car-ui-lib/src/com/android/car/ui/core/BaseLayoutController.java - platform/packages/apps/Car/libs - Git at Google

 /*
  * Copyright (C) 2020 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.car.ui.core;

 import static com.android.car.ui.utils.CarUiUtils.requireViewByRefId;

 import android.app.Activity;
 import android.content.res.TypedArray;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.view.ViewTreeObserver;
 import android.widget.FrameLayout;

 import androidx.annotation.LayoutRes;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.fragment.app.Fragment;
 import androidx.fragment.app.FragmentActivity;

 import com.android.car.ui.R;
 import com.android.car.ui.baselayout.Insets;
 import com.android.car.ui.baselayout.InsetsChangedListener;
 import com.android.car.ui.toolbar.ToolbarController;
 import com.android.car.ui.toolbar.ToolbarControllerImpl;

 import java.util.HashMap;
 import java.util.Map;

 /**
  * BaseLayoutController accepts an {@link Activity} and sets up the base layout inside of it.
  * It also exposes a {@link ToolbarController} to access the toolbar. This may be null if
  * used with a base layout without a Toolbar.
  */
 class BaseLayoutController {

     private static Map<Activity, BaseLayoutController> sBaseLayoutMap = new HashMap<>();

     private InsetsUpdater mInsetsUpdater;

     /**
      * Gets a BaseLayoutController for the given {@link Activity}. Must have called
      * {@link #build(Activity)} with the same activity earlier, otherwise will return null.
      */
     @Nullable
     /* package */ static BaseLayoutController getBaseLayout(Activity activity) {
         return sBaseLayoutMap.get(activity);
     }

     @Nullable
     private ToolbarController mToolbarController;

     private BaseLayoutController(Activity activity) {
         installBaseLayout(activity);
     }

     /**
      * Create a new BaseLayoutController for the given {@link Activity}.
      *
      * <p>You can get a reference to it by calling {@link #getBaseLayout(Activity)}.
      */
     /* package */ static void build(Activity activity) {
         sBaseLayoutMap.put(activity, new BaseLayoutController(activity));
     }

     /**
      * Destroy the BaseLayoutController for the given {@link Activity}.
      */
     /* package */ static void destroy(Activity activity) {
         sBaseLayoutMap.remove(activity);
     }

     /**
      * Gets the {@link ToolbarController} for activities created with carUiBaseLayout and
      * carUiToolbar set to true.
      */
     @Nullable
     /* package */ ToolbarController getToolbarController() {
         return mToolbarController;
     }

     /* package */ Insets getInsets() {
         return mInsetsUpdater.getInsets();
     }

     /**
      * Installs the base layout into an activity, moving its content view under the base layout.
      *
      * <p>This function must be called during the onCreate() of the {@link Activity}.
      *
      * @param activity The {@link Activity} to install a base layout in.
      */
     private void installBaseLayout(Activity activity) {
         boolean baseLayoutEnabled = getThemeBoolean(activity, R.attr.carUiBaseLayout);
         boolean toolbarEnabled = getThemeBoolean(activity, R.attr.carUiToolbar);
         if (!baseLayoutEnabled) {
             return;
         }

         @LayoutRes final int baseLayoutRes = toolbarEnabled
                 ? R.layout.car_ui_base_layout_toolbar
                 : R.layout.car_ui_base_layout;

         View baseLayout = LayoutInflater.from(activity)
                 .inflate(baseLayoutRes, null, false);

         // Replace windowContentView with baseLayout
         ViewGroup windowContentView = activity.getWindow().findViewById(android.R.id.content);
         ViewGroup contentViewParent = (ViewGroup) windowContentView.getParent();
         int contentIndex = contentViewParent.indexOfChild(windowContentView);
         contentViewParent.removeView(windowContentView);
         contentViewParent.addView(baseLayout, contentIndex, windowContentView.getLayoutParams());

         // Add windowContentView to the baseLayout's content view
         FrameLayout contentView = requireViewByRefId(baseLayout, R.id.content);
         contentView.addView(windowContentView, new FrameLayout.LayoutParams(
                 ViewGroup.LayoutParams.MATCH_PARENT,
                 ViewGroup.LayoutParams.MATCH_PARENT));

         if (toolbarEnabled) {
             mToolbarController = new ToolbarControllerImpl(baseLayout);
         }

         mInsetsUpdater = new InsetsUpdater(activity, baseLayout, windowContentView);
         mInsetsUpdater.installListeners();
     }

     /**
      * Gets the boolean value of an Attribute from an {@link Activity Activity's}
      * {@link android.content.res.Resources.Theme}.
      */
     private boolean getThemeBoolean(Activity activity, int attr) {
         TypedArray a = activity.getTheme().obtainStyledAttributes(new int[] { attr });

         try {
             return a.getBoolean(0, false);
         } finally {
             a.recycle();
         }
     }

     /**
      * InsetsUpdater waits for layout changes, and when there is one, calculates the appropriate
      * insets into the content view.
      *
      * <p>It then calls {@link InsetsChangedListener#onCarUiInsetsChanged(Insets)} on the
      * {@link Activity} and any {@link Fragment Fragments} the Activity might have. If
      * none of the Activity/Fragments implement {@link InsetsChangedListener}, it will set
      * padding on the content view equal to the insets.
      */
     private static class InsetsUpdater implements ViewTreeObserver.OnGlobalLayoutListener {
         // These tags mark views that should overlay the content view in the base layout.
         // OEMs should add them to views in their base layout, ie: android:tag="car_ui_left_inset"
         // Apps will then be able to draw under these views, but will be encouraged to not put
         // any user-interactable content there.
         private static final String LEFT_INSET_TAG = "car_ui_left_inset";
         private static final String RIGHT_INSET_TAG = "car_ui_right_inset";
         private static final String TOP_INSET_TAG = "car_ui_top_inset";
         private static final String BOTTOM_INSET_TAG = "car_ui_bottom_inset";

         private final Activity mActivity;
         private final View mLeftInsetView;
         private final View mRightInsetView;
         private final View mTopInsetView;
         private final View mBottomInsetView;

         private boolean mInsetsDirty = true;
         @NonNull
         private Insets mInsets = new Insets();

         /**
          * Constructs an InsetsUpdater that calculates and dispatches insets to an {@link Activity}.
          *
          * @param activity The activity that is using base layouts
          * @param baseLayout The root view of the base layout
          * @param contentView The android.R.id.content View
          */
         InsetsUpdater(Activity activity, View baseLayout, View contentView) {
             mActivity = activity;

             mLeftInsetView = baseLayout.findViewWithTag(LEFT_INSET_TAG);
             mRightInsetView = baseLayout.findViewWithTag(RIGHT_INSET_TAG);
             mTopInsetView = baseLayout.findViewWithTag(TOP_INSET_TAG);
             mBottomInsetView = baseLayout.findViewWithTag(BOTTOM_INSET_TAG);

             final View.OnLayoutChangeListener layoutChangeListener =
                     (View v, int left, int top, int right, int bottom,
                             int oldLeft, int oldTop, int oldRight, int oldBottom) -> {
                         if (left != oldLeft || top != oldTop
                                 || right != oldRight || bottom != oldBottom) {
                             mInsetsDirty = true;
                         }
                     };

             if (mLeftInsetView != null) {
                 mLeftInsetView.addOnLayoutChangeListener(layoutChangeListener);
             }
             if (mRightInsetView != null) {
                 mRightInsetView.addOnLayoutChangeListener(layoutChangeListener);
             }
             if (mTopInsetView != null) {
                 mTopInsetView.addOnLayoutChangeListener(layoutChangeListener);
             }
             if (mBottomInsetView != null) {
                 mBottomInsetView.addOnLayoutChangeListener(layoutChangeListener);
             }
             contentView.addOnLayoutChangeListener(layoutChangeListener);
         }

         /**
          * Install a global layout listener, during which the insets will be recalculated and
          * dispatched.
          */
         void installListeners() {
             // The global layout listener will run after all the individual layout change listeners
             // so that we only updateInsets once per layout, even if multiple inset views changed
             mActivity.getWindow().getDecorView().getViewTreeObserver()
                     .addOnGlobalLayoutListener(this);
         }

         @NonNull
         Insets getInsets() {
             return mInsets;
         }

         /**
          * onGlobalLayout() should recalculate the amount of insets we need, and then dispatch them.
          */
         @Override
         public void onGlobalLayout() {
             if (!mInsetsDirty) {
                 return;
             }

             View content = mActivity.requireViewById(android.R.id.content);

             // Calculate how much each inset view overlays the content view
             int top, bottom, left, right;
             top = bottom = left = right = 0;
             if (mTopInsetView != null) {
                 top = Math.max(0, getBottomOfView(mTopInsetView) - getTopOfView(content));
             }
             if (mBottomInsetView != null) {
                 bottom = Math.max(0, getBottomOfView(content) - getTopOfView(mBottomInsetView));
             }
             if (mLeftInsetView != null) {
                 left = Math.max(0, getRightOfView(mLeftInsetView) - getLeftOfView(content));
             }
             if (mRightInsetView != null) {
                 right = Math.max(0, getRightOfView(content) - getLeftOfView(mRightInsetView));
             }
             Insets insets = new Insets(left, top, right, bottom);

             mInsetsDirty = false;
             if (!insets.equals(mInsets)) {
                 mInsets = insets;
                 dispatchNewInsets(insets);
             }
         }

         /**
          * Dispatch the new {@link Insets} to the {@link Activity} and all of its
          * {@link Fragment Fragments}. If none of those implement {@link InsetsChangedListener},
          * we will set the value of the insets as padding on the content view.
          *
          * @param insets The newly-changed insets.
          */
         private void dispatchNewInsets(Insets insets) {
             boolean handled = false;
             if (mActivity instanceof InsetsChangedListener) {
                 ((InsetsChangedListener) mActivity).onCarUiInsetsChanged(insets);
                 handled = true;
             }

             if (mActivity instanceof FragmentActivity) {
                 for (Fragment fragment : ((FragmentActivity) mActivity).getSupportFragmentManager()
                         .getFragments()) {
                     if (fragment instanceof InsetsChangedListener) {
                         ((InsetsChangedListener) fragment).onCarUiInsetsChanged(insets);
                         handled = true;
                     }
                 }
             }

             if (!handled) {
                 mActivity.requireViewById(android.R.id.content).setPadding(
                         insets.getLeft(), insets.getTop(), insets.getRight(), insets.getBottom());
             }
         }

         private static int getLeftOfView(View v) {
             int[] position = new int[2];
             v.getLocationOnScreen(position);
             return position[0];
         }

         private static int getRightOfView(View v) {
             int[] position = new int[2];
             v.getLocationOnScreen(position);
             return position[0] + v.getWidth();
         }

         private static int getTopOfView(View v) {
             int[] position = new int[2];
             v.getLocationOnScreen(position);
             return position[1];
         }

         private static int getBottomOfView(View v) {
             int[] position = new int[2];
             v.getLocationOnScreen(position);
             return position[1] + v.getHeight();
         }
     }
 }
	/*
	* Copyright (C) 2020 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.car.ui.core;

	import static com.android.car.ui.utils.CarUiUtils.requireViewByRefId;

	import android.app.Activity;
	import android.content.res.TypedArray;
	import android.view.LayoutInflater;
	import android.view.View;
	import android.view.ViewGroup;
	import android.view.ViewTreeObserver;
	import android.widget.FrameLayout;

	import androidx.annotation.LayoutRes;
	import androidx.annotation.NonNull;
	import androidx.annotation.Nullable;
	import androidx.fragment.app.Fragment;
	import androidx.fragment.app.FragmentActivity;

	import com.android.car.ui.R;
	import com.android.car.ui.baselayout.Insets;
	import com.android.car.ui.baselayout.InsetsChangedListener;
	import com.android.car.ui.toolbar.ToolbarController;
	import com.android.car.ui.toolbar.ToolbarControllerImpl;

	import java.util.HashMap;
	import java.util.Map;

	/**
	* BaseLayoutController accepts an {@link Activity} and sets up the base layout inside of it.
	* It also exposes a {@link ToolbarController} to access the toolbar. This may be null if
	* used with a base layout without a Toolbar.
	*/
	class BaseLayoutController {

	private static Map<Activity, BaseLayoutController> sBaseLayoutMap = new HashMap<>();

	private InsetsUpdater mInsetsUpdater;

	/**
	* Gets a BaseLayoutController for the given {@link Activity}. Must have called
	* {@link #build(Activity)} with the same activity earlier, otherwise will return null.
	*/
	@Nullable
	/* package */ static BaseLayoutController getBaseLayout(Activity activity) {
	return sBaseLayoutMap.get(activity);
	}

	@Nullable
	private ToolbarController mToolbarController;

	private BaseLayoutController(Activity activity) {
	installBaseLayout(activity);
	}

	/**
	* Create a new BaseLayoutController for the given {@link Activity}.
	*
	* <p>You can get a reference to it by calling {@link #getBaseLayout(Activity)}.
	*/
	/* package */ static void build(Activity activity) {
	sBaseLayoutMap.put(activity, new BaseLayoutController(activity));
	}

	/**
	* Destroy the BaseLayoutController for the given {@link Activity}.
	*/
	/* package */ static void destroy(Activity activity) {
	sBaseLayoutMap.remove(activity);
	}

	/**
	* Gets the {@link ToolbarController} for activities created with carUiBaseLayout and
	* carUiToolbar set to true.
	*/
	@Nullable
	/* package */ ToolbarController getToolbarController() {
	return mToolbarController;
	}

	/* package */ Insets getInsets() {
	return mInsetsUpdater.getInsets();
	}

	/**
	* Installs the base layout into an activity, moving its content view under the base layout.
	*
	* <p>This function must be called during the onCreate() of the {@link Activity}.
	*
	* @param activity The {@link Activity} to install a base layout in.
	*/
	private void installBaseLayout(Activity activity) {
	boolean baseLayoutEnabled = getThemeBoolean(activity, R.attr.carUiBaseLayout);
	boolean toolbarEnabled = getThemeBoolean(activity, R.attr.carUiToolbar);
	if (!baseLayoutEnabled) {
	return;
	}

	@LayoutRes final int baseLayoutRes = toolbarEnabled
	? R.layout.car_ui_base_layout_toolbar
	: R.layout.car_ui_base_layout;

	View baseLayout = LayoutInflater.from(activity)
	.inflate(baseLayoutRes, null, false);

	// Replace windowContentView with baseLayout
	ViewGroup windowContentView = activity.getWindow().findViewById(android.R.id.content);
	ViewGroup contentViewParent = (ViewGroup) windowContentView.getParent();
	int contentIndex = contentViewParent.indexOfChild(windowContentView);
	contentViewParent.removeView(windowContentView);
	contentViewParent.addView(baseLayout, contentIndex, windowContentView.getLayoutParams());

	// Add windowContentView to the baseLayout's content view
	FrameLayout contentView = requireViewByRefId(baseLayout, R.id.content);
	contentView.addView(windowContentView, new FrameLayout.LayoutParams(
	ViewGroup.LayoutParams.MATCH_PARENT,
	ViewGroup.LayoutParams.MATCH_PARENT));

	if (toolbarEnabled) {
	mToolbarController = new ToolbarControllerImpl(baseLayout);
	}

	mInsetsUpdater = new InsetsUpdater(activity, baseLayout, windowContentView);
	mInsetsUpdater.installListeners();
	}

	/**
	* Gets the boolean value of an Attribute from an {@link Activity Activity's}
	* {@link android.content.res.Resources.Theme}.
	*/
	private boolean getThemeBoolean(Activity activity, int attr) {
	TypedArray a = activity.getTheme().obtainStyledAttributes(new int[] { attr });

	try {
	return a.getBoolean(0, false);
	} finally {
	a.recycle();
	}
	}

	/**
	* InsetsUpdater waits for layout changes, and when there is one, calculates the appropriate
	* insets into the content view.
	*
	* <p>It then calls {@link InsetsChangedListener#onCarUiInsetsChanged(Insets)} on the
	* {@link Activity} and any {@link Fragment Fragments} the Activity might have. If
	* none of the Activity/Fragments implement {@link InsetsChangedListener}, it will set
	* padding on the content view equal to the insets.
	*/
	private static class InsetsUpdater implements ViewTreeObserver.OnGlobalLayoutListener {
	// These tags mark views that should overlay the content view in the base layout.
	// OEMs should add them to views in their base layout, ie: android:tag="car_ui_left_inset"
	// Apps will then be able to draw under these views, but will be encouraged to not put
	// any user-interactable content there.
	private static final String LEFT_INSET_TAG = "car_ui_left_inset";
	private static final String RIGHT_INSET_TAG = "car_ui_right_inset";
	private static final String TOP_INSET_TAG = "car_ui_top_inset";
	private static final String BOTTOM_INSET_TAG = "car_ui_bottom_inset";

	private final Activity mActivity;
	private final View mLeftInsetView;
	private final View mRightInsetView;
	private final View mTopInsetView;
	private final View mBottomInsetView;

	private boolean mInsetsDirty = true;
	@NonNull
	private Insets mInsets = new Insets();

	/**
	* Constructs an InsetsUpdater that calculates and dispatches insets to an {@link Activity}.
	*
	* @param activity The activity that is using base layouts
	* @param baseLayout The root view of the base layout
	* @param contentView The android.R.id.content View
	*/
	InsetsUpdater(Activity activity, View baseLayout, View contentView) {
	mActivity = activity;

	mLeftInsetView = baseLayout.findViewWithTag(LEFT_INSET_TAG);
	mRightInsetView = baseLayout.findViewWithTag(RIGHT_INSET_TAG);
	mTopInsetView = baseLayout.findViewWithTag(TOP_INSET_TAG);
	mBottomInsetView = baseLayout.findViewWithTag(BOTTOM_INSET_TAG);

	final View.OnLayoutChangeListener layoutChangeListener =
	(View v, int left, int top, int right, int bottom,
	int oldLeft, int oldTop, int oldRight, int oldBottom) -> {
	if (left != oldLeft \|\| top != oldTop
	\|\| right != oldRight \|\| bottom != oldBottom) {
	mInsetsDirty = true;
	}
	};

	if (mLeftInsetView != null) {
	mLeftInsetView.addOnLayoutChangeListener(layoutChangeListener);
	}
	if (mRightInsetView != null) {
	mRightInsetView.addOnLayoutChangeListener(layoutChangeListener);
	}
	if (mTopInsetView != null) {
	mTopInsetView.addOnLayoutChangeListener(layoutChangeListener);
	}
	if (mBottomInsetView != null) {
	mBottomInsetView.addOnLayoutChangeListener(layoutChangeListener);
	}
	contentView.addOnLayoutChangeListener(layoutChangeListener);
	}

	/**
	* Install a global layout listener, during which the insets will be recalculated and
	* dispatched.
	*/
	void installListeners() {
	// The global layout listener will run after all the individual layout change listeners
	// so that we only updateInsets once per layout, even if multiple inset views changed
	mActivity.getWindow().getDecorView().getViewTreeObserver()
	.addOnGlobalLayoutListener(this);
	}

	@NonNull
	Insets getInsets() {
	return mInsets;
	}

	/**
	* onGlobalLayout() should recalculate the amount of insets we need, and then dispatch them.
	*/
	@Override
	public void onGlobalLayout() {
	if (!mInsetsDirty) {
	return;
	}

	View content = mActivity.requireViewById(android.R.id.content);

	// Calculate how much each inset view overlays the content view
	int top, bottom, left, right;
	top = bottom = left = right = 0;
	if (mTopInsetView != null) {
	top = Math.max(0, getBottomOfView(mTopInsetView) - getTopOfView(content));
	}
	if (mBottomInsetView != null) {
	bottom = Math.max(0, getBottomOfView(content) - getTopOfView(mBottomInsetView));
	}
	if (mLeftInsetView != null) {
	left = Math.max(0, getRightOfView(mLeftInsetView) - getLeftOfView(content));
	}
	if (mRightInsetView != null) {
	right = Math.max(0, getRightOfView(content) - getLeftOfView(mRightInsetView));
	}
	Insets insets = new Insets(left, top, right, bottom);

	mInsetsDirty = false;
	if (!insets.equals(mInsets)) {
	mInsets = insets;
	dispatchNewInsets(insets);
	}
	}

	/**
	* Dispatch the new {@link Insets} to the {@link Activity} and all of its
	* {@link Fragment Fragments}. If none of those implement {@link InsetsChangedListener},
	* we will set the value of the insets as padding on the content view.
	*
	* @param insets The newly-changed insets.
	*/
	private void dispatchNewInsets(Insets insets) {
	boolean handled = false;
	if (mActivity instanceof InsetsChangedListener) {
	((InsetsChangedListener) mActivity).onCarUiInsetsChanged(insets);
	handled = true;
	}

	if (mActivity instanceof FragmentActivity) {
	for (Fragment fragment : ((FragmentActivity) mActivity).getSupportFragmentManager()
	.getFragments()) {
	if (fragment instanceof InsetsChangedListener) {
	((InsetsChangedListener) fragment).onCarUiInsetsChanged(insets);
	handled = true;
	}
	}
	}

	if (!handled) {
	mActivity.requireViewById(android.R.id.content).setPadding(
	insets.getLeft(), insets.getTop(), insets.getRight(), insets.getBottom());
	}
	}

	private static int getLeftOfView(View v) {
	int[] position = new int[2];
	v.getLocationOnScreen(position);
	return position[0];
	}

	private static int getRightOfView(View v) {
	int[] position = new int[2];
	v.getLocationOnScreen(position);
	return position[0] + v.getWidth();
	}

	private static int getTopOfView(View v) {
	int[] position = new int[2];
	v.getLocationOnScreen(position);
	return position[1];
	}

	private static int getBottomOfView(View v) {
	int[] position = new int[2];
	v.getLocationOnScreen(position);
	return position[1] + v.getHeight();
	}
	}
	}