content: /*
   * 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.view;
  
  import android.content.Context;
  import android.graphics.PixelFormat;
  import android.graphics.Rect;
  import android.util.Slog;
  import android.view.Gravity;
  import android.view.LayoutInflater;
  import android.view.View;
  import android.view.WindowManager;
  import android.view.WindowManagerGlobal;
  import android.widget.TextView;
  
  public class TooltipPopup {
      private static final String TAG = "TooltipPopup";
  
      private final Context mContext;
  
      private final View mContentView;
      private final TextView mMessageView;
  
      private final WindowManager.LayoutParams mLayoutParams = new WindowManager.LayoutParams();
      private final Rect mTmpDisplayFrame = new Rect();
      private final int[] mTmpAnchorPos = new int[2];
      private final int[] mTmpAppPos = new int[2];
  
      public TooltipPopup(Context context) {
          mContext = context;
  
          mContentView = LayoutInflater.from(mContext).inflate(
                  com.android.internal.R.layout.tooltip, null);
          mMessageView = (TextView) mContentView.findViewById(
                  com.android.internal.R.id.message);
  
          mLayoutParams.setTitle(
                  mContext.getString(com.android.internal.R.string.tooltip_popup_title));
          mLayoutParams.packageName = mContext.getOpPackageName();
          mLayoutParams.type = WindowManager.LayoutParams.TYPE_APPLICATION_ABOVE_SUB_PANEL;
          mLayoutParams.width = WindowManager.LayoutParams.WRAP_CONTENT;
          mLayoutParams.height = WindowManager.LayoutParams.WRAP_CONTENT;
          mLayoutParams.format = PixelFormat.TRANSLUCENT;
          mLayoutParams.windowAnimations = com.android.internal.R.style.Animation_Tooltip;
          mLayoutParams.flags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
                  | WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE;
      }
  
      public void show(View anchorView, int anchorX, int anchorY, boolean fromTouch,
              CharSequence tooltipText) {
          if (isShowing()) {
              hide();
          }
  
          mMessageView.setText(tooltipText);
  
          computePosition(anchorView, anchorX, anchorY, fromTouch, mLayoutParams);
  
          WindowManager wm = (WindowManager)mContext.getSystemService(Context.WINDOW_SERVICE);
          wm.addView(mContentView, mLayoutParams);
      }
  
      public void hide() {
          if (!isShowing()) {
              return;
          }
  
          WindowManager wm = (WindowManager)mContext.getSystemService(Context.WINDOW_SERVICE);
          wm.removeView(mContentView);
      }
  
      public View getContentView() {
          return mContentView;
      }
  
      public boolean isShowing() {
          return mContentView.getParent() != null;
      }
  
      private void computePosition(View anchorView, int anchorX, int anchorY, boolean fromTouch,
              WindowManager.LayoutParams outParams) {
          outParams.token = anchorView.getApplicationWindowToken();
  
          final int tooltipPreciseAnchorThreshold = mContext.getResources().getDimensionPixelOffset(
                  com.android.internal.R.dimen.tooltip_precise_anchor_threshold);
  
          final int offsetX;
          if (anchorView.getWidth() >= tooltipPreciseAnchorThreshold) {
              // Wide view. Align the tooltip horizontally to the precise X position.
              offsetX = anchorX;
          } else {
              // Otherwise anchor the tooltip to the view center.
              offsetX = anchorView.getWidth() / 2;  // Center on the view horizontally.
          }
  
          final int offsetBelow;
          final int offsetAbove;
          if (anchorView.getHeight() >= tooltipPreciseAnchorThreshold) {
              // Tall view. Align the tooltip vertically to the precise Y position.
              final int offsetExtra = mContext.getResources().getDimensionPixelOffset(
                      com.android.internal.R.dimen.tooltip_precise_anchor_extra_offset);
              offsetBelow = anchorY + offsetExtra;
              offsetAbove = anchorY - offsetExtra;
          } else {
              // Otherwise anchor the tooltip to the view center.
              offsetBelow = anchorView.getHeight();  // Place below the view in most cases.
              offsetAbove = 0;  // Place above the view if the tooltip does not fit below.
          }
  
          outParams.gravity = Gravity.CENTER_HORIZONTAL | Gravity.TOP;
  
          final int tooltipOffset = mContext.getResources().getDimensionPixelOffset(
                  fromTouch ? com.android.internal.R.dimen.tooltip_y_offset_touch
                          : com.android.internal.R.dimen.tooltip_y_offset_non_touch);
  
          // Find the main app window. The popup window will be positioned relative to it.
          final View appView = WindowManagerGlobal.getInstance().getWindowView(
                  anchorView.getApplicationWindowToken());
          if (appView == null) {
              Slog.e(TAG, "Cannot find app view");
              return;
          }
          appView.getWindowVisibleDisplayFrame(mTmpDisplayFrame);
          appView.getLocationOnScreen(mTmpAppPos);
  
          anchorView.getLocationOnScreen(mTmpAnchorPos);
          mTmpAnchorPos[0] -= mTmpAppPos[0];
          mTmpAnchorPos[1] -= mTmpAppPos[1];
          // mTmpAnchorPos is now relative to the main app window.
  
          outParams.x = mTmpAnchorPos[0] + offsetX - appView.getWidth() / 2;
  
          final int spec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
          mContentView.measure(spec, spec);
          final int tooltipHeight = mContentView.getMeasuredHeight();
  
          final int yAbove = mTmpAnchorPos[1] + offsetAbove - tooltipOffset - tooltipHeight;
          final int yBelow = mTmpAnchorPos[1] + offsetBelow + tooltipOffset;
          if (fromTouch) {
              if (yAbove >= 0) {
                  outParams.y = yAbove;
              } else {
                  outParams.y = yBelow;
              }
          } else {
              // Use mTmpDisplayFrame.height() as the lower boundary instead of appView.getHeight(),
              // as the latter includes the navigation bar, and tooltips do not look good over
              // the navigation bar.
              if (yBelow + tooltipHeight <= mTmpDisplayFrame.height()) {
                  outParams.y = yBelow;
              } else {
                  outParams.y = yAbove;
              }
          }
      }
  }
  