Create messenger preview screen for magnification gesture

settings screen

Change-Id: I4824c370388c4996e233c87005879d4818cfd59e

src/com/android/settings/display/MessageBubbleBackground.java

@@ -0,0 +1,51 @@
+/*
+ * 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.settings.display;
+
+import android.content.Context;
+import android.util.AttributeSet;
+import android.util.Log;
+import android.widget.LinearLayout;
+
+import com.android.settings.R;
+
+public class MessageBubbleBackground extends LinearLayout {
+    private final  int mSnapWidthPixels;
+
+    public MessageBubbleBackground(Context context, AttributeSet attrs) {
+        super(context, attrs);
+        mSnapWidthPixels = context.getResources().getDimensionPixelSize(
+                R.dimen.conversation_bubble_width_snap);
+    }
+
+    @Override
+    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
+        final int widthPadding = getPaddingLeft() + getPaddingRight();
+        int bubbleWidth = getMeasuredWidth() - widthPadding;
+        final int maxWidth = MeasureSpec.getSize(widthMeasureSpec) - widthPadding;
+        // Round up to next snapWidthPixels
+        bubbleWidth = Math.min(maxWidth,
+                (int) (Math.ceil(bubbleWidth / (float) mSnapWidthPixels) * mSnapWidthPixels));
+        super.onMeasure(
+                MeasureSpec.makeMeasureSpec(bubbleWidth + widthPadding, MeasureSpec.EXACTLY),
+                heightMeasureSpec);
+        Log.w(this.getClass().getSimpleName(),
+                String.format("onMeasure called; width:%d, height:%d", this.getMeasuredWidth(),
+                        this.getMeasuredHeight()));
+    }
+}