented on processing.
Any help would be great.
Use selectInput. From the Processing reference:
Opens a platform-specific file chooser dialog to select a file for input. After the selection is made, the selected File will be passed to the 'callback' function. If the dialog is closed or canceled, null will be sent to the function, so that the program is not waiting for additional input. The callback is necessary because of how threading works.
I've modified the example sketch they provide in the reference to include loading the file with the loadStrings method.
String[] txtFile;
void setup() {
selectInput("Select a file to process:", "fileSelected");
}
void fileSelected(File selection) {
if (selection == null) {
println("Window was closed or the user hit cancel.");
} else {
String filepath = selection.getAbsolutePath();
println("User selected " + filepath);
// load file here
txtFile = loadStrings(filepath);
}
}
There is no Implemented method, but you could could make a buffer and monitor key presses like so:
String[] File;
String keybuffer = "";
Char TriggerKey = Something;
void setup(){
//do whatever here
}
void draw(){
//Optional, to show the current buffer
background(255);
text(keybuffer,100,100);
}
void keyPressed(){
if(keyCode >= 'a' && keyCode <= 'z'){
keybuffer = keybuffer + key;
}
if(key == TriggerKey){
File = loadStrings(keybuffer + ".txt");
}
}
when triggerkey is pressed, it loads the file
Related
I'm working on a typing program to learn touch typing and increase speed.
The program generates random words in the textbox (txtsrc) and the user must type the word in another textbox(txtinput) everything is going right until I stuck in this problem: I want to compare every char in txtinput when the user hit the key down if the key is correct to keep going if not change the color of char in txtsrc to red.
how can I allow the user to use the backspace to remove his errs
and how to compare the chars while the user input the text
I can't find the right algorithm please help
private void txtinput_KeyUp(object sender, KeyEventArgs e)
{
if (keycount < 0) { keycount++; }
if (e.KeyCode == Keys.Back)
{
--keycount;
txtsrc.Select(keycount, 1);
txtsrc.SelectionColor = Color.Black;
}
if (keycount >= 0 && txtinput.Text.Length > 0)
if (txtsrc.Text[keycount] != txtinput.Text[txtinput.Text.Length - 1])
{
txtsrc.Select(keycount, 1);
txtsrc.SelectionColor = Color.Red;
}
if (e.KeyCode != Keys.Back)
{
keycount++;
label1.Text = "Keycount: " + keycount.ToString();
}
}
This is the event handlers i implemented to the copy, paste and Cut buttons in my MFCRibbonBar:
in the MyRibbonView.cpp:
void CMyRibbonView::OnEditCopy()
{
CWnd *wnd = GetFocus();
if (wnd == pEdit)
pEdit->Copy();
if (!OpenClipboard())
{
AfxMessageBox(_T("Cannot open the Clipboard"));
return;
}
if (!EmptyClipboard())
{
AfxMessageBox(_T("Cannot empty the Clipboard"));
return;
}
HGLOBAL hGlob = GlobalAlloc(GMEM_FIXED, 64);
strcpy_s((char*)hGlob, 64, "Current selection\r\n");
if (::SetClipboardData(CF_TEXT, hGlob) == NULL)
{
CString msg;
msg.Format(_T("Unable to set Clipboard data, error: %d"), GetLastError());
AfxMessageBox(msg);
CloseClipboard();
GlobalFree(hGlob);
return;
}
CloseClipboard();
}
void CMyRibbonView::OnEditPaste()
{
if (OpenClipboard())
{
HANDLE hClipboardData = GetClipboardData(CF_TEXT);
char *pchData = (char*)GlobalLock(hClipboardData);
CString strFromClipboard;
strFromClipboard = pchData;
pEdit->SetWindowText(strFromClipboard);
GlobalUnlock(hClipboardData);
CloseClipboard();
}
}
void CMyRibbonView::OnEditCut()
{
OnEditCopy();
pEdit->SetWindowText(L" ");
}
There is no errors, it's just not working. I tested it by adding the messages to check if it's actually the data or not but they're not popping up.
You need to GlobalLock your hGlob memory before copying your character string into it (this operation converts it into a usable pointer for your process - see here), and then call GlobalUnlock after you've done that (so that the clipboard can access hGlob):
HGLOBAL hGlob = GlobalAlloc(GMEM_FIXED, 64); // Maybe also need GMEM_MOVEABLE here instead?
char* cCopy = (char*)GlobalLock(hGlob);
strcpy_s(cGlob, 64, "Current selection\r\n");
GlobalUnlock(hGlob);
if (::SetClipboardData(CF_TEXT, hGlob) == NULL)
{
//...
And you'll need a similar arrangement for the paste operation.
UPDATE: The initial question has been answered as to why the crashes happen but the lingering problem remains of why is the 'OnImageAvailable' callback called so may times? When it is called, I want to do stuff with the image, but whatever method I run at that time is called many times. Is this the wrong place to be using the resulting image?
I am using the sample code found here for a Xamarin Android implementation of the Android Camera2 API. My issue is that when the capture button is pressed a single time, the OnCameraAvalibleListener's OnImageAvailable callback gets called multiple times.
This is causing a problem because the image from AcquireNextImage needs to be closed before another can be used, but close is not called until the Run method of the ImageSaver class as seen below.
This causes these 2 errors:
Unable to acquire a buffer item, very likely client tried to acquire
more than maxImages buffers
AND
maxImages (2) has already been acquired, call #close before acquiring
more.
The max image is set to 2 by default, but setting it to 1 does not help. How do I prevent the callback from being called twice?
public void OnImageAvailable(ImageReader reader)
{
var image = reader.AcquireNextImage();
owner.mBackgroundHandler.Post(new ImageSaver(image, file));
}
// Saves a JPEG {#link Image} into the specified {#link File}.
private class ImageSaver : Java.Lang.Object, IRunnable
{
// The JPEG image
private Image mImage;
// The file we save the image into.
private File mFile;
public ImageSaver(Image image, File file)
{
if (image == null)
throw new System.ArgumentNullException("image");
if (file == null)
throw new System.ArgumentNullException("file");
mImage = image;
mFile = file;
}
public void Run()
{
ByteBuffer buffer = mImage.GetPlanes()[0].Buffer;
byte[] bytes = new byte[buffer.Remaining()];
buffer.Get(bytes);
using (var output = new FileOutputStream(mFile))
{
try
{
output.Write(bytes);
}
catch (IOException e)
{
e.PrintStackTrace();
}
finally
{
mImage.Close();
}
}
}
}
The method OnImageAvailable can be called again as soon as you leave it if there is another picture in the pipeline.
I would recommend calling Close in the same method you are calling AcquireNextImage. So, if you choose to get the image directly from that callback, then you have to call Close in there as well.
One solution involved grabbing the image in that method and close it right away.
public void OnImageAvailable(ImageReader reader)
{
var image = reader.AcquireNextImage();
try
{
ByteBuffer buffer = mImage.GetPlanes()[0].Buffer;
byte[] bytes = new byte[buffer.Remaining()];
buffer.Get(bytes);
// I am not sure where you get the file instance but it is not important.
owner.mBackgroundHandler.Post(new ImageSaver(bytes, file));
}
finally
{
image.Close();
}
}
The ImageSaver would be modified to accept the byte array as first parameter in the constructor:
public ImageSaver(byte[] bytes, File file)
{
if (bytes == null)
throw new System.ArgumentNullException("bytes");
if (file == null)
throw new System.ArgumentNullException("file");
mBytes = bytes;
mFile = file;
}
The major downside of this solution is the risk of putting a lot of pressure on the memory as you basically save the images in memory until they are processed, one after another.
Another solution consists in acquiring the image on the background thread instead.
public void OnImageAvailable(ImageReader reader)
{
// Again, I am not sure where you get the file instance but it is not important.
owner.mBackgroundHandler.Post(new ImageSaver(reader, file));
}
This solution is less intensive on the memory; but you might have to increase the maximum number of images from 2 to something higher depending on your needs. Again, the ImageSaver's constructor needs to be modified to accept an ImageReader as a parameter:
public ImageSaver(ImageReader imageReader, File file)
{
if (imageReader == null)
throw new System.ArgumentNullException("imageReader");
if (file == null)
throw new System.ArgumentNullException("file");
mImageReader = imageReader;
mFile = file;
}
Now the Run method would have the responsibility of acquiring and releasing the Image:
public void Run()
{
Image image = mImageReader.AcquireNextImage();
try
{
ByteBuffer buffer = image.GetPlanes()[0].Buffer;
byte[] bytes = new byte[buffer.Remaining()];
buffer.Get(bytes);
using (var output = new FileOutputStream(mFile))
{
try
{
output.Write(bytes);
}
catch (IOException e)
{
e.PrintStackTrace();
}
}
}
finally
{
image?.Close();
}
}
I too facing this issue for longer time and tried implementing #kzrytof's solution but didn't helped well as expected but found the way to get the onImageAvailable to execute once.,
Scenario: When the image is available then the onImageAvailable method is called right?
so, What I did is after closing the image using image.close(); I called the imagereader.setonImageAvailableListener() and made the listener = null. this way I stopped the execution for second time.,
I know, that your question is for xamarin and my below code is in native android java but the method and functionalities are same, so try once:
#Override
public void onImageAvailable(ImageReader reader) {
final Image image=imageReader.acquireLatestImage();
try {
if (image != null) {
Image.Plane[] planes = image.getPlanes();
ByteBuffer buffer = planes[0].getBuffer();
int pixelStride = planes[0].getPixelStride();
int rowStride = planes[0].getRowStride();
int rowPadding = rowStride - pixelStride * width;
int bitmapWidth = width + rowPadding / pixelStride;
if (latestBitmap == null ||
latestBitmap.getWidth() != bitmapWidth ||
latestBitmap.getHeight() != height) {
if (latestBitmap != null) {
latestBitmap.recycle();
}
}
latestBitmap.copyPixelsFromBuffer(buffer);
}
}
catch(Exception e){
}
finally{
image.close();
imageReader.setOnImageAvailableListener(null, svc.getHandler());
}
// next steps to save the image
}
I have a pdf which contains a lot of invisible paths. Since the amount of path produces problems later on, I would like to remove the ones that have white colors.
So far I am trying to do this with a ContentScanner:
public class FilterWhitePathScanner implements Scanner {
private static final Logger LOG = LoggerFactory.getLogger(FilterWhitePathScanner.class);
private int count = 0;
public void scan(ContentScanner level) {
if (level == null)
return;
while (level.moveNext()) {
ContentObject object = level.getCurrent();
if (object instanceof ContainerObject) {
// Scan the inner level!
scan(level.getChildLevel());
} else if (object instanceof org.pdfclown.documents.contents.objects.Path) {
AffineTransform ctm = level.getState().getCtm();
Color<?> strokeColor = level.getState().getStrokeColor();
Color<?> fillColor = level.getState().getFillColor();
if (checkWhite(fillColor) && checkWhite(strokeColor)) {
level.remove();
} else {
LOG.info("Stroke Color " + strokeColor + " - Fill Color " + fillColor);
}
} else {
LOG.info("Object:" + object);
}
}
}
It recognizes the paths correctly, but in the end these are not removed from the PDF. Here the code handling the PDF (it extracts only one page from the source pdf):
Document targetDoc = new File().getDocument();
targetDoc.getPages().add(sourceDoc.getPages().get(pageNum).clone(targetDoc));
Page page = targetDoc.getPages().get(0);
Contents contents = page.getContents();
FilterWhitePathScanner filterWhitePathScanner = new FilterWhitePathScanner();
filterWhitePathScanner.scan(new ContentScanner(contents));
LOG.info("White Paths: " + filterWhitePathScanner.getCount());
targetDoc.getFile().save(tempFilePath.toFile(), SerializationModeEnum.Standard);
The saved PDF file still contains the paths I tried to remove. How can I remove objects from the PDF finally?
Thanks,
Thomas
Finally found the solution in the Java doc:
You have to call contents.flush(); to persist the changes into the pdf file.
So I added this line to the PDF handling code before calling save and it works!
I have a listview that I want to update with information from a textfile (rollcall.txt). Each time rollcall.txt is updated I am calling rollcall() (code below). The data is updated correctly in the text file before rollcall() is called, I have checked. The problem I have is that the listview doesnt show the updated entry until the next time I call rollcall() (I.E it always appears to be one update step behind).
Where am I going wrong?
public void rollcall(){
String[] splitdata = null;
try{
File myFile = new File(Environment.getExternalStorageDirectory() + "/rollcall.txt");
FileInputStream fIn = new FileInputStream(myFile);
BufferedReader myReader = new BufferedReader(
new InputStreamReader(fIn));
String aDataRow = "";
String aBuffer = "";
while ((aDataRow = myReader.readLine()) != null) {
aBuffer += aDataRow + "\n";
}
splitdata = aBuffer.split("`"); //recover the file and split it based on `
myReader.close();
}
catch (Exception e) {
Toast.makeText(getBaseContext(), e.getMessage(),
Toast.LENGTH_SHORT).show();
}
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, R.layout.logbooklayout, splitdata);
lv1.setAdapter(adapter);
adapter.notifyDataSetChanged(); //called to ensure updated data is refreshed into listview without reload
EDIT: rollcall is called from this method:
public void onClick(View v) {
if (v==badd){
AlertDialog.Builder alert = new AlertDialog.Builder(this);
alert.setTitle("ROLLCALL"); //Set Alert dialog title here
alert.setMessage("Enter data: "); //Message here
// Set an EditText view to get user input
final EditText input = new EditText(this);
alert.setView(input);
alert.setPositiveButton("OK", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
//You will get as string input data in this variable.
// here we convert the input to a string and show in a toast.
add = input.getEditableText().toString();
try {
File myFile = new File(Environment.getExternalStorageDirectory() + "/rollcall.txt");
myFile.createNewFile();
FileOutputStream fOut = new FileOutputStream(myFile, true);
OutputStreamWriter myOutWriter = new OutputStreamWriter(fOut);
myOutWriter.append(add);
myOutWriter.append("`"); // ` used to split the file down later in lv section
myOutWriter.close();
fOut.close();
}
catch (Exception e) {
Toast.makeText(getBaseContext(), e.getMessage(),
Toast.LENGTH_SHORT).show();
}
} // End of onClick(DialogInterface dialog, int whichButton)
}); //End of alert.setPositiveButton
alert.setNegativeButton("CANCEL", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
// Canceled.
dialog.cancel();
}
}); //End of alert.setNegativeButton
AlertDialog alertDialog = alert.create();
alertDialog.show();
rollcall();
}//end badd
}
Thanks for the help, I am new to using arrayadapters.
Andy
Short answer to your question is everything in UI thread is asynchronous and unless you somehow manage to freeze/lock the whole application you can't make the rest of your UI wait for your alert to grab the input. So long before you press "OK" button in your alert, your rollcall() method is being called from your onClick() function and whatever is inside your .txt file is being read/displayed on your UI, right behind your alert dialog hanging on for you to press one of the buttons, asynchronously.
Maybe the fastest solution to what you want to achieve is to call your rollcall() function somewhere else, after you confirm that your adapter's feeding data has actually been changed. If you must call it from within onClick() function, without questioning your reasons to do so, you should call it inside the try{} block, right after you close the output stream.
Like this:
try {
File myFile = new File(Environment
.getExternalStorageDirectory() + "/rollcall.txt");
myFile.createNewFile();
FileOutputStream fOut = new FileOutputStream(myFile, true);
OutputStreamWriter myOutWriter = new OutputStreamWriter(
fOut);
myOutWriter.append(add);
myOutWriter.append("`"); // ` used to split the
// file down later
// in lv section
myOutWriter.close();
fOut.close();
rollcall();
}
The reason this "works" is you already declared the listener for your "OK" button and whenever you press it, whatever inside your EditText input will be written on file. In order to make it work as before I think you need superhuman skills to write some text on alert dialog and click on button before rollcall() function is called in the same scope.
Obviously the better way to do update the list view is to be able to use adapter.notifyDataSetChanged() but I believe you should call it somewhere else than where you write on your file and in that case your adapter must be declared outside the scope of rollcall() function.
Anyways in order to show how it all goes on I created a simple(rather ugly) android application and put some logs on where the mysterious stuff is happening:
public class MainActivity extends Activity {
private ListView lv1;
private Button refreshButton;
ArrayAdapter<String> adapter;
String[] splitdata;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
refreshButton = (Button) findViewById(R.id.refreshButton);
lv1 = (ListView) findViewById(R.id.someTextViewId);
refreshButton.setOnClickListener(myButtonhandler);
splitdata = null;
}
View.OnClickListener myButtonhandler = new View.OnClickListener() {
public void onClick(View v) {
Log.d("main", "la noliy");
someFunction();
}
};
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public void someFunction() {
AlertDialog.Builder alert = new AlertDialog.Builder(this);
alert.setTitle("ROLLCALL"); // Set Alert dialog title here
alert.setMessage("Enter data: "); // Message here
// Set an EditText view to get user input
final EditText input = new EditText(this);
alert.setView(input);
alert.setPositiveButton("OK", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
// You will get as string input data in this
// variable.
// here we convert the input to a string and show in
// a toast.
String add = input.getEditableText().toString();
try {
File myFile = new File(Environment
.getExternalStorageDirectory() + "/rollcall.txt");
myFile.createNewFile();
FileOutputStream fOut = new FileOutputStream(myFile, true);
OutputStreamWriter myOutWriter = new OutputStreamWriter(
fOut);
myOutWriter.append(add);
myOutWriter.append("`"); // ` used to split the
// file down later
// in lv section
myOutWriter.close();
fOut.close();
if (splitdata.length > 0) {
rollcall(new String("call from inside"));
}
} catch (Exception e) {
Toast.makeText(getBaseContext(), e.getMessage(),
Toast.LENGTH_SHORT).show();
}
} // End of onClick(DialogInterface dialog, int
// whichButton)
}); // End of alert.setPositiveButton
alert.setNegativeButton("CANCEL",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
// Canceled.
dialog.cancel();
}
}); // End of alert.setNegativeButton
AlertDialog alertDialog = alert.create();
alertDialog.show();
Log.d("someFunction", "before rollcall");
Log.d("someFunction", "location: "
+ Environment.getExternalStorageDirectory().getAbsolutePath());
rollcall(new String("call from outside"));
Log.d("someFunction", "after rollcall");
}// end badd
public void rollcall(String message) {
Log.d("rollcall", message);
try {
File myFile = new File(Environment.getExternalStorageDirectory()
+ "/rollcall.txt");
FileInputStream fIn = new FileInputStream(myFile);
BufferedReader myReader = new BufferedReader(new InputStreamReader(
fIn));
String aDataRow = "";
String aBuffer = "";
while ((aDataRow = myReader.readLine()) != null) {
aBuffer += aDataRow + "\n";
}
splitdata = aBuffer.split("`"); // recover the file and split it
// based on `
myReader.close();
} catch (Exception e) {
Toast.makeText(getBaseContext(), e.getMessage(), Toast.LENGTH_SHORT)
.show();
}
int length = splitdata.length;
for (int i = 0; i < length; i++) {
Log.d("rollcall", splitdata[i]);
}
adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, splitdata);
lv1.setAdapter(adapter);
}
}
I put a button and an onClickListener to it. The first time you press the button everything is called, listview is updated and your dialog is hanging on your screen for either of the buttons to be pressed:
And you will see a log like this:
07-26 04:09:20.802: D/someFunction(11273): before rollcall
07-26 04:09:20.802: D/someFunction(11273): location: /mnt/sdcard
07-26 04:09:20.802: D/rollcall(11273): call from outside
07-26 04:09:20.802: D/rollcall(11273): some data
07-26 04:09:20.802: D/rollcall(11273): some other data
07-26 04:09:20.812: D/someFunction(11273): after rollcall
You can see that rollcall() has been called from outside and not inside of your try/catch block since there is also another call from there to rollcall(). But when you press the button your try/catch block will do it's job inside your onClick() function and rollcall() will be called afterwards. Hence your listview wil be updated with new data you just entered in the dialog:
Here is the final part of log right after you press "OK" you can see that rollcall() is being called and it can read the new data:
07-26 04:09:46.347: D/rollcall(11273): call from inside
07-26 04:09:46.357: D/rollcall(11273): some data
07-26 04:09:46.357: D/rollcall(11273): some other data
07-26 04:09:46.357: D/rollcall(11273): new data
Finally, I'm sure there are a lot of ugliness in this whole approach to your problem. Bottom line is you need to know that everything happening in the UI thread is asynchronous and no one is waiting for you to enter data inside your dialog in that onClick() function. You should update your listview somewhere else with a more elegant approach in case your application throws an exception for example around that try/catch block. At least maybe you should add a finally{} block at the end of it and update your listview in there even though the try part fails. Hope this answered your question:)
PS. For those who want to try this at home, remember to provide a TextView id from your layout.xml file to the findViewById() function to get the ListView reference in your code, not an actual ListView id. Yeah, I know...
call adapter.notifyDataSetChanged() everytime you update your adapter, then listview will automatically be updated
I suggest you run rollcall as an asychronous task for 2 reasons. First, it will not stop your UI when rollcall() is running.
Second, you will be able to call onPostExecute(Object o) wher you can call `adapter.notifyDataSetChanged(); '