protected void setState(CalculatorState state) {
if (mCurrentState != state) {
mCurrentState = state;
invalidateEqualsButton();
if (state == CalculatorState.RESULT || state == CalculatorState.ERROR) {
mDeleteButton.setVisibility(View.GONE);
mClearButton.setVisibility(View.VISIBLE);
} else {
mDeleteButton.setVisibility(View.VISIBLE);
mClearButton.setVisibility(View.GONE);
}
if (state == CalculatorState.ERROR) {
final int errorColor = getResources().getColor(R.color.calculator_error_color);
mFormulaEditText.setTextColor(errorColor);
mResultEditText.setTextColor(errorColor);
if (android.os.Build.VERSION.SDK_INT >= 21) {
getWindow().setStatusBarColor(errorColor);
}
} else {
mFormulaEditText.setTextColor(getResources().getColor(R.color.display_formula_text_color));
mResultEditText.setTextColor(getResources().getColor(R.color.display_result_text_color));
if (android.os.Build.VERSION.SDK_INT >= 21) {
getWindow().setStatusBarColor(getResources().getColor(R.color.calculator_accent_color));
}
}
}
}
/**
* Inserts text into the formula EditText. If an equation was recently solved, it will replace the
* formula's text instead of appending.
*/
protected void insert(String text) {
// Add left parenthesis after functions.
if (mCurrentState.equals(CalculatorState.INPUT)
|| mCurrentState.equals(CalculatorState.GRAPHING)
|| mFormulaEditText.isCursorModified()) {
mFormulaEditText.insert(text);
} else {
mFormulaEditText.setText(text);
incrementGroupId();
}
}
private void onEquals() {
String text = mFormulaEditText.getCleanText();
if (mCurrentState == CalculatorState.INPUT) {
switch (mEqualButton.getState()) {
case EQUALS:
setState(CalculatorState.EVALUATE);
mEvaluator.evaluate(text, this);
break;
case NEXT:
mFormulaEditText.next();
break;
}
} else if (mCurrentState == CalculatorState.GRAPHING) {
setState(CalculatorState.EVALUATE);
onEvaluate(text, "", INVALID_RES_ID);
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_calculator);
savedInstanceState = savedInstanceState == null ? Bundle.EMPTY : savedInstanceState;
initialize(savedInstanceState);
mEvaluator.evaluate(mFormulaEditText.getCleanText(), this);
}
@Override
public void onEvaluate(String expr, String result, int errorResourceId) {
if (mCurrentState == CalculatorState.INPUT || mCurrentState == CalculatorState.GRAPHING) {
if (result == null || Solver.equal(result, expr)) {
mResultEditText.setText(null);
} else {
mResultEditText.setText(result);
}
} else if (errorResourceId != INVALID_RES_ID) {
onError(errorResourceId);
} else if (saveHistory(expr, result, true)) {
mDisplayView.scrollToMostRecent();
onResult(result);
} else if (mCurrentState == CalculatorState.EVALUATE) {
// The current expression cannot be evaluated -> return to the input state.
setState(CalculatorState.INPUT);
}
invalidateEqualsButton();
}
public void onButtonClick(View view) {
mCurrentButton = view;
switch (view.getId()) {
case R.id.eq:
onEquals();
break;
case R.id.del:
onDelete();
break;
case R.id.clr:
onClear();
break;
case R.id.parentheses:
mFormulaEditText.setText('(' + mFormulaEditText.getCleanText() + ')');
break;
case R.id.fun_cos:
case R.id.fun_sin:
case R.id.fun_tan:
case R.id.fun_ln:
case R.id.fun_log:
case R.id.fun_det:
case R.id.fun_transpose:
case R.id.fun_inverse:
case R.id.fun_trace:
case R.id.fun_norm:
case R.id.fun_polar:
// Add left parenthesis after functions.
insert(((Button) view).getText() + "(");
break;
case R.id.op_add:
case R.id.op_sub:
case R.id.op_mul:
case R.id.op_div:
case R.id.op_fact:
case R.id.op_pow:
mFormulaEditText.insert(((Button) view).getText().toString());
break;
default:
insert(((Button) view).getText().toString());
break;
}
}
@Override
protected void onSaveInstanceState(@NonNull Bundle outState) {
// If there's an animation in progress, cancel it first to ensure our state is up-to-date.
if (mCurrentAnimator != null) {
mCurrentAnimator.cancel();
}
super.onSaveInstanceState(outState);
outState.putInt(KEY_CURRENT_STATE, mCurrentState.ordinal());
outState.putString(
KEY_CURRENT_EXPRESSION,
mTokenizer.getNormalizedExpression(mFormulaEditText.getCleanText()));
}
protected void onClear() {
if (TextUtils.isEmpty(mFormulaEditText.getCleanText())) {
return;
}
reveal(
mCurrentButton,
R.color.calculator_accent_color,
new AnimationFinishedListener() {
@Override
public void onAnimationFinished() {
mFormulaEditText.clear();
incrementGroupId();
}
});
}
@Override
public boolean onLongClick(View view) {
mCurrentButton = view;
switch (view.getId()) {
case R.id.del:
saveHistory(mFormulaEditText.getCleanText(), mResultEditText.getCleanText(), true);
onClear();
return true;
case R.id.lparen:
case R.id.rparen:
mFormulaEditText.setText('(' + mFormulaEditText.getCleanText() + ')');
return true;
case R.id.fun_sin:
insert(getString(R.string.fun_arcsin) + "(");
return true;
case R.id.fun_cos:
insert(getString(R.string.fun_arccos) + "(");
return true;
case R.id.fun_tan:
insert(getString(R.string.fun_arctan) + "(");
return true;
}
return false;
}
protected void initialize(Bundle savedInstanceState) {
// Rebuild constants. If the user changed their locale, it won't kill the app
// but it might change a decimal point from . to ,
Constants.rebuildConstants();
mDisplayView = (DisplayOverlay) findViewById(R.id.display);
mDisplayView.setFade(findViewById(R.id.history_fade));
mDisplayForeground = (ViewGroup) findViewById(R.id.the_clear_animation);
mFormulaEditText = (CalculatorEditText) findViewById(R.id.formula);
mResultEditText = (CalculatorEditText) findViewById(R.id.result);
mPadViewPager = (CalculatorPadView) findViewById(R.id.pad_pager);
mDeleteButton = findViewById(R.id.del);
mClearButton = findViewById(R.id.clr);
mEqualButton = (EqualsImageButton) findViewById(R.id.pad_numeric).findViewById(R.id.eq);
if (mEqualButton == null || mEqualButton.getVisibility() != View.VISIBLE) {
mEqualButton = (EqualsImageButton) findViewById(R.id.pad_operator).findViewById(R.id.eq);
}
mTokenizer = new CalculatorExpressionTokenizer(this);
mEvaluator = new CalculatorExpressionEvaluator(mTokenizer);
setState(
CalculatorState.values()[
savedInstanceState.getInt(KEY_CURRENT_STATE, CalculatorState.INPUT.ordinal())]);
mFormulaEditText.setSolver(mEvaluator.getSolver());
mResultEditText.setSolver(mEvaluator.getSolver());
mFormulaEditText.setText(
mTokenizer.getLocalizedExpression(
savedInstanceState.getString(KEY_CURRENT_EXPRESSION, "")));
mFormulaEditText.addTextChangedListener(mFormulaTextWatcher);
mFormulaEditText.setOnKeyListener(mFormulaOnKeyListener);
mFormulaEditText.setOnTextSizeChangeListener(this);
mDeleteButton.setOnLongClickListener(this);
mResultEditText.setEnabled(false);
findViewById(R.id.lparen).setOnLongClickListener(this);
findViewById(R.id.rparen).setOnLongClickListener(this);
findViewById(R.id.fun_sin).setOnLongClickListener(this);
findViewById(R.id.fun_cos).setOnLongClickListener(this);
findViewById(R.id.fun_tan).setOnLongClickListener(this);
// Disable IME for this application
getWindow()
.setFlags(
WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM,
WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM);
Button dot = (Button) findViewById(R.id.dec_point);
dot.setText(String.valueOf(Constants.DECIMAL_POINT));
}
protected void onError(final int errorResourceId) {
if (mCurrentState != CalculatorState.EVALUATE) {
// Only animate error on evaluate.
mResultEditText.setText(errorResourceId);
return;
}
reveal(
mCurrentButton,
R.color.calculator_error_color,
new AnimationFinishedListener() {
@Override
public void onAnimationFinished() {
setState(CalculatorState.ERROR);
mResultEditText.setText(errorResourceId);
}
});
}
protected void onResult(final String result) {
// Calculate the values needed to perform the scale and translation animations,
// accounting for how the scale will affect the final position of the text.
final float resultScale =
mFormulaEditText.getVariableTextSize(result) / mResultEditText.getTextSize();
final float resultTranslationX =
(1.0f - resultScale)
* (mResultEditText.getWidth() / 2.0f - mResultEditText.getPaddingRight());
// Calculate the height of the formula (without padding)
final float formulaRealHeight =
mFormulaEditText.getHeight()
- mFormulaEditText.getPaddingTop()
- mFormulaEditText.getPaddingBottom();
// Calculate the height of the resized result (without padding)
final float resultRealHeight =
resultScale
* (mResultEditText.getHeight()
- mResultEditText.getPaddingTop()
- mResultEditText.getPaddingBottom());
// Now adjust the result upwards!
final float resultTranslationY =
// Move the result up (so both formula + result heights match)
-mFormulaEditText.getHeight()
// Now switch the result's padding top with the formula's padding top
- resultScale * mResultEditText.getPaddingTop()
+ mFormulaEditText.getPaddingTop()
// But the result centers its text! And it's taller now! So adjust for that centered
// text
+ (formulaRealHeight - resultRealHeight) / 2;
// Move the formula all the way to the top of the screen
final float formulaTranslationY = -mFormulaEditText.getBottom();
// Use a value animator to fade to the final text color over the course of the animation.
final int resultTextColor = mResultEditText.getCurrentTextColor();
final int formulaTextColor = mFormulaEditText.getCurrentTextColor();
final ValueAnimator textColorAnimator =
ValueAnimator.ofObject(new ArgbEvaluator(), resultTextColor, formulaTextColor);
textColorAnimator.addUpdateListener(
new AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator valueAnimator) {
mResultEditText.setTextColor((Integer) valueAnimator.getAnimatedValue());
}
});
mResultEditText.setText(result);
mResultEditText.setPivotX(mResultEditText.getWidth() / 2);
mResultEditText.setPivotY(0f);
final AnimatorSet animatorSet = new AnimatorSet();
animatorSet.playTogether(
textColorAnimator,
ObjectAnimator.ofFloat(mResultEditText, View.SCALE_X, resultScale),
ObjectAnimator.ofFloat(mResultEditText, View.SCALE_Y, resultScale),
ObjectAnimator.ofFloat(mResultEditText, View.TRANSLATION_X, resultTranslationX),
ObjectAnimator.ofFloat(mResultEditText, View.TRANSLATION_Y, resultTranslationY),
ObjectAnimator.ofFloat(mFormulaEditText, View.TRANSLATION_Y, formulaTranslationY));
animatorSet.setDuration(getResources().getInteger(android.R.integer.config_longAnimTime));
animatorSet.setInterpolator(new AccelerateDecelerateInterpolator());
animatorSet.addListener(
new AnimationFinishedListener() {
@Override
public void onAnimationFinished() {
// Reset all of the values modified during the animation.
mResultEditText.setPivotY(mResultEditText.getHeight() / 2);
mResultEditText.setTextColor(resultTextColor);
mResultEditText.setScaleX(1.0f);
mResultEditText.setScaleY(1.0f);
mResultEditText.setTranslationX(0.0f);
mResultEditText.setTranslationY(0.0f);
mFormulaEditText.setTranslationY(0.0f);
// Finally update the formula to use the current result.
mFormulaEditText.setText(result);
setState(CalculatorState.RESULT);
}
});
play(animatorSet);
}
protected void onDelete() {
// Delete works like backspace; remove the last character from the expression.
mFormulaEditText.backspace();
}
@Override
protected void onPause() {
super.onPause();
saveHistory(mFormulaEditText.getCleanText(), mResultEditText.getCleanText(), true);
mPersist.save();
}