Notification MessagingStyle: Add handset views

Bug: 27250207
Change-Id: I499cf2beaeeb34f0f189815fc0911f3b8954bd50
diff --git a/core/java/com/android/internal/widget/MessagingLinearLayout.java b/core/java/com/android/internal/widget/MessagingLinearLayout.java
new file mode 100644
index 0000000..dc7b7f5
--- /dev/null
+++ b/core/java/com/android/internal/widget/MessagingLinearLayout.java
@@ -0,0 +1,278 @@
+/*
+ * 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.internal.widget;
+
+import com.android.internal.R;
+
+import android.annotation.Nullable;
+import android.content.Context;
+import android.content.res.TypedArray;
+import android.graphics.Canvas;
+import android.util.AttributeSet;
+import android.view.RemotableViewMethod;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.RemoteViews;
+
+/**
+ * A custom-built layout for the Notification.MessagingStyle.
+ *
+ * Evicts children until they all fit.
+ */
+@RemoteViews.RemoteView
+public class MessagingLinearLayout extends ViewGroup {
+
+    /**
+     * Spacing to be applied between views.
+     */
+    private int mSpacing;
+
+    /**
+     * The maximum height allowed.
+     */
+    private int mMaxHeight;
+
+    private int mIndentLines;
+
+    public MessagingLinearLayout(Context context, @Nullable AttributeSet attrs) {
+        super(context, attrs);
+
+        final TypedArray a = context.obtainStyledAttributes(attrs,
+                R.styleable.MessagingLinearLayout, 0,
+                0);
+
+        final int N = a.getIndexCount();
+        for (int i = 0; i < N; i++) {
+            int attr = a.getIndex(i);
+            switch (attr) {
+                case R.styleable.MessagingLinearLayout_maxHeight:
+                    mMaxHeight = a.getDimensionPixelSize(i, 0);
+                    break;
+                case R.styleable.MessagingLinearLayout_spacing:
+                    mSpacing = a.getDimensionPixelSize(i, 0);
+                    break;
+            }
+        }
+
+        if (mMaxHeight <= 0) {
+            throw new IllegalStateException(
+                    "MessagingLinearLayout: Must specify positive maxHeight");
+        }
+
+        a.recycle();
+    }
+
+
+    @Override
+    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+        // This is essentially a bottom-up linear layout that only adds children that fit entirely
+        // up to a maximum height.
+
+        switch (MeasureSpec.getMode(heightMeasureSpec)) {
+            case MeasureSpec.AT_MOST:
+                heightMeasureSpec = MeasureSpec.makeMeasureSpec(
+                        Math.min(mMaxHeight, MeasureSpec.getSize(heightMeasureSpec)),
+                        MeasureSpec.AT_MOST);
+                break;
+            case MeasureSpec.UNSPECIFIED:
+                heightMeasureSpec = MeasureSpec.makeMeasureSpec(
+                        mMaxHeight,
+                        MeasureSpec.AT_MOST);
+                break;
+            case MeasureSpec.EXACTLY:
+                break;
+        }
+        final int targetHeight = MeasureSpec.getSize(heightMeasureSpec);
+        final int count = getChildCount();
+
+        for (int i = 0; i < count; ++i) {
+            final View child = getChildAt(i);
+            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
+            lp.hide = true;
+        }
+
+        int totalHeight = mPaddingTop + mPaddingBottom;
+        boolean first = true;
+
+        // Starting from the bottom: we measure every view as if it were the only one. If it still
+        // fits, we take it, otherwise we stop there.
+        for (int i = count - 1; i >= 0 && totalHeight < targetHeight; i--) {
+            if (getChildAt(i).getVisibility() == GONE) {
+                continue;
+            }
+            final View child = getChildAt(i);
+            LayoutParams lp = (LayoutParams) getChildAt(i).getLayoutParams();
+
+            if (child instanceof ImageFloatingTextView) {
+                // Pretend we need the image padding for all views, we don't know which
+                // one will end up needing to do this (might end up not using all the space,
+                // but calculating this exactly would be more expensive).
+                ((ImageFloatingTextView) child).setNumIndentLines(mIndentLines);
+            }
+
+            measureChildWithMargins(child, widthMeasureSpec, 0, heightMeasureSpec, 0);
+
+            final int childHeight = child.getMeasuredHeight();
+            int newHeight = Math.max(totalHeight, totalHeight + childHeight + lp.topMargin +
+                    lp.bottomMargin + (first ? 0 : mSpacing));
+            first = false;
+
+            if (newHeight <= targetHeight) {
+                totalHeight = newHeight;
+                lp.hide = false;
+            } else {
+                break;
+            }
+        }
+
+        // Now that we know which views to take, fix up the indents and see what width we get.
+        int measuredWidth = mPaddingLeft + mPaddingRight;
+        int imageLines = mIndentLines;
+        for (int i = 0; i < count; i++) {
+            final View child = getChildAt(i);
+            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
+
+            if (child.getVisibility() == GONE || lp.hide) {
+                continue;
+            }
+
+            if (child instanceof ImageFloatingTextView) {
+                ImageFloatingTextView textChild = (ImageFloatingTextView) child;
+                if (imageLines == 2 && textChild.getLineCount() > 2) {
+                    // HACK: If we need indent for two lines, and they're coming from the same
+                    // view, we need extra spacing to compensate for the lack of margins,
+                    // so add an extra line of indent.
+                    imageLines = 3;
+                }
+                boolean changed = textChild.setNumIndentLines(Math.max(0, imageLines));
+                if (changed) {
+                    measureChildWithMargins(child, widthMeasureSpec, 0, heightMeasureSpec, 0);
+                }
+                imageLines -= textChild.getLineCount();
+            }
+
+            measuredWidth = Math.max(measuredWidth,
+                    child.getMeasuredWidth() + lp.leftMargin + lp.rightMargin
+                            + mPaddingLeft + mPaddingRight);
+        }
+
+
+        setMeasuredDimension(
+                resolveSize(Math.max(getSuggestedMinimumWidth(), measuredWidth),
+                        widthMeasureSpec),
+                resolveSize(Math.max(getSuggestedMinimumHeight(), totalHeight),
+                        heightMeasureSpec));
+    }
+
+    @Override
+    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
+        final int paddingLeft = mPaddingLeft;
+
+        int childTop;
+
+        // Where right end of child should go
+        final int width = right - left;
+        final int childRight = width - mPaddingRight;
+
+        final int layoutDirection = getLayoutDirection();
+        final int count = getChildCount();
+
+        childTop = mPaddingTop;
+
+        boolean first = true;
+
+        for (int i = 0; i < count; i++) {
+            final View child = getChildAt(i);
+            final LayoutParams lp = (LayoutParams) child.getLayoutParams();
+
+            if (child.getVisibility() == GONE || lp.hide) {
+                continue;
+            }
+
+            final int childWidth = child.getMeasuredWidth();
+            final int childHeight = child.getMeasuredHeight();
+
+            int childLeft;
+            if (layoutDirection == LAYOUT_DIRECTION_RTL) {
+                childLeft = childRight - childWidth - lp.rightMargin;
+            } else {
+                childLeft = paddingLeft + lp.leftMargin;
+            }
+
+            if (!first) {
+                childTop += mSpacing;
+            }
+
+            childTop += lp.topMargin;
+            child.layout(childLeft, childTop, childLeft + childWidth, childTop + childHeight);
+
+            childTop += childHeight + lp.bottomMargin;
+
+            first = false;
+        }
+    }
+
+    @Override
+    protected boolean drawChild(Canvas canvas, View child, long drawingTime) {
+        final LayoutParams lp = (LayoutParams) child.getLayoutParams();
+        if (lp.hide) {
+            return true;
+        }
+        return super.drawChild(canvas, child, drawingTime);
+    }
+
+    @Override
+    public LayoutParams generateLayoutParams(AttributeSet attrs) {
+        return new LayoutParams(mContext, attrs);
+    }
+
+    @Override
+    protected LayoutParams generateDefaultLayoutParams() {
+        return new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
+
+    }
+
+    @Override
+    protected LayoutParams generateLayoutParams(ViewGroup.LayoutParams lp) {
+        LayoutParams copy = new LayoutParams(lp.width, lp.height);
+        if (lp instanceof MarginLayoutParams) {
+            copy.copyMarginsFrom((MarginLayoutParams) lp);
+        }
+        return copy;
+    }
+
+    @RemotableViewMethod
+    /**
+     * Sets how many lines should be indented to avoid a floating image.
+     */
+    public void setNumIndentLines(int numberLines) {
+        mIndentLines = numberLines;
+    }
+
+    public static class LayoutParams extends MarginLayoutParams {
+
+        boolean hide = false;
+
+        public LayoutParams(Context c, AttributeSet attrs) {
+            super(c, attrs);
+        }
+
+        public LayoutParams(int width, int height) {
+            super(width, height);
+        }
+    }
+}