PlaceListNavigationTemplate.java
/*
* Copyright 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 androidx.car.app.navigation.model;
import static androidx.car.app.model.constraints.ActionsConstraints.ACTIONS_CONSTRAINTS_HEADER;
import static androidx.car.app.model.constraints.ActionsConstraints.ACTIONS_CONSTRAINTS_SIMPLE;
import static androidx.car.app.model.constraints.RowListConstraints.ROW_LIST_CONSTRAINTS_SIMPLE;
import static java.util.Objects.requireNonNull;
import androidx.annotation.Keep;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.car.app.Screen;
import androidx.car.app.SurfaceCallback;
import androidx.car.app.model.Action;
import androidx.car.app.model.ActionStrip;
import androidx.car.app.model.CarText;
import androidx.car.app.model.DistanceSpan;
import androidx.car.app.model.Item;
import androidx.car.app.model.ItemList;
import androidx.car.app.model.ModelUtils;
import androidx.car.app.model.Place;
import androidx.car.app.model.PlaceMarker;
import androidx.car.app.model.Row;
import androidx.car.app.model.Template;
import androidx.car.app.model.Toggle;
import java.util.Collections;
import java.util.List;
import java.util.Objects;
/**
* A template that supports showing a list of places alongside a custom drawn map.
*
* <p>The template itself does not expose a drawing surface. In order to draw on the canvas, use
* {@link androidx.car.app.AppManager#setSurfaceCallback(SurfaceCallback)}.
*
* <h4>Template Restrictions</h4>
*
* In regards to template refreshes, as described in {@link Screen#onGetTemplate()}, this template
* is considered a refresh of a previous one if:
*
* <ul>
* <li>The template title has not changed, and
* <li>The previous template is in a loading state (see {@link Builder#setLoading}, or the
* number of rows and the string contents (title, texts, not counting spans) of each row
* between the previous and new {@link ItemList}s have not changed.
* </ul>
*
* <p>In order to use this template your car app <b>MUST</b> declare that it uses the {@code
* androidx.car.app.NAVIGATION_TEMPLATES} permission in the manifest.
*/
public final class PlaceListNavigationTemplate implements Template {
@Keep
private final boolean mIsLoading;
@Keep
@Nullable
private final CarText mTitle;
@Keep
@Nullable
private final ItemList mItemList;
@Keep
@Nullable
private final Action mHeaderAction;
@Keep
@Nullable
private final ActionStrip mActionStrip;
/**
* Returns the title of the template or {@code null} if not set.
*
* @see Builder#setTitle(CharSequence)
*/
@Nullable
public CarText getTitle() {
return mTitle;
}
/**
* Returns the {@link Action} that is set to be displayed in the header of the template or
* {@code null} if not set.
*
* @see Builder#setHeaderAction(Action)
*/
@Nullable
public Action getHeaderAction() {
return mHeaderAction;
}
/**
* Returns the {@link ActionStrip} for this template or {@code null} if not set.
*
* @see Builder#setActionStrip(ActionStrip)
*/
@Nullable
public ActionStrip getActionStrip() {
return mActionStrip;
}
/**
* Returns whether the template is loading.
*
* @see Builder#setLoading(boolean)
*/
public boolean isLoading() {
return mIsLoading;
}
/**
* Returns the list of items to display alongside the map or {@code null} if the list is not
* set.
*
* @see Builder#setItemList(ItemList)
*/
@Nullable
public ItemList getItemList() {
return mItemList;
}
@NonNull
@Override
public String toString() {
return "PlaceListNavigationTemplate";
}
@Override
public int hashCode() {
return Objects.hash(mTitle, mIsLoading, mItemList, mHeaderAction, mActionStrip);
}
@Override
public boolean equals(@Nullable Object other) {
if (this == other) {
return true;
}
if (!(other instanceof PlaceListNavigationTemplate)) {
return false;
}
PlaceListNavigationTemplate otherTemplate = (PlaceListNavigationTemplate) other;
return mIsLoading == otherTemplate.mIsLoading
&& Objects.equals(mTitle, otherTemplate.mTitle)
&& Objects.equals(mItemList, otherTemplate.mItemList)
&& Objects.equals(mHeaderAction, otherTemplate.mHeaderAction)
&& Objects.equals(mActionStrip, otherTemplate.mActionStrip);
}
PlaceListNavigationTemplate(Builder builder) {
mTitle = builder.mTitle;
mIsLoading = builder.mIsLoading;
mItemList = builder.mItemList;
mHeaderAction = builder.mHeaderAction;
mActionStrip = builder.mActionStrip;
}
/** Constructs an empty instance, used by serialization code. */
private PlaceListNavigationTemplate() {
mTitle = null;
mIsLoading = false;
mItemList = null;
mHeaderAction = null;
mActionStrip = null;
}
/** A builder of {@link PlaceListNavigationTemplate}. */
public static final class Builder {
@Nullable
CarText mTitle;
boolean mIsLoading;
@Nullable
ItemList mItemList;
@Nullable
Action mHeaderAction;
@Nullable
ActionStrip mActionStrip;
/**
* Sets the title of the template.
*
* <p>Unless set with this method, the template will not have a title.
*
* <p>Spans are not supported in the input string.
*
* @throws NullPointerException if {@code title} is null
* @see CarText
*/
@NonNull
public Builder setTitle(@NonNull CharSequence title) {
mTitle = CarText.create(requireNonNull(title));
return this;
}
/**
* Sets whether the template is in a loading state.
*
* <p>If set to {@code true}, the UI will show a loading indicator where the list content
* would be otherwise. The caller is expected to call
* {@link androidx.car.app.Screen#invalidate()} and send the new template content to the
* host once the data is ready. If set to {@code false}, the UI shows the {@link ItemList}
* contents added via {@link #setItemList}.
*/
@NonNull
public Builder setLoading(boolean isLoading) {
mIsLoading = isLoading;
return this;
}
/**
* Sets the {@link Action} that will be displayed in the header of the template.
*
* <p>Unless set with this method, the template will not have a header action.
*
* <h4>Requirements</h4>
*
* This template only supports either one of {@link Action#APP_ICON} and
* {@link Action#BACK} as a header {@link Action}.
*
* @throws IllegalArgumentException if {@code headerAction} does not meet the template's
* requirements
* @throws NullPointerException if {@code headerAction} is {@code null}
*/
@NonNull
public Builder setHeaderAction(@NonNull Action headerAction) {
ACTIONS_CONSTRAINTS_HEADER.validateOrThrow(
Collections.singletonList(requireNonNull(headerAction)));
mHeaderAction = headerAction;
return this;
}
/**
* Sets an {@link ItemList} to show in the list view along with the map.
*
* <p>To show a marker corresponding to a point of interest represented by a row, set the
* {@link Place} instance via {@link Row.Builder#setMetadata}. The host will render the
* {@link PlaceMarker} in the list view as the row become visible. The app should
* synchronize with the list's behavior by rendering the same marker on the map surface.
*
* <h4>Requirements</h4>
*
* This template allows up to 6 {@link Row}s in the {@link ItemList}. The host will
* ignore any items over that limit. The list itself cannot be selectable as set via {@link
* ItemList.Builder#setOnSelectedListener}. Each {@link Row} can add up to 2 lines of texts
* via {@link Row.Builder#addText} and cannot contain a {@link Toggle}.
*
* <p>Images of type {@link Row#IMAGE_TYPE_LARGE} are not allowed in this template.
*
* <p>Rows are not allowed to have both and an image and a place marker.
*
* <p>All non-browsable rows must have a {@link DistanceSpan} attached to either its
* title or texts, to indicate the distance of the point of interest from the current
* location. Where in the title or text the span is attached to is up to the app.
*
* @throws IllegalArgumentException if {@code itemList} does not meet the template's
* requirements
* @throws NullPointerException if {@code itemList} is {@code null}
*/
@NonNull
public Builder setItemList(@NonNull ItemList itemList) {
List<Item> items = requireNonNull(itemList).getItems();
ROW_LIST_CONSTRAINTS_SIMPLE.validateOrThrow(itemList);
ModelUtils.validateAllNonBrowsableRowsHaveDistance(items);
ModelUtils.validateAllRowsHaveOnlySmallImages(items);
ModelUtils.validateNoRowsHaveBothMarkersAndImages(items);
mItemList = itemList;
return this;
}
/**
* Sets the {@link ActionStrip} for this template, or {@code null} to not display an {@link
* ActionStrip}.
*
* <p>Unless set with this method, the template will not have an action strip.
*
* <h4>Requirements</h4>
*
* This template allows up to 2 {@link Action}s in its {@link ActionStrip}. Of the 2 allowed
* {@link Action}s, one of them can contain a title as set via
* {@link Action.Builder#setTitle}. Otherwise, only {@link Action}s with icons are allowed.
*
* @throws IllegalArgumentException if {@code actionStrip} does not meet the requirements
* @throws NullPointerException if {@code actionStrip} is {@code null}
*/
@NonNull
public Builder setActionStrip(@NonNull ActionStrip actionStrip) {
ACTIONS_CONSTRAINTS_SIMPLE.validateOrThrow(requireNonNull(actionStrip).getActions());
mActionStrip = actionStrip;
return this;
}
/**
* Constructs the template defined by this builder.
*
* <h4>Requirements</h4>
*
* Either a header {@link Action} or title must be set on the template.
*
* @throws IllegalArgumentException if the template is in a loading state but the list is
* set, or vice versa
* @throws IllegalStateException if the template does not have either a title or header
* {@link Action} set
*/
@NonNull
public PlaceListNavigationTemplate build() {
boolean hasList = mItemList != null;
if (mIsLoading == hasList) {
throw new IllegalArgumentException(
"Template is in a loading state but a list is set, or vice versa");
}
if (CarText.isNullOrEmpty(mTitle) && mHeaderAction == null) {
throw new IllegalStateException("Either the title or header action must be set");
}
return new PlaceListNavigationTemplate(this);
}
/** Constructs an empty {@link Builder} instance. */
public Builder() {
}
}
}