🔍 Yank out measurement logic for FirstRun pages

chrome/android/java/src/org/chromium/chrome/browser/firstrun/FirstRunChooserView.java

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.firstrun;
+
+import android.content.Context;
+import android.util.AttributeSet;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.ScrollView;
+
+import org.chromium.chrome.R;
+
+/**
+ * View that is used when asking the user to choose between options during First Run.
+ *
+ * Manages the appearance of a large header at the top of the dialog.
+ */
+public class FirstRunChooserView extends ScrollView {
+    private View mChooserTitleView;
+
+    public FirstRunChooserView(Context context, AttributeSet attrs) {
+        super(context, attrs);
+    }
+
+    @Override
+    protected void onFinishInflate() {
+        super.onFinishInflate();
+        mChooserTitleView = findViewById(R.id.chooser_title);
+    }
+
+    @Override
+    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+        // This assumes that view's layout_width and layout_height are set to match_parent.
+        assert MeasureSpec.getMode(widthMeasureSpec) == MeasureSpec.EXACTLY;
+        assert MeasureSpec.getMode(heightMeasureSpec) == MeasureSpec.EXACTLY;
+
+        int width = MeasureSpec.getSize(widthMeasureSpec);
+        int height = MeasureSpec.getSize(heightMeasureSpec);
+
+        ViewGroup.LayoutParams params = mChooserTitleView.getLayoutParams();
+        if (height > width) {
+            // Sets the title aspect ratio to be 16:9.
+            params.height = width * 9 / 16;
+            mChooserTitleView.setPadding(mChooserTitleView.getPaddingLeft(), 0,
+                    mChooserTitleView.getPaddingRight(), mChooserTitleView.getPaddingBottom());
+        } else {
+            params.height = ViewGroup.LayoutParams.WRAP_CONTENT;
+
+            // Adds top padding.
+            mChooserTitleView.setPadding(mChooserTitleView.getPaddingLeft(),
+                    getResources().getDimensionPixelOffset(R.dimen.signin_screen_top_padding),
+                    mChooserTitleView.getPaddingRight(), mChooserTitleView.getPaddingBottom());
+        }
+        mChooserTitleView.setLayoutParams(params);
+
+        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
+    }
+
+    @Override
+    protected float getTopFadingEdgeStrength() {
+        // Disable fading out effect at the top of this ScrollView.
+        return 0;
+    }
+}