/*
* Copyright 2015 Google Inc. All rights reserved.
*
* 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.google.samples.apps.iosched.ui.widget;
import android.content.Context;
import android.content.res.TypedArray;
import android.util.AttributeSet;
import android.widget.FrameLayout;
import com.google.samples.apps.iosched.R;
/**
* Extension of FrameLayout that assumes a measured (non-zero) width and sets the
* height according to the provided aspect ratio.
*/
public class AspectRatioView extends FrameLayout {
private float mAspectRatio = 0f;
public AspectRatioView(Context context) {
this(context, null, 0);
}
public AspectRatioView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public AspectRatioView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
final TypedArray a = context.obtainStyledAttributes(attrs,
R.styleable.AspectRatioView, defStyle, 0);
mAspectRatio = a.getFloat(R.styleable.AspectRatioView_aspectRatio, 0);
if (mAspectRatio == 0f) {
throw new IllegalArgumentException(
"You must specify an aspect ratio when using AspectRatioView.");
}
a.recycle();
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
if (mAspectRatio != 0) {
final int width = MeasureSpec.getSize(widthMeasureSpec);
final int height = (int) (width / mAspectRatio);
super.onMeasure(
MeasureSpec.makeMeasureSpec(width, MeasureSpec.EXACTLY),
MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY));
} else {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
}
}