| /* |
| * Copyright (C) 2016 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.util.AttributeSet; |
| import android.view.View; |
| import android.view.ViewGroup; |
| import android.widget.HorizontalScrollView; |
| |
| import static android.view.View.MeasureSpec.UNSPECIFIED; |
| import static android.view.ViewGroup.LayoutParams.MATCH_PARENT; |
| import static android.view.ViewGroup.LayoutParams.WRAP_CONTENT; |
| |
| public class CalculatorScrollView extends HorizontalScrollView { |
| |
| public CalculatorScrollView(Context context) { |
| this(context, null /* attrs */); |
| } |
| |
| public CalculatorScrollView(Context context, AttributeSet attrs) { |
| this(context, attrs, 0 /* defStyleAttr */); |
| } |
| |
| public CalculatorScrollView(Context context, AttributeSet attrs, int defStyleAttr) { |
| super(context, attrs, defStyleAttr); |
| } |
| |
| private static int getChildMeasureSpecCompat(int spec, int padding, int childDimension) { |
| if (MeasureSpec.getMode(spec) == UNSPECIFIED |
| && (childDimension == MATCH_PARENT || childDimension == WRAP_CONTENT)) { |
| final int size = Math.max(0, MeasureSpec.getSize(spec) - padding); |
| return MeasureSpec.makeMeasureSpec(size, UNSPECIFIED); |
| } |
| return ViewGroup.getChildMeasureSpec(spec, padding, childDimension); |
| } |
| |
| @Override |
| protected void measureChild(View child, int parentWidthMeasureSpec, |
| int parentHeightMeasureSpec) { |
| // Allow child to be as wide as they want. |
| parentWidthMeasureSpec = MeasureSpec.makeMeasureSpec( |
| MeasureSpec.getSize(parentWidthMeasureSpec), UNSPECIFIED); |
| |
| final ViewGroup.LayoutParams lp = child.getLayoutParams(); |
| final int childWidthMeasureSpec = getChildMeasureSpecCompat(parentWidthMeasureSpec, |
| 0 /* padding */, lp.width); |
| final int childHeightMeasureSpec = getChildMeasureSpecCompat(parentHeightMeasureSpec, |
| getPaddingTop() + getPaddingBottom(), lp.height); |
| |
| child.measure(childWidthMeasureSpec, childHeightMeasureSpec); |
| } |
| |
| @Override |
| protected void measureChildWithMargins(View child, int parentWidthMeasureSpec, int widthUsed, |
| int parentHeightMeasureSpec, int heightUsed) { |
| // Allow child to be as wide as they want. |
| parentWidthMeasureSpec = MeasureSpec.makeMeasureSpec( |
| MeasureSpec.getSize(parentWidthMeasureSpec), UNSPECIFIED); |
| |
| final MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams(); |
| final int childWidthMeasureSpec = getChildMeasureSpecCompat(parentWidthMeasureSpec, |
| lp.leftMargin + lp.rightMargin, lp.width); |
| final int childHeightMeasureSpec = getChildMeasureSpecCompat(parentHeightMeasureSpec, |
| getPaddingTop() + getPaddingBottom() + lp.topMargin + lp.bottomMargin, lp.height); |
| |
| child.measure(childWidthMeasureSpec, childHeightMeasureSpec); |
| } |
| } |