Java tutorial
/* * Copyright (c) 2013 Menny Even-Danan * * 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.yek.keyboard.keyboards.views; import android.content.Context; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.Paint.Align; import android.graphics.Rect; import android.graphics.Typeface; import android.graphics.drawable.Drawable; import android.support.annotation.NonNull; import android.support.v4.content.ContextCompat; import android.text.Layout.Alignment; import android.text.StaticLayout; import android.text.TextPaint; import android.text.TextUtils; import android.util.AttributeSet; import android.view.GestureDetector; import android.view.MotionEvent; import android.view.View; import com.yek.keyboard.anysoftkeyboard.AnySoftKeyboard; import com.yek.keyboard.theme.KeyboardTheme; import com.yek.keyboard.theme.KeyboardThemeFactory; import com.yek.keyboard.utils.Logger; import com.yek.keyboard.AnyApplication; import com.yek.keyboard.R; import java.util.ArrayList; import java.util.Arrays; import java.util.List; public class CandidateView extends View { private static final String TAG = "ASK CandidateView"; private static final int OUT_OF_BOUNDS_X_CORD = -1; private int mTouchX = OUT_OF_BOUNDS_X_CORD; private static final int MAX_SUGGESTIONS = 32; private final int[] mWordWidth = new int[MAX_SUGGESTIONS]; private final int[] mWordX = new int[MAX_SUGGESTIONS]; private static final int SCROLL_PIXELS = 20; private final ArrayList<CharSequence> mSuggestions = new ArrayList<>(); private final Drawable mSelectionHighlight; private final float mXGap; private final int mColorNormal; private final int mColorRecommended; private final int mColorOther; private final Paint mPaint; private final TextPaint mTextPaint; private final GestureDetector mGestureDetector; private AnySoftKeyboard mService; private boolean mNoticing = false; private boolean mShowingCompletions; private CharSequence mSelectedString; private CharSequence mJustAddedWord; private int mSelectedIndex; private boolean mTypedWordValid; private boolean mHaveMinimalSuggestion; private Rect mBgPadding; private Drawable mDivider; private boolean mScrolled; private boolean mShowingAddToDictionary; private CharSequence mAddToDictionaryHint; private int mTargetScrollX; private int mTotalWidth; public CandidateView(Context context, AttributeSet attrs) { this(context, attrs, 0); } /** * Construct a CandidateView for showing suggested words for completion. */ public CandidateView(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); mSelectionHighlight = ContextCompat.getDrawable(context, R.drawable.list_selector_background_pressed); mAddToDictionaryHint = context.getString(R.string.hint_add_to_dictionary); // themed final KeyboardTheme theme = KeyboardThemeFactory.getCurrentKeyboardTheme(context.getApplicationContext()); TypedArray a = theme.getPackageContext().obtainStyledAttributes(attrs, R.styleable.AnyKeyboardViewTheme, 0, theme.getThemeResId()); int colorNormal = ContextCompat.getColor(context, R.color.candidate_normal); int colorRecommended = ContextCompat.getColor(context, R.color.candidate_recommended); int colorOther = ContextCompat.getColor(context, R.color.candidate_other); float fontSizePixel = context.getResources().getDimensionPixelSize(R.dimen.candidate_font_height); try { colorNormal = a.getColor(R.styleable.AnyKeyboardViewTheme_suggestionNormalTextColor, colorNormal); colorRecommended = a.getColor(R.styleable.AnyKeyboardViewTheme_suggestionRecommendedTextColor, colorRecommended); colorOther = a.getColor(R.styleable.AnyKeyboardViewTheme_suggestionOthersTextColor, colorOther); mDivider = a.getDrawable(R.styleable.AnyKeyboardViewTheme_suggestionDividerImage); final Drawable stripImage = a.getDrawable(R.styleable.AnyKeyboardViewTheme_suggestionBackgroundImage); if (stripImage == null) setBackgroundColor(Color.BLACK); else setBackgroundDrawable(stripImage); fontSizePixel = a.getDimension(R.styleable.AnyKeyboardViewTheme_suggestionTextSize, fontSizePixel); } catch (Exception e) { Logger.w(TAG, "Got an exception while reading theme data", e); } mXGap = a.getDimension(R.styleable.AnyKeyboardViewTheme_suggestionWordXGap, 20); a.recycle(); mColorNormal = colorNormal; mColorRecommended = colorRecommended; mColorOther = colorOther; if (mDivider == null) mDivider = ContextCompat.getDrawable(context, R.drawable.dark_suggestions_divider); // end of themed mPaint = new Paint(); mPaint.setColor(mColorNormal); mPaint.setAntiAlias(true); mPaint.setTextSize(fontSizePixel); mPaint.setStrokeWidth(0); mPaint.setTextAlign(Align.CENTER); mTextPaint = new TextPaint(mPaint); final int minTouchableWidth = context.getResources() .getDimensionPixelOffset(R.dimen.candidate_min_touchable_width); mGestureDetector = new GestureDetector(context, new CandidateStripGestureListener(minTouchableWidth)); setWillNotDraw(false); setHorizontalScrollBarEnabled(false); setVerticalScrollBarEnabled(false); scrollTo(0, getScrollY()); } /** * A connection back to the service to communicate with the text field */ public void setService(AnySoftKeyboard listener) { mService = listener; } @Override public int computeHorizontalScrollRange() { return mTotalWidth; } /** * If the canvas is null, then only touch calculations are performed to pick * the target candidate. */ @Override protected void onDraw(Canvas canvas) { if (canvas != null) { super.onDraw(canvas); } mTotalWidth = 0; final int height = getHeight(); if (mBgPadding == null) { mBgPadding = new Rect(0, 0, 0, 0); if (getBackground() != null) { getBackground().getPadding(mBgPadding); } mDivider.setBounds(0, 0, mDivider.getIntrinsicWidth(), mDivider.getIntrinsicHeight()); } final int dividerYOffset = (height - mDivider.getMinimumHeight()) / 2; final int count = mSuggestions.size(); final Rect bgPadding = mBgPadding; final Paint paint = mPaint; final int touchX = mTouchX; final int scrollX = getScrollX(); final boolean scrolled = mScrolled; final boolean typedWordValid = mTypedWordValid; int x = 0; for (int i = 0; i < count; i++) { CharSequence suggestion = mSuggestions.get(i); if (suggestion == null) continue; final int wordLength = suggestion.length(); paint.setColor(mColorNormal); if (mHaveMinimalSuggestion && ((i == 1 && !typedWordValid) || (i == 0 && typedWordValid))) { paint.setTypeface(Typeface.DEFAULT_BOLD); paint.setColor(mColorRecommended); // existsAutoCompletion = true; } else if (i != 0 || (wordLength == 1 && count > 1)) { // HACK: even if i == 0, we use mColorOther when this // suggestion's length is 1 and // there are multiple suggestions, such as the default // punctuation list. paint.setColor(mColorOther); } // now that we set the typeFace, we can measure int wordWidth; if ((wordWidth = mWordWidth[i]) == 0) { float textWidth = paint.measureText(suggestion, 0, wordLength); // wordWidth = Math.max(0, (int) textWidth + X_GAP * 2); wordWidth = (int) (textWidth + mXGap * 2); mWordWidth[i] = wordWidth; } mWordX[i] = x; if (touchX != OUT_OF_BOUNDS_X_CORD && !scrolled && touchX + scrollX >= x && touchX + scrollX < x + wordWidth) { if (canvas != null && !mShowingAddToDictionary) { canvas.translate(x, 0); mSelectionHighlight.setBounds(0, bgPadding.top, wordWidth, height); mSelectionHighlight.draw(canvas); canvas.translate(-x, 0); } mSelectedString = suggestion; mSelectedIndex = i; } if (canvas != null) { // (+)This is the trick to get RTL/LTR text correct if (AnyApplication.getConfig().workaround_alwaysUseDrawText()) { final int y = (int) (height + paint.getTextSize() - paint.descent()) / 2; canvas.drawText(suggestion, 0, wordLength, x + wordWidth / 2, y, paint); } else { final int y = (int) (height - paint.getTextSize() + paint.descent()) / 2; // no matter what: StaticLayout float textX = x + (wordWidth / 2) - mXGap; float textY = y - bgPadding.bottom - bgPadding.top; canvas.translate(textX, textY); mTextPaint.setTypeface(paint.getTypeface()); mTextPaint.setColor(paint.getColor()); StaticLayout suggestionText = new StaticLayout(suggestion, mTextPaint, wordWidth, Alignment.ALIGN_CENTER, 1.0f, 0.0f, false); suggestionText.draw(canvas); canvas.translate(-textX, -textY); } // (-) paint.setColor(mColorOther); canvas.translate(x + wordWidth, 0); // Draw a divider unless it's after the hint //or the last suggested word if (count > 1 && (!mShowingAddToDictionary) && i != (count - 1)) { canvas.translate(0, dividerYOffset); mDivider.draw(canvas); canvas.translate(0, -dividerYOffset); } canvas.translate(-x - wordWidth, 0); } paint.setTypeface(Typeface.DEFAULT); x += wordWidth; } mTotalWidth = x; if (mTargetScrollX != scrollX) { scrollToTarget(); } } private void scrollToTarget() { int scrollX = getScrollX(); if (mTargetScrollX > scrollX) { scrollX += SCROLL_PIXELS; if (scrollX >= mTargetScrollX) { scrollX = mTargetScrollX; scrollTo(scrollX, getScrollY()); requestLayout(); } else { scrollTo(scrollX, getScrollY()); } } else { scrollX -= SCROLL_PIXELS; if (scrollX <= mTargetScrollX) { scrollX = mTargetScrollX; scrollTo(scrollX, getScrollY()); requestLayout(); } else { scrollTo(scrollX, getScrollY()); } } invalidate(); } /** * Setup what's to display in the suggestions strip * * @param suggestions the list of words to show * @param typedWordValid the typed word (word at index 0) is a valid word * @param haveMinimalSuggestion the list of suggestions contains a valid word. So, either * highlight the first word (typedWordValid == true), or * highlight the second word (typedWordValid != true) */ public void setSuggestions(List<CharSequence> suggestions, boolean completions, boolean typedWordValid, boolean haveMinimalSuggestion) { clear(); if (suggestions != null) { int insertCount = Math.min(suggestions.size(), MAX_SUGGESTIONS); for (CharSequence suggestion : suggestions) { mSuggestions.add(suggestion); if (--insertCount == 0) break; } } mShowingCompletions = completions; mTypedWordValid = typedWordValid; scrollTo(0, getScrollY()); mTargetScrollX = 0; mHaveMinimalSuggestion = haveMinimalSuggestion; //re-drawing required. invalidate(); } public void showAddToDictionaryHint(CharSequence word) { ArrayList<CharSequence> suggestions = new ArrayList<>(); suggestions.add(word); suggestions.add(mAddToDictionaryHint); setSuggestions(suggestions, false, false, false); mShowingAddToDictionary = true; } public boolean dismissAddToDictionaryHint() { if (!mShowingAddToDictionary) return false; clear(); return true; } /* package */List<CharSequence> getSuggestions() { return mSuggestions; } public void clear() { // Don't call mSuggestions.clear() because it's being used for logging // in LatinIME.pickSuggestionManually(). mSuggestions.clear(); mNoticing = false; mTouchX = OUT_OF_BOUNDS_X_CORD; mSelectedString = null; mSelectedIndex = -1; mShowingAddToDictionary = false; invalidate(); Arrays.fill(mWordWidth, 0); Arrays.fill(mWordX, 0); } @Override public boolean onTouchEvent(@NonNull MotionEvent me) { if (mGestureDetector.onTouchEvent(me)) { return true; } int action = me.getAction(); final int x = (int) me.getX(); final int y = (int) me.getY(); mTouchX = x; switch (action) { case MotionEvent.ACTION_DOWN: invalidate(); break; case MotionEvent.ACTION_MOVE: if (y <= 0) { // Fling up!? //Fling up should be a hacker's way to delete words (user dictionary words) if (mSelectedString != null) { Logger.d(TAG, "Fling up from candidates view. Deleting word at index %d, which is %s", mSelectedIndex, mSelectedString); mService.removeFromUserDictionary(mSelectedString.toString()); clear(); } } break; case MotionEvent.ACTION_UP: if (!mScrolled) { if (mSelectedString != null) { if (mShowingAddToDictionary) { final CharSequence word = mSuggestions.get(0); if (word.length() >= 2 && !mNoticing) { Logger.d(TAG, "User wants to add the word '%s' to the user-dictionary.", word); boolean added = mService.addWordToDictionary(word.toString()); if (!added) { Logger.w(TAG, "Failed to add word to user-dictionary!"); } } } else if (!mNoticing) { mService.pickSuggestionManually(mSelectedIndex, mSelectedString); } else if (mSelectedIndex == 1 && !TextUtils.isEmpty(mJustAddedWord)) { // 1 is the index of "Remove?" Logger.d(TAG, "User wants to remove an added word '%s'", mJustAddedWord); mService.removeFromUserDictionary(mJustAddedWord.toString()); } } } // hidePreview(); invalidate(); break; } return true; } public void notifyAboutWordAdded(CharSequence word) { mJustAddedWord = word; ArrayList<CharSequence> notice = new ArrayList<>(2); notice.add(getContext().getResources().getString(R.string.added_word, mJustAddedWord)); notice.add(getContext().getResources().getString(R.string.revert_added_word_question)); setSuggestions(notice, false, true, false); mNoticing = true; } public void notifyAboutRemovedWord(CharSequence word) { mJustAddedWord = null; ArrayList<CharSequence> notice = new ArrayList<>(1); notice.add(getContext().getResources().getString(R.string.removed_word, word)); setSuggestions(notice, false, true, false); mNoticing = true; } public void replaceTypedWord(CharSequence typedWord) { if (mSuggestions.size() > 0) { mSuggestions.set(0, typedWord); invalidate(); } } private class CandidateStripGestureListener extends GestureDetector.SimpleOnGestureListener { private final int mTouchSlopSquare; public CandidateStripGestureListener(int touchSlop) { // Slightly reluctant to scroll to be able to easily choose the // suggestion mTouchSlopSquare = touchSlop * touchSlop; } @Override public boolean onDown(MotionEvent e) { mScrolled = false; return false; } @Override public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) { if (!mScrolled) { // This is applied only when we recognize that scrolling is // starting. final int deltaX = (int) (e2.getX() - e1.getX()); final int deltaY = (int) (e2.getY() - e1.getY()); final int distance = (deltaX * deltaX) + (deltaY * deltaY); if (distance < mTouchSlopSquare) { return true; } mScrolled = true; } final int width = getWidth(); mScrolled = true; int scrollX = getScrollX(); scrollX += (int) distanceX; if (scrollX < 0) { scrollX = 0; } if (distanceX > 0 && scrollX + width > mTotalWidth) { scrollX -= (int) distanceX; } mTargetScrollX = scrollX; scrollTo(scrollX, getScrollY()); // hidePreview(); invalidate(); return true; } } }