Replace gesture library templates in android

Question

Is it possible to replace a gesture template of template library from a running application? I am building a handwriting recognizer system in which there are templates of letters in gesture library file.So basically after loading the library inside the code i compare user input gesture like:

public void onGesturePerformed(GestureOverlayView overlay, Gesture gesture) {
ArrayList<Prediction> predictions = gesturelib.recognize(gesture);

   if (predictions.size() > 1) {
    for(Prediction prediction: predictions){
       //i compare prediction name here and if matches print it in an edittext
    }

This should work good until user will give the same pattern like i did during building the library template.But i want to give an user that flexibility to replace an template item with his handwritten pattern when there is a mismatch of prediction.

Because below 2 handwritten gesture samples are different in terms of pattern,but not as a letter.Suppose,my system supports the 1st image pattern,i want when user will give 2nd image pattern the system will ask confirmation from user to replace it with the library pattern of A and then replace it after confirm.So next time the system will recognize user pattern much better.

Any help would be greatly appreciated.

Answer 1

If I understand correctly, you want to replace an already existing gesture with a new one?

So, when the user inputs a gesture that isn't in the library, your app asks the user to select which gesture they wish to replace? From your question, I will assume that when user draws a lowercase a(and if a isn't in the library), user is presented with a list of all available gestures/letters that your app currently supports. And then, the user selects capital A, and now, capital A must be replaced with lowercase a. In the following code, oldGesture is the Gesture corresponding to A. And newGesture is the Gesture just drawn.

The process for that would be: delete the old gesture, add the new one using old gesture's name. To delete a gesture, use GestureLibrary.removeGesture(String, Gesture):

public void onGesturePerformed(GestureOverlayView overlay, final Gesture gesture) {

    ArrayList<Prediction> predictions = gesturelib.recognize(gesture);

    if (predictions.size() > 1) {

        for(Prediction prediction: predictions){

            if (prediction.score > ...) {

            } else {

                if (user wants to replace) {

                    showListWithAllGestures(gesture);
                }
            }
        }
    }
}

public void showListWithAllGestures(Gesture newGesture) {
    ....
    ....

    // User picks a gesture
    Gesture oldGesture = userPickedItem.gesture;
    String gestureName = userPickedItem.name;

    // delete the gesture
    gesturelib.removeGesture(gestureName, oldGesture);
    gesturelib.save();

    // add gesture
    gesturelib.addGesture(gestureName, newGesture);
    gesturelib.save();

}

To get a list of all available gestures:

// Wrapper to hold a gesture
static class GestureHolder {
    String name;
    Gesture gesture;
}

Load gestures using GestureLibrary.load():

if (gesturelib.load()) {

    for (String name : gesturelib.getGestureEntries()) {

        for (Gesture gesture : gesturelib.getGestures(name)) {

            final GestureHolder gestureHolder = new GestureHolder();
            gestureHolder.gesture = gesture;
            gestureHolder.name = name;

            // Add `gestureHolder` to a list

        }
    }

    // Return the list that holds GestureHolder objects

}

Edit:

Sorry, but the check I have suggested: if (wants to replace) is being carried out at the wrong place in code.

if (predictions.size() > 1) {

    // To check whether a match was found
    boolean gotAMatch = false;

    for(int i = 0; i < predictions.size() && !gotAMatch; i++){

        if (prediction.score > ... ) {

            ....
            ....

            // Found a match, look no more
            gotAMatch = true;

        }
    }

    // If a match wasn't found, ask the user s/he wants to add it
    if (!gotAMatch) {

        if (user wants to replace) {

            showListWithAllGestures(gesture);
        }
    }
}