| /* |
| * Copyright (C) 2016 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.calculator2; |
| |
| import android.annotation.TargetApi; |
| import android.content.ClipData; |
| import android.content.ClipDescription; |
| import android.content.ClipboardManager; |
| import android.content.Context; |
| import android.graphics.Rect; |
| import android.os.Build; |
| import android.support.annotation.IntDef; |
| import android.support.v4.content.ContextCompat; |
| import android.support.v4.os.BuildCompat; |
| import android.text.Layout; |
| import android.text.Spannable; |
| import android.text.SpannableString; |
| import android.text.Spanned; |
| import android.text.TextPaint; |
| import android.text.style.BackgroundColorSpan; |
| import android.text.style.ForegroundColorSpan; |
| import android.text.style.RelativeSizeSpan; |
| import android.util.AttributeSet; |
| import android.view.ActionMode; |
| import android.view.ContextMenu; |
| import android.view.GestureDetector; |
| import android.view.Menu; |
| import android.view.MenuInflater; |
| import android.view.MenuItem; |
| import android.view.MotionEvent; |
| import android.view.View; |
| import android.widget.OverScroller; |
| import android.widget.Toast; |
| |
| import java.lang.annotation.Retention; |
| import java.lang.annotation.RetentionPolicy; |
| |
| // A text widget that is "infinitely" scrollable to the right, |
| // and obtains the text to display via a callback to Logic. |
| public class CalculatorResult extends AlignedTextView implements MenuItem.OnMenuItemClickListener, |
| Evaluator.EvaluationListener, Evaluator.CharMetricsInfo { |
| static final int MAX_RIGHT_SCROLL = 10000000; |
| static final int INVALID = MAX_RIGHT_SCROLL + 10000; |
| // A larger value is unlikely to avoid running out of space |
| final OverScroller mScroller; |
| final GestureDetector mGestureDetector; |
| private long mIndex; // Index of expression we are displaying. |
| private Evaluator mEvaluator; |
| private boolean mScrollable = false; |
| // A scrollable result is currently displayed. |
| private boolean mValid = false; |
| // The result holds something valid; either a a number or an error |
| // message. |
| // A suffix of "Pos" denotes a pixel offset. Zero represents a scroll position |
| // in which the decimal point is just barely visible on the right of the display. |
| private int mCurrentPos;// Position of right of display relative to decimal point, in pixels. |
| // Large positive values mean the decimal point is scrolled off the |
| // left of the display. Zero means decimal point is barely displayed |
| // on the right. |
| private int mLastPos; // Position already reflected in display. Pixels. |
| private int mMinPos; // Minimum position to avoid unnecessary blanks on the left. Pixels. |
| private int mMaxPos; // Maximum position before we start displaying the infinite |
| // sequence of trailing zeroes on the right. Pixels. |
| private int mWholeLen; // Length of the whole part of current result. |
| // In the following, we use a suffix of Offset to denote a character position in a numeric |
| // string relative to the decimal point. Positive is to the right and negative is to |
| // the left. 1 = tenths position, -1 = units. Integer.MAX_VALUE is sometimes used |
| // for the offset of the last digit in an a nonterminating decimal expansion. |
| // We use the suffix "Index" to denote a zero-based index into a string representing a |
| // result. |
| private int mMaxCharOffset; // Character offset from decimal point of rightmost digit |
| // that should be displayed, plus the length of any exponent |
| // needed to display that digit. |
| // Limited to MAX_RIGHT_SCROLL. Often the same as: |
| private int mLsdOffset; // Position of least-significant digit in result |
| private int mLastDisplayedOffset; // Offset of last digit actually displayed after adding |
| // exponent. |
| private boolean mWholePartFits; // Scientific notation not needed for initial display. |
| private float mNoExponentCredit; |
| // Fraction of digit width saved by avoiding scientific notation. |
| // Only accessed from UI thread. |
| private boolean mAppendExponent; |
| // The result fits entirely in the display, even with an exponent, |
| // but not with grouping separators. Since the result is not |
| // scrollable, and we do not add the exponent to max. scroll position, |
| // append an exponent insteadd of replacing trailing digits. |
| private final Object mWidthLock = new Object(); |
| // Protects the next five fields. These fields are only |
| // Updated by the UI thread, and read accesses by the UI thread |
| // sometimes do not acquire the lock. |
| private int mWidthConstraint = 0; |
| // Our total width in pixels minus space for ellipsis. |
| // 0 ==> uninitialized. |
| private float mCharWidth = 1; |
| // Maximum character width. For now we pretend that all characters |
| // have this width. |
| // TODO: We're not really using a fixed width font. But it appears |
| // to be close enough for the characters we use that the difference |
| // is not noticeable. |
| private float mGroupingSeparatorWidthRatio; |
| // Fraction of digit width occupied by a digit separator. |
| private float mDecimalCredit; |
| // Fraction of digit width saved by replacing digit with decimal point. |
| private float mNoEllipsisCredit; |
| // Fraction of digit width saved by both replacing ellipsis with digit |
| // and avoiding scientific notation. |
| @Retention(RetentionPolicy.SOURCE) |
| @IntDef({SHOULD_REQUIRE, SHOULD_EVALUATE, SHOULD_NOT_EVALUATE}) |
| public @interface EvaluationRequest {} |
| public static final int SHOULD_REQUIRE = 2; |
| public static final int SHOULD_EVALUATE = 1; |
| public static final int SHOULD_NOT_EVALUATE = 0; |
| @EvaluationRequest private int mEvaluationRequest = SHOULD_REQUIRE; |
| // Should we evaluate when layout completes, and how? |
| private Evaluator.EvaluationListener mEvaluationListener = this; |
| // Listener to use if/when evaluation is requested. |
| public static final int MAX_LEADING_ZEROES = 6; |
| // Maximum number of leading zeroes after decimal point before we |
| // switch to scientific notation with negative exponent. |
| public static final int MAX_TRAILING_ZEROES = 6; |
| // Maximum number of trailing zeroes before the decimal point before |
| // we switch to scientific notation with positive exponent. |
| private static final int SCI_NOTATION_EXTRA = 1; |
| // Extra digits for standard scientific notation. In this case we |
| // have a decimal point and no ellipsis. |
| // We assume that we do not drop digits to make room for the decimal |
| // point in ordinary scientific notation. Thus >= 1. |
| private static final int MAX_COPY_EXTRA = 100; |
| // The number of extra digits we are willing to compute to copy |
| // a result as an exact number. |
| private static final int MAX_RECOMPUTE_DIGITS = 2000; |
| // The maximum number of digits we're willing to recompute in the UI |
| // thread. We only do this for known rational results, where we |
| // can bound the computation cost. |
| private final ForegroundColorSpan mExponentColorSpan; |
| private final BackgroundColorSpan mHighlightSpan; |
| |
| private ActionMode mActionMode; |
| private ActionMode.Callback mCopyActionModeCallback; |
| private ContextMenu mContextMenu; |
| |
| // The user requested that the result currently being evaluated should be stored to "memory". |
| private boolean mStoreToMemoryRequested = false; |
| |
| public CalculatorResult(Context context, AttributeSet attrs) { |
| super(context, attrs); |
| mScroller = new OverScroller(context); |
| mHighlightSpan = new BackgroundColorSpan(getHighlightColor()); |
| mExponentColorSpan = new ForegroundColorSpan( |
| ContextCompat.getColor(context, R.color.display_result_exponent_text_color)); |
| mGestureDetector = new GestureDetector(context, |
| new GestureDetector.SimpleOnGestureListener() { |
| @Override |
| public boolean onDown(MotionEvent e) { |
| return true; |
| } |
| @Override |
| public boolean onFling(MotionEvent e1, MotionEvent e2, |
| float velocityX, float velocityY) { |
| if (!mScroller.isFinished()) { |
| mCurrentPos = mScroller.getFinalX(); |
| } |
| mScroller.forceFinished(true); |
| stopActionModeOrContextMenu(); |
| CalculatorResult.this.cancelLongPress(); |
| // Ignore scrolls of error string, etc. |
| if (!mScrollable) return true; |
| mScroller.fling(mCurrentPos, 0, - (int) velocityX, 0 /* horizontal only */, |
| mMinPos, mMaxPos, 0, 0); |
| postInvalidateOnAnimation(); |
| return true; |
| } |
| @Override |
| public boolean onScroll(MotionEvent e1, MotionEvent e2, |
| float distanceX, float distanceY) { |
| int distance = (int)distanceX; |
| if (!mScroller.isFinished()) { |
| mCurrentPos = mScroller.getFinalX(); |
| } |
| mScroller.forceFinished(true); |
| stopActionModeOrContextMenu(); |
| CalculatorResult.this.cancelLongPress(); |
| if (!mScrollable) return true; |
| if (mCurrentPos + distance < mMinPos) { |
| distance = mMinPos - mCurrentPos; |
| } else if (mCurrentPos + distance > mMaxPos) { |
| distance = mMaxPos - mCurrentPos; |
| } |
| int duration = (int)(e2.getEventTime() - e1.getEventTime()); |
| if (duration < 1 || duration > 100) duration = 10; |
| mScroller.startScroll(mCurrentPos, 0, distance, 0, (int)duration); |
| postInvalidateOnAnimation(); |
| return true; |
| } |
| @Override |
| public void onLongPress(MotionEvent e) { |
| if (mValid) { |
| performLongClick(); |
| } |
| } |
| }); |
| setOnTouchListener(new View.OnTouchListener() { |
| @Override |
| public boolean onTouch(View v, MotionEvent event) { |
| return mGestureDetector.onTouchEvent(event); |
| } |
| }); |
| |
| if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) { |
| setupActionMode(); |
| } else { |
| setupContextMenu(); |
| } |
| |
| setCursorVisible(false); |
| setLongClickable(false); |
| setContentDescription(context.getString(R.string.desc_result)); |
| } |
| |
| void setEvaluator(Evaluator evaluator, long index) { |
| mEvaluator = evaluator; |
| mIndex = index; |
| requestLayout(); |
| } |
| |
| // Compute maximum digit width the hard way. |
| private static float getMaxDigitWidth(TextPaint paint) { |
| // Compute the maximum advance width for each digit, thus accounting for between-character |
| // spaces. If we ever support other kinds of digits, we may have to avoid kerning effects |
| // that could reduce the advance width within this particular string. |
| final String allDigits = "0123456789"; |
| final float[] widths = new float[allDigits.length()]; |
| paint.getTextWidths(allDigits, widths); |
| float maxWidth = 0; |
| for (float x : widths) { |
| maxWidth = Math.max(x, maxWidth); |
| } |
| return maxWidth; |
| } |
| |
| @Override |
| protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { |
| if (!isLaidOut()) { |
| // Set a minimum height so scaled error messages won't affect our layout. |
| setMinimumHeight(getLineHeight() + getCompoundPaddingBottom() |
| + getCompoundPaddingTop()); |
| } |
| |
| final TextPaint paint = getPaint(); |
| final Context context = getContext(); |
| final float newCharWidth = getMaxDigitWidth(paint); |
| // Digits are presumed to have no more than newCharWidth. |
| // There are two instances when we know that the result is otherwise narrower than |
| // expected: |
| // 1. For standard scientific notation (our type 1), we know that we have a norrow decimal |
| // point and no (usually wide) ellipsis symbol. We allow one extra digit |
| // (SCI_NOTATION_EXTRA) to compensate, and consider that in determining available width. |
| // 2. If we are using digit grouping separators and a decimal point, we give ourselves |
| // a fractional extra space for those separators, the value of which depends on whether |
| // there is also an ellipsis. |
| // |
| // Maximum extra space we need in various cases: |
| // Type 1 scientific notation, assuming ellipsis, minus sign and E are wider than a digit: |
| // Two minus signs + "E" + "." - 3 digits. |
| // Type 2 scientific notation: |
| // Ellipsis + "E" + "-" - 3 digits. |
| // In the absence of scientific notation, we may need a little less space. |
| // We give ourselves a bit of extra credit towards comma insertion and give |
| // ourselves more if we have either |
| // No ellipsis, or |
| // A decimal separator. |
| |
| // Calculate extra space we need to reserve, in addition to character count. |
| final float decimalSeparatorWidth = Layout.getDesiredWidth( |
| context.getString(R.string.dec_point), paint); |
| final float minusWidth = Layout.getDesiredWidth(context.getString(R.string.op_sub), paint); |
| final float minusExtraWidth = Math.max(minusWidth - newCharWidth, 0.0f); |
| final float ellipsisWidth = Layout.getDesiredWidth(KeyMaps.ELLIPSIS, paint); |
| final float ellipsisExtraWidth = Math.max(ellipsisWidth - newCharWidth, 0.0f); |
| final float expWidth = Layout.getDesiredWidth(KeyMaps.translateResult("e"), paint); |
| final float expExtraWidth = Math.max(expWidth - newCharWidth, 0.0f); |
| final float type1Extra = 2 * minusExtraWidth + expExtraWidth + decimalSeparatorWidth; |
| final float type2Extra = ellipsisExtraWidth + expExtraWidth + minusExtraWidth; |
| final float extraWidth = Math.max(type1Extra, type2Extra); |
| final int intExtraWidth = (int) Math.ceil(extraWidth) + 1 /* to cover rounding sins */; |
| final int newWidthConstraint = MeasureSpec.getSize(widthMeasureSpec) |
| - (getPaddingLeft() + getPaddingRight()) - intExtraWidth; |
| |
| // Calculate other width constants we need to handle grouping separators. |
| final float groupingSeparatorW = |
| Layout.getDesiredWidth(KeyMaps.translateResult(","), paint); |
| // Credits in the absence of any scientific notation: |
| float noExponentCredit = extraWidth - Math.max(ellipsisExtraWidth, minusExtraWidth); |
| final float noEllipsisCredit = extraWidth - minusExtraWidth; // includes noExponentCredit. |
| final float decimalCredit = Math.max(newCharWidth - decimalSeparatorWidth, 0.0f); |
| |
| mNoExponentCredit = noExponentCredit / newCharWidth; |
| synchronized(mWidthLock) { |
| mWidthConstraint = newWidthConstraint; |
| mCharWidth = newCharWidth; |
| mNoEllipsisCredit = noEllipsisCredit / newCharWidth; |
| mDecimalCredit = decimalCredit / newCharWidth; |
| mGroupingSeparatorWidthRatio = groupingSeparatorW / newCharWidth; |
| } |
| |
| super.onMeasure(widthMeasureSpec, heightMeasureSpec); |
| } |
| |
| @Override |
| protected void onLayout(boolean changed, int left, int top, int right, int bottom) { |
| super.onLayout(changed, left, top, right, bottom); |
| |
| if (mEvaluator != null && mEvaluationRequest != SHOULD_NOT_EVALUATE) { |
| final CalculatorExpr expr = mEvaluator.getExpr(mIndex); |
| if (expr != null && expr.hasInterestingOps()) { |
| if (mEvaluationRequest == SHOULD_REQUIRE) { |
| mEvaluator.requireResult(mIndex, mEvaluationListener, this); |
| } else { |
| mEvaluator.evaluateAndNotify(mIndex, mEvaluationListener, this); |
| } |
| } |
| } |
| } |
| |
| /** |
| * Specify whether we should evaluate result on layout. |
| * @param should one of SHOULD_REQUIRE, SHOULD_EVALUATE, SHOULD_NOT_EVALUATE |
| */ |
| public void setShouldEvaluateResult(@EvaluationRequest int request, |
| Evaluator.EvaluationListener listener) { |
| mEvaluationListener = listener; |
| mEvaluationRequest = request; |
| } |
| |
| // From Evaluator.CharMetricsInfo. |
| @Override |
| public float separatorChars(String s, int len) { |
| int start = 0; |
| while (start < len && !Character.isDigit(s.charAt(start))) { |
| ++start; |
| } |
| // We assume the rest consists of digits, and for consistency with the rest |
| // of the code, we assume all digits have width mCharWidth. |
| final int nDigits = len - start; |
| // We currently insert a digit separator every three digits. |
| final int nSeparators = (nDigits - 1) / 3; |
| synchronized(mWidthLock) { |
| // Always return an upper bound, even in the presence of rounding errors. |
| return nSeparators * mGroupingSeparatorWidthRatio; |
| } |
| } |
| |
| // From Evaluator.CharMetricsInfo. |
| @Override |
| public float getNoEllipsisCredit() { |
| synchronized(mWidthLock) { |
| return mNoEllipsisCredit; |
| } |
| } |
| |
| // From Evaluator.CharMetricsInfo. |
| @Override |
| public float getDecimalCredit() { |
| synchronized(mWidthLock) { |
| return mDecimalCredit; |
| } |
| } |
| |
| // Return the length of the exponent representation for the given exponent, in |
| // characters. |
| private final int expLen(int exp) { |
| if (exp == 0) return 0; |
| final int abs_exp_digits = (int) Math.ceil(Math.log10(Math.abs((double)exp)) |
| + 0.0000000001d /* Round whole numbers to next integer */); |
| return abs_exp_digits + (exp >= 0 ? 1 : 2); |
| } |
| |
| /** |
| * Initiate display of a new result. |
| * Only called from UI thread. |
| * The parameters specify various properties of the result. |
| * @param index Index of expression that was just evaluated. Currently ignored, since we only |
| * expect notification for the expression result being displayed. |
| * @param initPrec Initial display precision computed by evaluator. (1 = tenths digit) |
| * @param msd Position of most significant digit. Offset from left of string. |
| Evaluator.INVALID_MSD if unknown. |
| * @param leastDigPos Position of least significant digit (1 = tenths digit) |
| * or Integer.MAX_VALUE. |
| * @param truncatedWholePart Result up to but not including decimal point. |
| Currently we only use the length. |
| */ |
| @Override |
| public void onEvaluate(long index, int initPrec, int msd, int leastDigPos, |
| String truncatedWholePart) { |
| initPositions(initPrec, msd, leastDigPos, truncatedWholePart); |
| |
| if (mStoreToMemoryRequested) { |
| mEvaluator.copyToMemory(index); |
| mStoreToMemoryRequested = false; |
| } |
| redisplay(); |
| } |
| |
| /** |
| * Store the result for this index if it is available. |
| * If it is unavailable, set mStoreToMemoryRequested to indicate that we should store |
| * when evaluation is complete. |
| */ |
| public void onMemoryStore() { |
| if (mEvaluator.hasResult(mIndex)) { |
| mEvaluator.copyToMemory(mIndex); |
| } else { |
| mStoreToMemoryRequested = true; |
| mEvaluator.requireResult(mIndex, this /* listener */, this /* CharMetricsInfo */); |
| } |
| } |
| |
| /** |
| * Add the result to the value currently in memory. |
| */ |
| public void onMemoryAdd() { |
| mEvaluator.addToMemory(Evaluator.MAIN_INDEX); |
| } |
| |
| /** |
| * Subtract the result from the value currently in memory. |
| */ |
| public void onMemorySubtract() { |
| mEvaluator.subtractFromMemory(Evaluator.MAIN_INDEX); |
| } |
| |
| /** |
| * Set up scroll bounds (mMinPos, mMaxPos, etc.) and determine whether the result is |
| * scrollable, based on the supplied information about the result. |
| * This is unfortunately complicated because we need to predict whether trailing digits |
| * will eventually be replaced by an exponent. |
| * Just appending the exponent during formatting would be simpler, but would produce |
| * jumpier results during transitions. |
| * Only called from UI thread. |
| */ |
| private void initPositions(int initPrecOffset, int msdIndex, int lsdOffset, |
| String truncatedWholePart) { |
| int maxChars = getMaxChars(); |
| mWholeLen = truncatedWholePart.length(); |
| // Allow a tiny amount of slop for associativity/rounding differences in length |
| // calculation. If getPreferredPrec() decided it should fit, we want to make it fit, too. |
| // We reserved one extra pixel, so the extra length is OK. |
| final int nSeparatorChars = (int) Math.ceil( |
| separatorChars(truncatedWholePart, truncatedWholePart.length()) |
| - getNoEllipsisCredit() - 0.0001f); |
| mWholePartFits = mWholeLen + nSeparatorChars <= maxChars; |
| mLastPos = INVALID; |
| mLsdOffset = lsdOffset; |
| mAppendExponent = false; |
| // Prevent scrolling past initial position, which is calculated to show leading digits. |
| mCurrentPos = mMinPos = (int) Math.round(initPrecOffset * mCharWidth); |
| if (msdIndex == Evaluator.INVALID_MSD) { |
| // Possible zero value |
| if (lsdOffset == Integer.MIN_VALUE) { |
| // Definite zero value. |
| mMaxPos = mMinPos; |
| mMaxCharOffset = (int) Math.round(mMaxPos/mCharWidth); |
| mScrollable = false; |
| } else { |
| // May be very small nonzero value. Allow user to find out. |
| mMaxPos = mMaxCharOffset = MAX_RIGHT_SCROLL; |
| mMinPos -= mCharWidth; // Allow for future minus sign. |
| mScrollable = true; |
| } |
| return; |
| } |
| int negative = truncatedWholePart.charAt(0) == '-' ? 1 : 0; |
| if (msdIndex > mWholeLen && msdIndex <= mWholeLen + 3) { |
| // Avoid tiny negative exponent; pretend msdIndex is just to the right of decimal point. |
| msdIndex = mWholeLen - 1; |
| } |
| // Set to position of leftmost significant digit relative to dec. point. Usually negative. |
| int minCharOffset = msdIndex - mWholeLen; |
| if (minCharOffset > -1 && minCharOffset < MAX_LEADING_ZEROES + 2) { |
| // Small number of leading zeroes, avoid scientific notation. |
| minCharOffset = -1; |
| } |
| if (lsdOffset < MAX_RIGHT_SCROLL) { |
| mMaxCharOffset = lsdOffset; |
| if (mMaxCharOffset < -1 && mMaxCharOffset > -(MAX_TRAILING_ZEROES + 2)) { |
| mMaxCharOffset = -1; |
| } |
| // lsdOffset is positive or negative, never 0. |
| int currentExpLen = 0; // Length of required standard scientific notation exponent. |
| if (mMaxCharOffset < -1) { |
| currentExpLen = expLen(-minCharOffset - 1); |
| } else if (minCharOffset > -1 || mMaxCharOffset >= maxChars) { |
| // Number is either entirely to the right of decimal point, or decimal point is |
| // not visible when scrolled to the right. |
| currentExpLen = expLen(-minCharOffset); |
| } |
| // Exponent length does not included added decimal point. But whenever we add a |
| // decimal point, we allow an extra character (SCI_NOTATION_EXTRA). |
| final int separatorLength = mWholePartFits && minCharOffset < -3 ? nSeparatorChars : 0; |
| mScrollable = (mMaxCharOffset + currentExpLen + separatorLength - minCharOffset |
| + negative >= maxChars); |
| // Now adjust mMaxCharOffset for any required exponent. |
| int newMaxCharOffset; |
| if (currentExpLen > 0) { |
| if (mScrollable) { |
| // We'll use exponent corresponding to leastDigPos when scrolled to right. |
| newMaxCharOffset = mMaxCharOffset + expLen(-lsdOffset); |
| } else { |
| newMaxCharOffset = mMaxCharOffset + currentExpLen; |
| } |
| if (mMaxCharOffset <= -1 && newMaxCharOffset > -1) { |
| // Very unlikely; just drop exponent. |
| mMaxCharOffset = -1; |
| } else { |
| mMaxCharOffset = Math.min(newMaxCharOffset, MAX_RIGHT_SCROLL); |
| } |
| mMaxPos = Math.min((int) Math.round(mMaxCharOffset * mCharWidth), |
| MAX_RIGHT_SCROLL); |
| } else if (!mWholePartFits && !mScrollable) { |
| // Corner case in which entire number fits, but not with grouping separators. We |
| // will use an exponent in un-scrolled position, which may hide digits. Scrolling |
| // by one character will remove the exponent and reveal the last digits. Note |
| // that in the forced scientific notation case, the exponent length is not |
| // factored into mMaxCharOffset, since we do not want such an increase to impact |
| // scrolling behavior. In the unscrollable case, we thus have to append the |
| // exponent at the end using the forcePrecision argument to formatResult, in order |
| // to ensure that we get the entire result. |
| mScrollable = (mMaxCharOffset + expLen(-minCharOffset - 1) - minCharOffset |
| + negative >= maxChars); |
| if (mScrollable) { |
| mMaxPos = (int) Math.ceil(mMinPos + mCharWidth); |
| // Single character scroll will remove exponent and show remaining piece. |
| } else { |
| mMaxPos = mMinPos; |
| mAppendExponent = true; |
| } |
| } else { |
| mMaxPos = Math.min((int) Math.round(mMaxCharOffset * mCharWidth), |
| MAX_RIGHT_SCROLL); |
| } |
| if (!mScrollable) { |
| // Position the number consistently with our assumptions to make sure it |
| // actually fits. |
| mCurrentPos = mMaxPos; |
| } |
| } else { |
| mMaxPos = mMaxCharOffset = MAX_RIGHT_SCROLL; |
| mScrollable = true; |
| } |
| } |
| |
| /** |
| * Display error message indicated by resourceId. |
| * UI thread only. |
| */ |
| @Override |
| public void onError(long index, int resourceId) { |
| mStoreToMemoryRequested = false; |
| mValid = true; |
| setLongClickable(false); |
| mScrollable = false; |
| final String msg = getContext().getString(resourceId); |
| final float measuredWidth = Layout.getDesiredWidth(msg, getPaint()); |
| if (measuredWidth > mWidthConstraint) { |
| // Multiply by .99 to avoid rounding effects. |
| final float scaleFactor = 0.99f * mWidthConstraint / measuredWidth; |
| final RelativeSizeSpan smallTextSpan = new RelativeSizeSpan(scaleFactor); |
| final SpannableString scaledMsg = new SpannableString(msg); |
| scaledMsg.setSpan(smallTextSpan, 0, msg.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE); |
| setText(scaledMsg); |
| } else { |
| setText(msg); |
| } |
| } |
| |
| private final int MAX_COPY_SIZE = 1000000; |
| |
| /* |
| * Return the most significant digit position in the given string or Evaluator.INVALID_MSD. |
| * Unlike Evaluator.getMsdIndexOf, we treat a final 1 as significant. |
| * Pure function; callable from anywhere. |
| */ |
| public static int getNaiveMsdIndexOf(String s) { |
| final int len = s.length(); |
| for (int i = 0; i < len; ++i) { |
| char c = s.charAt(i); |
| if (c != '-' && c != '.' && c != '0') { |
| return i; |
| } |
| } |
| return Evaluator.INVALID_MSD; |
| } |
| |
| /** |
| * Format a result returned by Evaluator.getString() into a single line containing ellipses |
| * (if appropriate) and an exponent (if appropriate). |
| * We add two distinct kinds of exponents: |
| * (1) If the final result contains the leading digit we use standard scientific notation. |
| * (2) If not, we add an exponent corresponding to an interpretation of the final result as |
| * an integer. |
| * We add an ellipsis on the left if the result was truncated. |
| * We add ellipses and exponents in a way that leaves most digits in the position they |
| * would have been in had we not done so. This minimizes jumps as a result of scrolling. |
| * Result is NOT internationalized, uses "E" for exponent. |
| * Called only from UI thread; We sometimes omit locking for fields. |
| * @param precOffset The value that was passed to getString. Identifies the significance of |
| the rightmost digit. A value of 1 means the rightmost digits corresponds to tenths. |
| * @param maxDigs The maximum number of characters in the result |
| * @param truncated The in parameter was already truncated, beyond possibly removing the |
| minus sign. |
| * @param negative The in parameter represents a negative result. (Minus sign may be removed |
| without setting truncated.) |
| * @param lastDisplayedOffset If not null, we set lastDisplayedOffset[0] to the offset of |
| the last digit actually appearing in the display. |
| * @param forcePrecision If true, we make sure that the last displayed digit corresponds to |
| precOffset, and allow maxDigs to be exceeded in adding the exponent and commas. |
| * @param forceSciNotation Force scientific notation. May be set because we don't have |
| space for grouping separators, but whole number otherwise fits. |
| * @param insertCommas Insert commas (literally, not internationalized) as digit separators. |
| We only ever do this for the integral part of a number, and only when no |
| exponent is displayed in the initial position. The combination of which means |
| that we only do it when no exponent is displayed. |
| We insert commas in a way that does consider the width of the actual localized digit |
| separator. Commas count towards maxDigs as the appropriate fraction of a digit. |
| */ |
| private String formatResult(String in, int precOffset, int maxDigs, boolean truncated, |
| boolean negative, int lastDisplayedOffset[], boolean forcePrecision, |
| boolean forceSciNotation, boolean insertCommas) { |
| final int minusSpace = negative ? 1 : 0; |
| final int msdIndex = truncated ? -1 : getNaiveMsdIndexOf(in); // INVALID_MSD is OK. |
| String result = in; |
| boolean needEllipsis = false; |
| if (truncated || (negative && result.charAt(0) != '-')) { |
| needEllipsis = true; |
| result = KeyMaps.ELLIPSIS + result.substring(1, result.length()); |
| // Ellipsis may be removed again in the type(1) scientific notation case. |
| } |
| final int decIndex = result.indexOf('.'); |
| if (lastDisplayedOffset != null) { |
| lastDisplayedOffset[0] = precOffset; |
| } |
| if (forceSciNotation || (decIndex == -1 || msdIndex != Evaluator.INVALID_MSD |
| && msdIndex - decIndex > MAX_LEADING_ZEROES + 1) && precOffset != -1) { |
| // Either: |
| // 1) No decimal point displayed, and it's not just to the right of the last digit, or |
| // 2) we are at the front of a number whos integral part is too large to allow |
| // comma insertion, or |
| // 3) we should suppress leading zeroes. |
| // Add an exponent to let the user track which digits are currently displayed. |
| // Start with type (2) exponent if we dropped no digits. -1 accounts for decimal point. |
| // We currently never show digit separators together with an exponent. |
| final int initExponent = precOffset > 0 ? -precOffset : -precOffset - 1; |
| int exponent = initExponent; |
| boolean hasPoint = false; |
| if (!truncated && msdIndex < maxDigs - 1 |
| && result.length() - msdIndex + 1 + minusSpace |
| <= maxDigs + SCI_NOTATION_EXTRA) { |
| // Type (1) exponent computation and transformation: |
| // Leading digit is in display window. Use standard calculator scientific notation |
| // with one digit to the left of the decimal point. Insert decimal point and |
| // delete leading zeroes. |
| // We try to keep leading digits roughly in position, and never |
| // lengthen the result by more than SCI_NOTATION_EXTRA. |
| if (decIndex > msdIndex) { |
| // In the forceSciNotation, we can have a decimal point in the relevant digit |
| // range. Remove it. |
| result = result.substring(0, decIndex) |
| + result.substring(decIndex + 1, result.length()); |
| // msdIndex and precOffset unaffected. |
| } |
| final int resLen = result.length(); |
| String fraction = result.substring(msdIndex + 1, resLen); |
| result = (negative ? "-" : "") + result.substring(msdIndex, msdIndex + 1) |
| + "." + fraction; |
| // Original exp was correct for decimal point at right of fraction. |
| // Adjust by length of fraction. |
| exponent = initExponent + resLen - msdIndex - 1; |
| hasPoint = true; |
| } |
| // Exponent can't be zero. |
| // Actually add the exponent of either type: |
| if (!forcePrecision) { |
| int dropDigits; // Digits to drop to make room for exponent. |
| if (hasPoint) { |
| // Type (1) exponent. |
| // Drop digits even if there is room. Otherwise the scrolling gets jumpy. |
| dropDigits = expLen(exponent); |
| if (dropDigits >= result.length() - 1) { |
| // Jumpy is better than no mantissa. Probably impossible anyway. |
| dropDigits = Math.max(result.length() - 2, 0); |
| } |
| } else { |
| // Type (2) exponent. |
| // Exponent depends on the number of digits we drop, which depends on |
| // exponent ... |
| for (dropDigits = 2; expLen(initExponent + dropDigits) > dropDigits; |
| ++dropDigits) {} |
| exponent = initExponent + dropDigits; |
| if (precOffset - dropDigits > mLsdOffset) { |
| // This can happen if e.g. result = 10^40 + 10^10 |
| // It turns out we would otherwise display ...10e9 because it takes |
| // the same amount of space as ...1e10 but shows one more digit. |
| // But we don't want to display a trailing zero, even if it's free. |
| ++dropDigits; |
| ++exponent; |
| } |
| } |
| result = result.substring(0, result.length() - dropDigits); |
| if (lastDisplayedOffset != null) { |
| lastDisplayedOffset[0] -= dropDigits; |
| } |
| } |
| result = result + "E" + Integer.toString(exponent); |
| } else if (insertCommas) { |
| // Add commas to the whole number section, and then truncate on left to fit, |
| // counting commas as a fractional digit. |
| final int wholeStart = needEllipsis ? 1 : 0; |
| int orig_length = result.length(); |
| final float nCommaChars; |
| if (decIndex != -1) { |
| nCommaChars = separatorChars(result, decIndex); |
| result = StringUtils.addCommas(result, wholeStart, decIndex) |
| + result.substring(decIndex, orig_length); |
| } else { |
| nCommaChars = separatorChars(result, orig_length); |
| result = StringUtils.addCommas(result, wholeStart, orig_length); |
| } |
| if (needEllipsis) { |
| orig_length -= 1; // Exclude ellipsis. |
| } |
| final float len = orig_length + nCommaChars; |
| int deletedChars = 0; |
| final float ellipsisCredit = getNoEllipsisCredit(); |
| final float decimalCredit = getDecimalCredit(); |
| final float effectiveLen = len - (decIndex == -1 ? 0 : getDecimalCredit()); |
| final float ellipsisAdjustment = |
| needEllipsis ? mNoExponentCredit : getNoEllipsisCredit(); |
| // As above, we allow for a tiny amount of extra length here, for consistency with |
| // getPreferredPrec(). |
| if (effectiveLen - ellipsisAdjustment > (float) (maxDigs - wholeStart) + 0.0001f |
| && !forcePrecision) { |
| float deletedWidth = 0.0f; |
| while (effectiveLen - mNoExponentCredit - deletedWidth |
| > (float) (maxDigs - 1 /* for ellipsis */)) { |
| if (result.charAt(deletedChars) == ',') { |
| deletedWidth += mGroupingSeparatorWidthRatio; |
| } else { |
| deletedWidth += 1.0f; |
| } |
| deletedChars++; |
| } |
| } |
| if (deletedChars > 0) { |
| result = KeyMaps.ELLIPSIS + result.substring(deletedChars, result.length()); |
| } else if (needEllipsis) { |
| result = KeyMaps.ELLIPSIS + result; |
| } |
| } |
| return result; |
| } |
| |
| /** |
| * Get formatted, but not internationalized, result from mEvaluator. |
| * @param precOffset requested position (1 = tenths) of last included digit |
| * @param maxSize maximum number of characters (more or less) in result |
| * @param lastDisplayedOffset zeroth entry is set to actual offset of last included digit, |
| * after adjusting for exponent, etc. May be null. |
| * @param forcePrecision Ensure that last included digit is at pos, at the expense |
| * of treating maxSize as a soft limit. |
| * @param forceSciNotation Force scientific notation, even if not required by maxSize. |
| * @param insertCommas Insert commas as digit separators. |
| */ |
| private String getFormattedResult(int precOffset, int maxSize, int lastDisplayedOffset[], |
| boolean forcePrecision, boolean forceSciNotation, boolean insertCommas) { |
| final boolean truncated[] = new boolean[1]; |
| final boolean negative[] = new boolean[1]; |
| final int requestedPrecOffset[] = {precOffset}; |
| final String rawResult = mEvaluator.getString(mIndex, requestedPrecOffset, mMaxCharOffset, |
| maxSize, truncated, negative, this); |
| return formatResult(rawResult, requestedPrecOffset[0], maxSize, truncated[0], negative[0], |
| lastDisplayedOffset, forcePrecision, forceSciNotation, insertCommas); |
| } |
| |
| /** |
| * Return entire result (within reason) up to current displayed precision. |
| * @param withSeparators Add digit separators |
| */ |
| public String getFullText(boolean withSeparators) { |
| if (!mValid) return ""; |
| if (!mScrollable) return getText().toString(); |
| return KeyMaps.translateResult(getFormattedResult(mLastDisplayedOffset, MAX_COPY_SIZE, |
| null, true /* forcePrecision */, false /* forceSciNotation */, withSeparators)); |
| } |
| |
| /** |
| * Did the above produce a correct result? |
| * UI thread only. |
| */ |
| public boolean fullTextIsExact() { |
| return !mScrollable || (mMaxCharOffset == getCharOffset(mCurrentPos) |
| && mMaxCharOffset != MAX_RIGHT_SCROLL); |
| } |
| |
| /** |
| * Get entire result up to current displayed precision, or up to MAX_COPY_EXTRA additional |
| * digits, if it will lead to an exact result. |
| */ |
| public String getFullCopyText() { |
| if (!mValid |
| || mLsdOffset == Integer.MAX_VALUE |
| || fullTextIsExact() |
| || mWholeLen > MAX_RECOMPUTE_DIGITS |
| || mWholeLen + mLsdOffset > MAX_RECOMPUTE_DIGITS |
| || mLsdOffset - mLastDisplayedOffset > MAX_COPY_EXTRA) { |
| return getFullText(false /* withSeparators */); |
| } |
| // It's reasonable to compute and copy the exact result instead. |
| final int nonNegLsdOffset = Math.max(0, mLsdOffset); |
| final String rawResult = mEvaluator.getResult(mIndex).toStringTruncated(nonNegLsdOffset); |
| final String formattedResult = formatResult(rawResult, nonNegLsdOffset, MAX_COPY_SIZE, |
| false, rawResult.charAt(0) == '-', null, true /* forcePrecision */, |
| false /* forceSciNotation */, false /* insertCommas */); |
| return KeyMaps.translateResult(formattedResult); |
| } |
| |
| /** |
| * Return the maximum number of characters that will fit in the result display. |
| * May be called asynchronously from non-UI thread. From Evaluator.CharMetricsInfo. |
| * Returns zero if measurement hasn't completed. |
| */ |
| @Override |
| public int getMaxChars() { |
| int result; |
| synchronized(mWidthLock) { |
| return (int) Math.floor(mWidthConstraint / mCharWidth); |
| } |
| } |
| |
| /** |
| * @return {@code true} if the currently displayed result is scrollable |
| */ |
| public boolean isScrollable() { |
| return mScrollable; |
| } |
| |
| /** |
| * Map pixel position to digit offset. |
| * UI thread only. |
| */ |
| int getCharOffset(int pos) { |
| return (int) Math.round(pos / mCharWidth); // Lock not needed. |
| } |
| |
| void clear() { |
| mValid = false; |
| mScrollable = false; |
| setText(""); |
| setLongClickable(false); |
| } |
| |
| @Override |
| public void onCancelled(long index) { |
| clear(); |
| mStoreToMemoryRequested = false; |
| } |
| |
| /** |
| * Refresh display. |
| * Only called in UI thread. Index argument is currently ignored. |
| */ |
| @Override |
| public void onReevaluate(long index) { |
| redisplay(); |
| } |
| |
| public void redisplay() { |
| if (mScroller.isFinished() && length() > 0) { |
| setAccessibilityLiveRegion(ACCESSIBILITY_LIVE_REGION_POLITE); |
| } |
| int currentCharOffset = getCharOffset(mCurrentPos); |
| int maxChars = getMaxChars(); |
| int lastDisplayedOffset[] = new int[1]; |
| String result = getFormattedResult(currentCharOffset, maxChars, lastDisplayedOffset, |
| mAppendExponent /* forcePrecision; preserve entire result */, |
| !mWholePartFits |
| && currentCharOffset == getCharOffset(mMinPos) /* forceSciNotation */, |
| mWholePartFits /* insertCommas */ ); |
| int expIndex = result.indexOf('E'); |
| result = KeyMaps.translateResult(result); |
| if (expIndex > 0 && result.indexOf('.') == -1) { |
| // Gray out exponent if used as position indicator |
| SpannableString formattedResult = new SpannableString(result); |
| formattedResult.setSpan(mExponentColorSpan, expIndex, result.length(), |
| Spanned.SPAN_EXCLUSIVE_EXCLUSIVE); |
| setText(formattedResult); |
| } else { |
| setText(result); |
| } |
| mLastDisplayedOffset = lastDisplayedOffset[0]; |
| mValid = true; |
| setLongClickable(true); |
| } |
| |
| @Override |
| protected void onTextChanged(java.lang.CharSequence text, int start, int lengthBefore, |
| int lengthAfter) { |
| super.onTextChanged(text, start, lengthBefore, lengthAfter); |
| |
| if (!mScrollable || mScroller.isFinished()) { |
| if (lengthBefore == 0 && lengthAfter > 0) { |
| setAccessibilityLiveRegion(ACCESSIBILITY_LIVE_REGION_POLITE); |
| setContentDescription(null); |
| } else if (lengthBefore > 0 && lengthAfter == 0) { |
| setAccessibilityLiveRegion(ACCESSIBILITY_LIVE_REGION_NONE); |
| setContentDescription(getContext().getString(R.string.desc_result)); |
| } |
| } |
| } |
| |
| @Override |
| public void computeScroll() { |
| if (!mScrollable) { |
| return; |
| } |
| |
| if (mScroller.computeScrollOffset()) { |
| mCurrentPos = mScroller.getCurrX(); |
| if (getCharOffset(mCurrentPos) != getCharOffset(mLastPos)) { |
| mLastPos = mCurrentPos; |
| redisplay(); |
| } |
| } |
| |
| if (!mScroller.isFinished()) { |
| postInvalidateOnAnimation(); |
| setAccessibilityLiveRegion(ACCESSIBILITY_LIVE_REGION_NONE); |
| } else if (length() > 0){ |
| setAccessibilityLiveRegion(ACCESSIBILITY_LIVE_REGION_POLITE); |
| } |
| } |
| |
| /** |
| * Use ActionMode for copy/memory support on M and higher. |
| */ |
| @TargetApi(Build.VERSION_CODES.M) |
| private void setupActionMode() { |
| mCopyActionModeCallback = new ActionMode.Callback2() { |
| |
| @Override |
| public boolean onCreateActionMode(ActionMode mode, Menu menu) { |
| final MenuInflater inflater = mode.getMenuInflater(); |
| return createCopyMenu(inflater, menu); |
| } |
| |
| @Override |
| public boolean onPrepareActionMode(ActionMode mode, Menu menu) { |
| return false; // Return false if nothing is done |
| } |
| |
| @Override |
| public boolean onActionItemClicked(ActionMode mode, MenuItem item) { |
| if (onMenuItemClick(item)) { |
| mode.finish(); |
| return true; |
| } else { |
| return false; |
| } |
| } |
| |
| @Override |
| public void onDestroyActionMode(ActionMode mode) { |
| unhighlightResult(); |
| mActionMode = null; |
| } |
| |
| @Override |
| public void onGetContentRect(ActionMode mode, View view, Rect outRect) { |
| super.onGetContentRect(mode, view, outRect); |
| |
| outRect.left += view.getPaddingLeft(); |
| outRect.top += view.getPaddingTop(); |
| outRect.right -= view.getPaddingRight(); |
| outRect.bottom -= view.getPaddingBottom(); |
| final int width = (int) Layout.getDesiredWidth(getText(), getPaint()); |
| if (width < outRect.width()) { |
| outRect.left = outRect.right - width; |
| } |
| |
| if (!BuildCompat.isAtLeastN()) { |
| // The CAB (prior to N) only takes the translation of a view into account, so |
| // if a scale is applied to the view then the offset outRect will end up being |
| // positioned incorrectly. We workaround that limitation by manually applying |
| // the scale to the outRect, which the CAB will then offset to the correct |
| // position. |
| final float scaleX = view.getScaleX(); |
| final float scaleY = view.getScaleY(); |
| outRect.left *= scaleX; |
| outRect.right *= scaleX; |
| outRect.top *= scaleY; |
| outRect.bottom *= scaleY; |
| } |
| } |
| }; |
| setOnLongClickListener(new View.OnLongClickListener() { |
| @Override |
| public boolean onLongClick(View v) { |
| if (mValid) { |
| mActionMode = startActionMode(mCopyActionModeCallback, |
| ActionMode.TYPE_FLOATING); |
| return true; |
| } |
| return false; |
| } |
| }); |
| } |
| |
| /** |
| * Use ContextMenu for copy/memory support on L and lower. |
| */ |
| private void setupContextMenu() { |
| setOnCreateContextMenuListener(new OnCreateContextMenuListener() { |
| @Override |
| public void onCreateContextMenu(ContextMenu contextMenu, View view, |
| ContextMenu.ContextMenuInfo contextMenuInfo) { |
| final MenuInflater inflater = new MenuInflater(getContext()); |
| createCopyMenu(inflater, contextMenu); |
| mContextMenu = contextMenu; |
| for(int i = 0; i < contextMenu.size(); i ++) { |
| contextMenu.getItem(i).setOnMenuItemClickListener(CalculatorResult.this); |
| } |
| } |
| }); |
| setOnLongClickListener(new View.OnLongClickListener() { |
| @Override |
| public boolean onLongClick(View v) { |
| if (mValid) { |
| return showContextMenu(); |
| } |
| return false; |
| } |
| }); |
| } |
| |
| private boolean createCopyMenu(MenuInflater inflater, Menu menu) { |
| inflater.inflate(R.menu.menu_result, menu); |
| final boolean displayMemory = mEvaluator.getMemoryIndex() != 0; |
| final MenuItem memoryAddItem = menu.findItem(R.id.memory_add); |
| final MenuItem memorySubtractItem = menu.findItem(R.id.memory_subtract); |
| memoryAddItem.setEnabled(displayMemory); |
| memorySubtractItem.setEnabled(displayMemory); |
| highlightResult(); |
| return true; |
| } |
| |
| public boolean stopActionModeOrContextMenu() { |
| if (mActionMode != null) { |
| mActionMode.finish(); |
| return true; |
| } |
| if (mContextMenu != null) { |
| unhighlightResult(); |
| mContextMenu.close(); |
| return true; |
| } |
| return false; |
| } |
| |
| private void highlightResult() { |
| final Spannable text = (Spannable) getText(); |
| text.setSpan(mHighlightSpan, 0, text.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE); |
| } |
| |
| private void unhighlightResult() { |
| final Spannable text = (Spannable) getText(); |
| text.removeSpan(mHighlightSpan); |
| } |
| |
| private void setPrimaryClip(ClipData clip) { |
| ClipboardManager clipboard = (ClipboardManager) getContext(). |
| getSystemService(Context.CLIPBOARD_SERVICE); |
| clipboard.setPrimaryClip(clip); |
| } |
| |
| private void copyContent() { |
| final CharSequence text = getFullCopyText(); |
| ClipboardManager clipboard = |
| (ClipboardManager) getContext().getSystemService(Context.CLIPBOARD_SERVICE); |
| // We include a tag URI, to allow us to recognize our own results and handle them |
| // specially. |
| ClipData.Item newItem = new ClipData.Item(text, null, mEvaluator.capture(mIndex)); |
| String[] mimeTypes = new String[] {ClipDescription.MIMETYPE_TEXT_PLAIN}; |
| ClipData cd = new ClipData("calculator result", mimeTypes, newItem); |
| clipboard.setPrimaryClip(cd); |
| Toast.makeText(getContext(), R.string.text_copied_toast, Toast.LENGTH_SHORT).show(); |
| } |
| |
| @Override |
| public boolean onMenuItemClick(MenuItem item) { |
| switch (item.getItemId()) { |
| case R.id.memory_add: |
| onMemoryAdd(); |
| return true; |
| case R.id.memory_subtract: |
| onMemorySubtract(); |
| return true; |
| case R.id.memory_store: |
| onMemoryStore(); |
| return true; |
| case R.id.menu_copy: |
| if (mEvaluator.evaluationInProgress(mIndex)) { |
| // Refuse to copy placeholder characters. |
| return false; |
| } else { |
| copyContent(); |
| unhighlightResult(); |
| return true; |
| } |
| default: |
| return false; |
| } |
| } |
| } |