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 17 package com.android.calculator2; 18 19 import android.content.Context; 20 import android.graphics.Paint; 21 import android.graphics.Rect; 22 import android.util.AttributeSet; 23 import android.widget.TextView; 24 25 /** 26 * Extended {@link TextView} that supports ascent/baseline alignment. 27 */ 28 public class AlignedTextView extends TextView { 29 30 private static final String LATIN_CAPITAL_LETTER = "H"; 31 32 // temporary rect for use during layout 33 private final Rect mTempRect = new Rect(); 34 35 private int mTopPaddingOffset; 36 private int mBottomPaddingOffset; 37 38 public AlignedTextView(Context context) { 39 this(context, null /* attrs */); 40 } 41 42 public AlignedTextView(Context context, AttributeSet attrs) { 43 this(context, attrs, android.R.attr.textViewStyle); 44 } 45 46 public AlignedTextView(Context context, AttributeSet attrs, int defStyleAttr) { 47 super(context, attrs, defStyleAttr); 48 49 // Disable any included font padding by default. 50 setIncludeFontPadding(false); 51 } 52 53 @Override 54 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 55 final Paint paint = getPaint(); 56 57 // Always align text to the default capital letter height. 58 paint.getTextBounds(LATIN_CAPITAL_LETTER, 0, 1, mTempRect); 59 60 mTopPaddingOffset = Math.min(getPaddingTop(), 61 (int) Math.ceil(mTempRect.top - paint.ascent())); 62 mBottomPaddingOffset = Math.min(getPaddingBottom(), (int) Math.ceil(paint.descent())); 63 64 super.onMeasure(widthMeasureSpec, heightMeasureSpec); 65 } 66 67 @Override 68 public int getCompoundPaddingTop() { 69 return super.getCompoundPaddingTop() - mTopPaddingOffset; 70 } 71 72 @Override 73 public int getCompoundPaddingBottom() { 74 return super.getCompoundPaddingBottom() - mBottomPaddingOffset; 75 } 76 } 77
