1 /*
2  * Copyright (C) 2012 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.inputmethod.keyboard.internal;
18 
19 import android.content.res.TypedArray;
20 import android.graphics.Canvas;
21 import android.graphics.Paint;
22 import android.graphics.Paint.Align;
23 import android.graphics.Rect;
24 import android.graphics.RectF;
25 import android.text.TextUtils;
26 
27 import com.android.inputmethod.keyboard.PointerTracker;
28 import com.android.inputmethod.latin.R;
29 import com.android.inputmethod.latin.SuggestedWords;
30 import com.android.inputmethod.latin.common.CoordinateUtils;
31 
32 import javax.annotation.Nonnull;
33 
34 /**
35  * The class for single gesture preview text. The class for multiple gesture preview text will be
36  * derived from it.
37  *
38  * @attr ref R.styleable#KeyboardView_gestureFloatingPreviewTextSize
39  * @attr ref R.styleable#KeyboardView_gestureFloatingPreviewTextColor
40  * @attr ref R.styleable#KeyboardView_gestureFloatingPreviewTextOffset
41  * @attr ref R.styleable#KeyboardView_gestureFloatingPreviewColor
42  * @attr ref R.styleable#KeyboardView_gestureFloatingPreviewHorizontalPadding
43  * @attr ref R.styleable#KeyboardView_gestureFloatingPreviewVerticalPadding
44  * @attr ref R.styleable#KeyboardView_gestureFloatingPreviewRoundRadius
45  */
46 public class GestureFloatingTextDrawingPreview extends AbstractDrawingPreview {
47     protected static final class GesturePreviewTextParams {
48         public final int mGesturePreviewTextOffset;
49         public final int mGesturePreviewTextHeight;
50         public final float mGesturePreviewHorizontalPadding;
51         public final float mGesturePreviewVerticalPadding;
52         public final float mGesturePreviewRoundRadius;
53         public final int mDisplayWidth;
54 
55         private final int mGesturePreviewTextSize;
56         private final int mGesturePreviewTextColor;
57         private final int mGesturePreviewColor;
58         private final Paint mPaint = new Paint();
59 
60         private static final char[] TEXT_HEIGHT_REFERENCE_CHAR = { 'M' };
61 
GesturePreviewTextParams(final TypedArray mainKeyboardViewAttr)62         public GesturePreviewTextParams(final TypedArray mainKeyboardViewAttr) {
63             mGesturePreviewTextSize = mainKeyboardViewAttr.getDimensionPixelSize(
64                     R.styleable.MainKeyboardView_gestureFloatingPreviewTextSize, 0);
65             mGesturePreviewTextColor = mainKeyboardViewAttr.getColor(
66                     R.styleable.MainKeyboardView_gestureFloatingPreviewTextColor, 0);
67             mGesturePreviewTextOffset = mainKeyboardViewAttr.getDimensionPixelOffset(
68                     R.styleable.MainKeyboardView_gestureFloatingPreviewTextOffset, 0);
69             mGesturePreviewColor = mainKeyboardViewAttr.getColor(
70                     R.styleable.MainKeyboardView_gestureFloatingPreviewColor, 0);
71             mGesturePreviewHorizontalPadding = mainKeyboardViewAttr.getDimension(
72                     R.styleable.MainKeyboardView_gestureFloatingPreviewHorizontalPadding, 0.0f);
73             mGesturePreviewVerticalPadding = mainKeyboardViewAttr.getDimension(
74                     R.styleable.MainKeyboardView_gestureFloatingPreviewVerticalPadding, 0.0f);
75             mGesturePreviewRoundRadius = mainKeyboardViewAttr.getDimension(
76                     R.styleable.MainKeyboardView_gestureFloatingPreviewRoundRadius, 0.0f);
77             mDisplayWidth = mainKeyboardViewAttr.getResources().getDisplayMetrics().widthPixels;
78 
79             final Paint textPaint = getTextPaint();
80             final Rect textRect = new Rect();
81             textPaint.getTextBounds(TEXT_HEIGHT_REFERENCE_CHAR, 0, 1, textRect);
82             mGesturePreviewTextHeight = textRect.height();
83         }
84 
getTextPaint()85         public Paint getTextPaint() {
86             mPaint.setAntiAlias(true);
87             mPaint.setTextAlign(Align.CENTER);
88             mPaint.setTextSize(mGesturePreviewTextSize);
89             mPaint.setColor(mGesturePreviewTextColor);
90             return mPaint;
91         }
92 
getBackgroundPaint()93         public Paint getBackgroundPaint() {
94             mPaint.setColor(mGesturePreviewColor);
95             return mPaint;
96         }
97     }
98 
99     private final GesturePreviewTextParams mParams;
100     private final RectF mGesturePreviewRectangle = new RectF();
101     private int mPreviewTextX;
102     private int mPreviewTextY;
103     private SuggestedWords mSuggestedWords = SuggestedWords.getEmptyInstance();
104     private final int[] mLastPointerCoords = CoordinateUtils.newInstance();
105 
GestureFloatingTextDrawingPreview(final TypedArray mainKeyboardViewAttr)106     public GestureFloatingTextDrawingPreview(final TypedArray mainKeyboardViewAttr) {
107         mParams = new GesturePreviewTextParams(mainKeyboardViewAttr);
108     }
109 
110     @Override
onDeallocateMemory()111     public void onDeallocateMemory() {
112         // Nothing to do here.
113     }
114 
dismissGestureFloatingPreviewText()115     public void dismissGestureFloatingPreviewText() {
116         setSuggetedWords(SuggestedWords.getEmptyInstance());
117     }
118 
setSuggetedWords(@onnull final SuggestedWords suggestedWords)119     public void setSuggetedWords(@Nonnull final SuggestedWords suggestedWords) {
120         if (!isPreviewEnabled()) {
121             return;
122         }
123         mSuggestedWords = suggestedWords;
124         updatePreviewPosition();
125     }
126 
127     @Override
setPreviewPosition(final PointerTracker tracker)128     public void setPreviewPosition(final PointerTracker tracker) {
129         if (!isPreviewEnabled()) {
130             return;
131         }
132         tracker.getLastCoordinates(mLastPointerCoords);
133         updatePreviewPosition();
134     }
135 
136     /**
137      * Draws gesture preview text
138      * @param canvas The canvas where preview text is drawn.
139      */
140     @Override
drawPreview(final Canvas canvas)141     public void drawPreview(final Canvas canvas) {
142         if (!isPreviewEnabled() || mSuggestedWords.isEmpty()
143                 || TextUtils.isEmpty(mSuggestedWords.getWord(0))) {
144             return;
145         }
146         final float round = mParams.mGesturePreviewRoundRadius;
147         canvas.drawRoundRect(
148                 mGesturePreviewRectangle, round, round, mParams.getBackgroundPaint());
149         final String text = mSuggestedWords.getWord(0);
150         canvas.drawText(text, mPreviewTextX, mPreviewTextY, mParams.getTextPaint());
151     }
152 
153     /**
154      * Updates gesture preview text position based on mLastPointerCoords.
155      */
updatePreviewPosition()156     protected void updatePreviewPosition() {
157         if (mSuggestedWords.isEmpty() || TextUtils.isEmpty(mSuggestedWords.getWord(0))) {
158             invalidateDrawingView();
159             return;
160         }
161         final String text = mSuggestedWords.getWord(0);
162 
163         final RectF rectangle = mGesturePreviewRectangle;
164 
165         final int textHeight = mParams.mGesturePreviewTextHeight;
166         final float textWidth = mParams.getTextPaint().measureText(text);
167         final float hPad = mParams.mGesturePreviewHorizontalPadding;
168         final float vPad = mParams.mGesturePreviewVerticalPadding;
169         final float rectWidth = textWidth + hPad * 2.0f;
170         final float rectHeight = textHeight + vPad * 2.0f;
171 
172         final float rectX = Math.min(
173                 Math.max(CoordinateUtils.x(mLastPointerCoords) - rectWidth / 2.0f, 0.0f),
174                 mParams.mDisplayWidth - rectWidth);
175         final float rectY = CoordinateUtils.y(mLastPointerCoords)
176                 - mParams.mGesturePreviewTextOffset - rectHeight;
177         rectangle.set(rectX, rectY, rectX + rectWidth, rectY + rectHeight);
178 
179         mPreviewTextX = (int)(rectX + hPad + textWidth / 2.0f);
180         mPreviewTextY = (int)(rectY + vPad) + textHeight;
181         // TODO: Should narrow the invalidate region.
182         invalidateDrawingView();
183     }
184 }
185