Custom view for pin

gistfile1.txt

import android.annotation.TargetApi;
import android.app.Service;
import android.content.Context;
import android.content.res.TypedArray;
import android.os.Build;
import android.support.annotation.DrawableRes;
import android.text.Editable;
import android.text.InputFilter;
import android.text.InputType;
import android.text.TextWatcher;
import android.text.method.DigitsKeyListener;
import android.util.AttributeSet;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.LinearLayout;

public class PinView extends LinearLayout implements TextWatcher, View.OnClickListener {

    private int mFieldCount;
    private float mFieldSize;
    private float mFieldVerticalMargin;
    private float mFieldHorizontalMargin;

    private
    @DrawableRes
    int mDrawableEmpty;

    private
    @DrawableRes
    int mDrawableFilled;

    private EditText mEdiText;
    private ImageView[] mImageViews;

    private OnPinEnteredListener mListener;

    public PinView(Context context) {
        super(context);
        init(context, null, 0, 0);
    }

    public PinView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context, attrs, 0, 0);
    }

    public PinView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(context, attrs, defStyleAttr, 0);
    }

    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
    public PinView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
        init(context, attrs, defStyleAttr, defStyleRes);
    }

    private void init(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        TypedArray a = context.getTheme().obtainStyledAttributes(attrs,
                R.styleable.PinView, defStyleAttr, defStyleRes);
        try {
            mFieldCount = a.getInteger(R.styleable.PinView_fieldsCount, 4);
            mFieldSize = a.getDimension(R.styleable.PinView_field_size,
                    getResources().getDimension(R.dimen.pin_default_field_size));

            mFieldVerticalMargin = a.getDimension(R.styleable.PinView_field_vertical_margin,
                    getResources().getDimension(R.dimen.pin_default_field_vertical_margin));
            mFieldHorizontalMargin = a.getDimension(R.styleable.PinView_field_horizontal_margin,
                    getResources().getDimension(R.dimen.pin_default_field_horizontal_margin));

            mDrawableEmpty = a.getResourceId(R.styleable.PinView_drawable_empty, -1);
            mDrawableFilled = a.getResourceId(R.styleable.PinView_drawable_filled, -1);
        } finally {
            a.recycle();
        }

        initViews();
    }

    private void initViews() {
        this.setOrientation(HORIZONTAL);

        mEdiText = new EditText(getContext());
        mEdiText.setFilters(new InputFilter[]{new InputFilter.LengthFilter(mFieldCount)});
        mEdiText.setInputType(InputType.TYPE_CLASS_NUMBER);
        mEdiText.setKeyListener(DigitsKeyListener.getInstance("0123456789"));
        mEdiText.setLayoutParams(new LayoutParams(0, 1));

        mEdiText.addTextChangedListener(this);
        addView(mEdiText);

        mImageViews = new ImageView[mFieldCount];
        for (int i = 0; i < mFieldCount; i++) {
            ImageView imageView = new ImageView(getContext());

            LayoutParams params = new LayoutParams((int) mFieldSize, (int) mFieldSize);
            params.setMargins(
                    (int) mFieldHorizontalMargin,
                    (int) mFieldVerticalMargin,
                    (int) mFieldHorizontalMargin,
                    (int) mFieldVerticalMargin
            );
            imageView.setLayoutParams(params);
            imageView.setImageResource(mDrawableEmpty);

            mImageViews[i] = imageView;
            addView(mImageViews[i]);
        }

        setOnClickListener(this);
    }


    @Override
    public void beforeTextChanged(CharSequence text, int start, int count, int after) {
    }

    @Override
    public void afterTextChanged(Editable editable) {
    }

    @Override
    public void onTextChanged(CharSequence text, int start, int count, int after) {
        for (int i = 0; i < mFieldCount; i++) {
            mImageViews[i].setImageResource(text.length() > i ? mDrawableFilled : mDrawableEmpty);
        }

        if (text.length() == mFieldCount) {
            if (mListener != null)
                mListener.onEnter(text.toString());
        }
    }

    @Override
    public void onClick(View view) {
        mEdiText.requestFocus();
        InputMethodManager imm = (InputMethodManager) getContext().getSystemService(Service.INPUT_METHOD_SERVICE);
        imm.showSoftInput(mEdiText, 0);
    }

    public void clear() {
        mEdiText.setText("");
    }

    public OnPinEnteredListener getOnPinEnteredListener() {
        return mListener;
    }

    public void setOnPinEnteredListener(OnPinEnteredListener listener) {
        mListener = listener;
    }

    public interface OnPinEnteredListener {
        void onEnter(String pin);
    }
}