1 /*
2  * Copyright (C) 2014 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.phone.common.dialpad;
18 
19 import android.content.Context;
20 import android.graphics.Canvas;
21 import android.graphics.Paint;
22 import android.graphics.Rect;
23 import android.util.AttributeSet;
24 import android.widget.TextView;
25 
26 /**
27  * This is a custom text view intended only for rendering the numerals (and star and pound) on the
28  * dialpad. TextView has built in top/bottom padding to help account for ascenders/descenders.
29  *
30  * Since vertical space is at a premium on the dialpad, particularly if the font size is scaled to
31  * a larger default, for the dialpad we use this class to more precisely render characters according
32  * to the precise amount of space they need.
33  */
34 public class DialpadTextView extends TextView {
35     private Rect mTextBounds = new Rect();
36     private String mTextStr;
37 
DialpadTextView(Context context, AttributeSet attrs)38     public DialpadTextView(Context context, AttributeSet attrs) {
39         super(context, attrs);
40     }
41 
42     /**
43      * Draw the text to fit within the height/width which have been specified during measurement.
44      */
45     @Override
draw(Canvas canvas)46     public void draw(Canvas canvas) {
47         Paint paint = getPaint();
48 
49         // Without this, the draw does not respect the style's specified text color.
50         paint.setColor(getCurrentTextColor());
51 
52         // The text bounds values are relative and can be negative,, so rather than specifying a
53         // standard origin such as 0, 0, we need to use negative of the left/top bounds.
54         // For example, the bounds may be: Left: 11, Right: 37, Top: -77, Bottom: 0
55         canvas.drawText(mTextStr, -mTextBounds.left, -mTextBounds.top, paint);
56     }
57 
58     /**
59      * Calculate the pixel-accurate bounds of the text when rendered, and use that to specify the
60      * height and width.
61      */
62     @Override
onMeasure(int widthMeasureSpec, int heightMeasureSpec)63     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
64         super.onMeasure(widthMeasureSpec, heightMeasureSpec);
65         mTextStr = getText().toString();
66         getPaint().getTextBounds(mTextStr, 0, mTextStr.length(), mTextBounds);
67 
68         int width = resolveSize(mTextBounds.width(), widthMeasureSpec);
69         int height = resolveSize(mTextBounds.height(), heightMeasureSpec);
70         setMeasuredDimension(width, height);
71     }
72 }
73