| /* |
| * Copyright (C) 2015 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.calculator2; |
| |
| import android.content.Context; |
| import android.graphics.Paint; |
| import android.graphics.Rect; |
| import android.text.TextUtils; |
| import android.util.AttributeSet; |
| import android.widget.TextView; |
| |
| import java.nio.charset.Charset; |
| import java.nio.charset.CharsetEncoder; |
| |
| /** |
| * Extended {@link TextView} that supports ascent/baseline alignment. |
| */ |
| public class AlignedTextView extends TextView { |
| |
| private static final String LATIN_CAPITAL_LETTER = "H"; |
| private static final CharsetEncoder LATIN_CHARSET_ENCODER = |
| Charset.forName("ISO-8859-1").newEncoder(); |
| |
| // temporary rect for use during layout |
| private final Rect mTempRect = new Rect(); |
| |
| private int mTopPaddingOffset; |
| private int mBottomPaddingOffset; |
| |
| public AlignedTextView(Context context) { |
| this(context, null /* attrs */); |
| } |
| |
| public AlignedTextView(Context context, AttributeSet attrs) { |
| this(context, attrs, android.R.attr.textViewStyle); |
| } |
| |
| public AlignedTextView(Context context, AttributeSet attrs, int defStyleAttr) { |
| super(context, attrs, defStyleAttr); |
| |
| // Disable any included font padding by default. |
| setIncludeFontPadding(false); |
| } |
| |
| @Override |
| protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { |
| CharSequence text = getText(); |
| if (TextUtils.isEmpty(text) || LATIN_CHARSET_ENCODER.canEncode(text)) { |
| // For latin text align to the default capital letter height. |
| text = LATIN_CAPITAL_LETTER; |
| } |
| getPaint().getTextBounds(text.toString(), 0, text.length(), mTempRect); |
| |
| final Paint textPaint = getPaint(); |
| mTopPaddingOffset = Math.min(getPaddingTop(), |
| (int) Math.floor(mTempRect.top - textPaint.ascent())); |
| mBottomPaddingOffset = Math.min(getPaddingBottom(), |
| (int) Math.floor(textPaint.descent())); |
| |
| super.onMeasure(widthMeasureSpec, heightMeasureSpec); |
| } |
| |
| @Override |
| public int getCompoundPaddingTop() { |
| return super.getCompoundPaddingTop() - mTopPaddingOffset; |
| } |
| |
| @Override |
| public int getCompoundPaddingBottom() { |
| return super.getCompoundPaddingBottom() - mBottomPaddingOffset; |
| } |
| } |