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      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 
     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
     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
     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