core/java/android/view/NotificationHeaderView.java

/*
 * 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 android.view;

import android.annotation.Nullable;
import android.content.Context;
import android.content.res.TypedArray;
import android.util.AttributeSet;
import android.widget.LinearLayout;
import android.widget.RemoteViews;

import com.android.internal.R;

/**
 * A header of a notification view
 *
 * @hide
 */
@RemoteViews.RemoteView
public class NotificationHeaderView extends LinearLayout {
    private final int mHeaderMinWidth;
    private View mAppName;
    private View mSubTextView;

    public NotificationHeaderView(Context context) {
        this(context, null);
    }

    public NotificationHeaderView(Context context, @Nullable AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public NotificationHeaderView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        this(context, attrs, defStyleAttr, 0);
    }

    public NotificationHeaderView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
        mHeaderMinWidth = getResources().getDimensionPixelSize(
                com.android.internal.R.dimen.notification_header_shrink_min_width);
    }

    @Override
    protected void onFinishInflate() {
        super.onFinishInflate();
        mAppName = findViewById(com.android.internal.R.id.app_name_text);
        mSubTextView = findViewById(com.android.internal.R.id.header_sub_text);
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        final int givenWidth = MeasureSpec.getSize(widthMeasureSpec);
        final int givenHeight = MeasureSpec.getSize(heightMeasureSpec);
        int wrapContentWidthSpec = MeasureSpec.makeMeasureSpec(givenWidth,
                MeasureSpec.AT_MOST);
        int wrapContentHeightSpec = MeasureSpec.makeMeasureSpec(givenHeight,
                MeasureSpec.AT_MOST);
        int totalWidth = getPaddingStart() + getPaddingEnd();
        for (int i = 0; i < getChildCount(); i++) {
            final View child = getChildAt(i);
            if (child.getVisibility() == GONE) {
                // We'll give it the rest of the space in the end
                continue;
            }
            final MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();
            int childWidthSpec = getChildMeasureSpec(wrapContentWidthSpec,
                    lp.leftMargin + lp.rightMargin, lp.width);
            int childHeightSpec = getChildMeasureSpec(wrapContentHeightSpec,
                    lp.topMargin + lp.bottomMargin, lp.height);
            child.measure(childWidthSpec, childHeightSpec);
            totalWidth += lp.leftMargin + lp.rightMargin + child.getMeasuredWidth();
        }
        if (totalWidth > givenWidth) {
            int overFlow = totalWidth - givenWidth;
            // We are overflowing, lets shrink
            final int appWidth = mAppName.getMeasuredWidth();
            if (appWidth > mHeaderMinWidth) {
                int newSize = appWidth - Math.min(appWidth - mHeaderMinWidth, overFlow);
                int childWidthSpec = MeasureSpec.makeMeasureSpec(newSize, MeasureSpec.AT_MOST);
                mAppName.measure(childWidthSpec, wrapContentHeightSpec);
                overFlow -= appWidth - newSize;
            }
            if (overFlow > 0 && mSubTextView.getVisibility() != GONE) {
                // we're still too big
                final int subTextWidth = mSubTextView.getMeasuredWidth();
                int newSize = Math.max(0, subTextWidth - overFlow);
                int childWidthSpec = MeasureSpec.makeMeasureSpec(newSize, MeasureSpec.AT_MOST);
                mSubTextView.measure(childWidthSpec, wrapContentHeightSpec);
            }
            totalWidth = givenWidth;
        }
        setMeasuredDimension(totalWidth, givenHeight);
    }
}