ImageFloatingTextView.java revision 64aed1a21bfbf0ffbc75b20c67232174995e8803 
1/*
2 * Copyright (C) 2015 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
17package com.android.internal.widget;
18
19import android.annotation.Nullable;
20import android.content.Context;
21import android.text.BoringLayout;
22import android.text.Layout;
23import android.text.StaticLayout;
24import android.text.TextUtils;
25import android.util.AttributeSet;
26import android.view.RemotableViewMethod;
27import android.widget.RemoteViews;
28import android.widget.TextView;
29
30import com.android.internal.R;
31
32/**
33 * A TextView that can float around an image on the end.
34 *
35 * @hide
36 */
37@RemoteViews.RemoteView
38public class ImageFloatingTextView extends TextView {
39
40    /** Number of lines from the top to indent */
41    private int mIndentLines;
42
43    /** Resolved layout direction */
44    private int mResolvedDirection = LAYOUT_DIRECTION_UNDEFINED;
45    private int mMaxLinesForHeight = -1;
46    private boolean mFirstMeasure = true;
47    private int mLayoutMaxLines = -1;
48    private boolean mBlockLayouts;
49
50    public ImageFloatingTextView(Context context) {
51        this(context, null);
52    }
53
54    public ImageFloatingTextView(Context context, @Nullable AttributeSet attrs) {
55        this(context, attrs, 0);
56    }
57
58    public ImageFloatingTextView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
59        this(context, attrs, defStyleAttr, 0);
60    }
61
62    public ImageFloatingTextView(Context context, AttributeSet attrs, int defStyleAttr,
63            int defStyleRes) {
64        super(context, attrs, defStyleAttr, defStyleRes);
65    }
66
67    @Override
68    protected Layout makeSingleLayout(int wantWidth, BoringLayout.Metrics boring, int ellipsisWidth,
69            Layout.Alignment alignment, boolean shouldEllipsize,
70            TextUtils.TruncateAt effectiveEllipsize, boolean useSaved) {
71        CharSequence text = getText() == null ? "" : getText();
72        StaticLayout.Builder builder = StaticLayout.Builder.obtain(text, 0, text.length(),
73                getPaint(), wantWidth)
74                .setAlignment(alignment)
75                .setTextDirection(getTextDirectionHeuristic())
76                .setLineSpacing(getLineSpacingExtra(), getLineSpacingMultiplier())
77                .setIncludePad(getIncludeFontPadding())
78                .setBreakStrategy(Layout.BREAK_STRATEGY_HIGH_QUALITY)
79                .setHyphenationFrequency(Layout.HYPHENATION_FREQUENCY_FULL);
80        int maxLines;
81        if (mMaxLinesForHeight > 0) {
82            maxLines = mMaxLinesForHeight;
83        } else {
84            maxLines = getMaxLines() >= 0 ? getMaxLines() : Integer.MAX_VALUE;
85        }
86        builder.setMaxLines(maxLines);
87        mLayoutMaxLines = maxLines;
88        if (shouldEllipsize) {
89            builder.setEllipsize(effectiveEllipsize)
90                    .setEllipsizedWidth(ellipsisWidth);
91        }
92
93        // we set the endmargin on the requested number of lines.
94        int endMargin = getContext().getResources().getDimensionPixelSize(
95                R.dimen.notification_content_picture_margin);
96        int[] margins = null;
97        if (mIndentLines > 0) {
98            margins = new int[mIndentLines + 1];
99            for (int i = 0; i < mIndentLines; i++) {
100                margins[i] = endMargin;
101            }
102        }
103        if (mResolvedDirection == LAYOUT_DIRECTION_RTL) {
104            builder.setIndents(margins, null);
105        } else {
106            builder.setIndents(null, margins);
107        }
108
109        return builder.build();
110    }
111
112    @Override
113    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
114        int height = MeasureSpec.getSize(heightMeasureSpec);
115        // Lets calculate how many lines the given measurement allows us.
116        int availableHeight = height - mPaddingTop - mPaddingBottom;
117        int maxLines = availableHeight / getLineHeight();
118        if (getMaxLines() > 0) {
119            maxLines = Math.min(getMaxLines(), maxLines);
120        }
121        if (maxLines != mMaxLinesForHeight) {
122            mMaxLinesForHeight = maxLines;
123            if (getLayout() != null && mMaxLinesForHeight != mLayoutMaxLines) {
124                // Invalidate layout.
125                mBlockLayouts = true;
126                setHint(getHint());
127                mBlockLayouts = false;
128            }
129        }
130        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
131    }
132
133    @Override
134    public void requestLayout() {
135        if (!mBlockLayouts) {
136            super.requestLayout();
137        }
138    }
139
140    @Override
141    public void onRtlPropertiesChanged(int layoutDirection) {
142        super.onRtlPropertiesChanged(layoutDirection);
143
144        if (layoutDirection != mResolvedDirection && isLayoutDirectionResolved()) {
145            mResolvedDirection = layoutDirection;
146            if (mIndentLines > 0) {
147                // Invalidate layout.
148                setHint(getHint());
149            }
150        }
151    }
152
153    @RemotableViewMethod
154    public void setHasImage(boolean hasImage) {
155        setNumIndentLines(hasImage ? 2 : 0);
156    }
157
158    /**
159     * @param lines the number of lines at the top that should be indented by indentEnd
160     * @return whether a change was made
161     */
162    public boolean setNumIndentLines(int lines) {
163        if (mIndentLines != lines) {
164            mIndentLines = lines;
165            // Invalidate layout.
166            setHint(getHint());
167            return true;
168        }
169        return false;
170    }
171}
172