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