src/com/android/calculator2/SquareLinearLayout.java

/*
 * Copyright (C) 2013 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.widget.LinearLayout;

public class SquareLinearLayout extends LinearLayout {
    public SquareLinearLayout(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        final int widthMode = MeasureSpec.getMode(widthMeasureSpec);
        final int widthSize = MeasureSpec.getSize(widthMeasureSpec);
        final int heightMode = MeasureSpec.getMode(heightMeasureSpec);
        final int heightSize = MeasureSpec.getSize(heightMeasureSpec);

        final int size;
        if (widthMode == MeasureSpec.EXACTLY && widthSize > 0) {
            size = widthSize;
        } else if (heightMode == MeasureSpec.EXACTLY && heightSize > 0) {
            size = heightSize;
        } else {
            size = widthSize < heightSize ? widthSize : heightSize;
        }

        final int finalMeasureSpec = MeasureSpec.makeMeasureSpec(size, MeasureSpec.EXACTLY);
        super.onMeasure(finalMeasureSpec, finalMeasureSpec);
    }
}