StringWidget.java

package org.commcare.views.widgets;

import android.content.Context;
import android.text.Editable;
import android.text.InputFilter;
import android.text.InputType;
import android.text.TextWatcher;
import android.text.method.PasswordTransformationMethod;
import android.text.method.TextKeyListener;
import android.text.method.TextKeyListener.Capitalize;
import android.util.TypedValue;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.inputmethod.EditorInfo;
import android.view.inputmethod.InputMethodManager;
import android.widget.EditText;

import org.commcare.dalvik.R;
import org.javarosa.core.model.condition.pivot.StringLengthRangeHint;
import org.javarosa.core.model.condition.pivot.UnpivotableExpressionException;
import org.javarosa.core.model.data.IAnswerData;
import org.javarosa.core.model.data.StringData;
import org.javarosa.form.api.FormEntryPrompt;

/**
 * The most basic widget that allows for entry of any text.
 *
 * @author Carl Hartung (carlhartung@gmail.com)
 * @author Yaw Anokwa (yanokwa@gmail.com)
 */
public class StringWidget extends QuestionWidget implements OnClickListener, TextWatcher {

    private boolean mReadOnly = false;
    protected final EditText mAnswer;
    protected boolean secret = false;

    public StringWidget(Context context, FormEntryPrompt prompt, boolean secret) {
        super(context, prompt);
        mAnswer = (EditText)LayoutInflater.from(getContext()).inflate(R.layout.edit_text_question_widget, this, false);
        mAnswer.setTextSize(TypedValue.COMPLEX_UNIT_DIP, mAnswerFontSize);
        mAnswer.setOnClickListener(this);

        mAnswer.addTextChangedListener(this);

        //Let's see if we can figure out a constraint for this string
        try {
            addAnswerFilter(new InputFilter.LengthFilter(guessMaxStringLength(prompt)));
        } catch (UnpivotableExpressionException e) {
            //expected if there isn't a constraint that does this
        }

        this.secret = secret;

        if (!secret) {
            // capitalize the first letter of the sentence
            mAnswer.setKeyListener(new TextKeyListener(Capitalize.SENTENCES, false));
        }
        setTextInputType(mAnswer);

        if (!secret) {
            mAnswer.setSingleLine(false);
        }

        if (prompt != null) {
            mReadOnly = prompt.isReadOnly();
            IAnswerData value = prompt.getAnswerValue();
            if (value != null) {
                mAnswer.setText(value.getDisplayText());
            }

            if (mReadOnly) {
                if (value == null) {
                    mAnswer.setText("---");
                }
                mAnswer.setBackgroundDrawable(null);
                mAnswer.setFocusable(false);
                mAnswer.setClickable(false);
            }
        }

        addView(mAnswer);
    }

    /**
     * Guess the max string length based on the datatypes.
     */
    protected int guessMaxStringLength(FormEntryPrompt prompt) throws UnpivotableExpressionException {
        StringLengthRangeHint hint = new StringLengthRangeHint();
        prompt.requestConstraintHint(hint);
        if (hint.getMax() != null) {
            //We can!
            int length = ((String)hint.getMax().getValue()).length();
            if (!hint.isMaxInclusive()) {
                length -= 1;
            }

            return length;
        }
        throw new UnpivotableExpressionException();
    }


    protected void addAnswerFilter(InputFilter filter) {
        //Let's add a filter
        InputFilter[] currentFilters = mAnswer.getFilters();
        InputFilter[] newFilters = new InputFilter[currentFilters.length + 1];
        System.arraycopy(currentFilters, 0, newFilters, 0, currentFilters.length);
        newFilters[currentFilters.length] = filter;

        mAnswer.setFilters(newFilters);
    }

    protected void setTextInputType(EditText mAnswer) {
        if (secret) {
            mAnswer.setInputType(InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_PASSWORD);
            mAnswer.setTransformationMethod(PasswordTransformationMethod.getInstance());
        } else {
            mAnswer.setInputType(InputType.TYPE_TEXT_VARIATION_FILTER);
        }
    }

    @Override
    public void clearAnswer() {
        mAnswer.setText(null);
    }


    @Override
    public IAnswerData getAnswer() {
        String s = mAnswer.getText().toString().trim();
        if (s == null || s.equals("")) {
            return null;
        } else {
            return new StringData(s);
        }
    }


    @Override
    public void setFocus(Context context) {

        // Put focus on text input field and display soft keyboard if appropriate.
        mAnswer.requestFocus();
        InputMethodManager inputManager =
                (InputMethodManager)context.getSystemService(Context.INPUT_METHOD_SERVICE);
        if (!mReadOnly) {
            inputManager.showSoftInput(mAnswer, 0);
            /*
             * If you do a multi-question screen after a "add another group" dialog, this won't
             * automatically pop up. It's an Android issue.
             * 
             * That is, if I have an edit text in an activity, and pop a dialog, and in that
             * dialog's button's OnClick() I call edittext.requestFocus() and
             * showSoftInput(edittext, 0), showSoftinput() returns false. However, if the edittext
             * is focused before the dialog pops up, everything works fine. great.
             */
        } else {
            inputManager.hideSoftInputFromWindow(mAnswer.getWindowToken(), 0);
        }
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        if (event.isAltPressed()) {
            return false;
        }
        widgetEntryChanged();
        return super.onKeyDown(keyCode, event);
    }


    @Override
    public void setOnLongClickListener(OnLongClickListener l) {
        mAnswer.setOnLongClickListener(l);
    }

    @Override
    public void unsetListeners() {
        super.unsetListeners();

        mAnswer.setOnLongClickListener(null);
    }

    @Override
    public void cancelLongPress() {
        super.cancelLongPress();
        mAnswer.cancelLongPress();
    }

    @Override
    public void onClick(View v) {
        //revert to default editor behavior
        setFocus(getContext());
        mAnswer.setImeOptions(EditorInfo.IME_ACTION_UNSPECIFIED);
    }

    @Override
    public void acceptFocus() {
        mAnswer.performClick();
    }

    @Override
    public void afterTextChanged(Editable s) {
        widgetEntryChanged();
    }

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count,
                                  int after) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
        // TODO Auto-generated method stub

    }

    public void setLastQuestion(boolean isLast) {
        // nothing changes for Strings
    }

    /**
     * For testing purposes
     */
    public void setAnswer(String answer) {
        mAnswer.setText(answer);
    }
}