1/*
2 * Copyright (C) 2010 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.gallery3d.ui;
18
19import android.graphics.Bitmap;
20import android.graphics.Canvas;
21import android.graphics.Color;
22import android.graphics.Paint.FontMetricsInt;
23import android.graphics.Typeface;
24import android.text.TextPaint;
25import android.text.TextUtils;
26import android.util.FloatMath;
27
28// StringTexture is a texture shows the content of a specified String.
29//
30// To create a StringTexture, use the newInstance() method and specify
31// the String, the font size, and the color.
32class StringTexture extends CanvasTexture {
33    private final String mText;
34    private final TextPaint mPaint;
35    private final FontMetricsInt mMetrics;
36
37    private StringTexture(String text, TextPaint paint,
38            FontMetricsInt metrics, int width, int height) {
39        super(width, height);
40        mText = text;
41        mPaint = paint;
42        mMetrics = metrics;
43    }
44
45    public static TextPaint getDefaultPaint(float textSize, int color) {
46        TextPaint paint = new TextPaint();
47        paint.setTextSize(textSize);
48        paint.setAntiAlias(true);
49        paint.setColor(color);
50        paint.setShadowLayer(2f, 0f, 0f, Color.BLACK);
51        return paint;
52    }
53
54    public static StringTexture newInstance(
55            String text, float textSize, int color) {
56        return newInstance(text, getDefaultPaint(textSize, color));
57    }
58
59    public static StringTexture newInstance(
60            String text, float textSize, int color,
61            float lengthLimit, boolean isBold) {
62        TextPaint paint = getDefaultPaint(textSize, color);
63        if (isBold) {
64            paint.setTypeface(Typeface.defaultFromStyle(Typeface.BOLD));
65        }
66        if (lengthLimit > 0) {
67            text = TextUtils.ellipsize(
68                    text, paint, lengthLimit, TextUtils.TruncateAt.END).toString();
69        }
70        return newInstance(text, paint);
71    }
72
73    private static StringTexture newInstance(String text, TextPaint paint) {
74        FontMetricsInt metrics = paint.getFontMetricsInt();
75        int width = (int) FloatMath.ceil(paint.measureText(text));
76        int height = metrics.bottom - metrics.top;
77        // The texture size needs to be at least 1x1.
78        if (width <= 0) width = 1;
79        if (height <= 0) height = 1;
80        return new StringTexture(text, paint, metrics, width, height);
81    }
82
83    @Override
84    protected void onDraw(Canvas canvas, Bitmap backing) {
85        canvas.translate(0, -mMetrics.ascent);
86        canvas.drawText(mText, 0, 0, mPaint);
87    }
88}
89