Toggle.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.model;
import static java.util.Objects.requireNonNull;
import android.annotation.SuppressLint;
import android.os.Looper;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.car.app.annotations.CarProtocol;
import androidx.car.app.annotations.RequiresCarApi;
import androidx.car.app.annotations.KeepFields;
import java.util.Objects;
/**
* Represents a toggle that can have either a checked or unchecked state.
*
* <p>Toggles are allowed in Map and Pane templates from API >= 6.
* Old hosts may render bad UI if the toggles are added to hosts that don't support them.
*/
@CarProtocol
@KeepFields
public final class Toggle {
/** A listener for handling checked state change events. */
public interface OnCheckedChangeListener {
/** Notifies that the checked state has changed. */
void onCheckedChange(boolean isChecked);
}
@Nullable
private final OnCheckedChangeDelegate mOnCheckedChangeDelegate;
private final boolean mIsChecked;
private final boolean mIsEnabled;
/**
* Returns {@code true} if the toggle is checked.
*/
public boolean isChecked() {
return mIsChecked;
}
/**
* Returns {@code true} if the toggle is enabled.
*/
@RequiresCarApi(5)
public boolean isEnabled() {
return mIsEnabled;
}
/**
* Returns the {@link OnCheckedChangeDelegate} that is called when the checked state of
* the {@link Toggle} is changed.
*/
@NonNull
public OnCheckedChangeDelegate getOnCheckedChangeDelegate() {
return requireNonNull(mOnCheckedChangeDelegate);
}
@Override
@NonNull
public String toString() {
return "[ isChecked: " + mIsChecked + ", isEnabled: " + mIsEnabled + "]";
}
@Override
public int hashCode() {
return Objects.hash(mIsChecked, mIsEnabled);
}
@Override
public boolean equals(@Nullable Object other) {
if (this == other) {
return true;
}
if (!(other instanceof Toggle)) {
return false;
}
Toggle otherToggle = (Toggle) other;
// Don't compare listener.
return mIsChecked == otherToggle.mIsChecked && mIsEnabled == otherToggle.mIsEnabled;
}
Toggle(Builder builder) {
mIsChecked = builder.mIsChecked;
mIsEnabled = builder.mIsEnabled;
mOnCheckedChangeDelegate = builder.mOnCheckedChangeDelegate;
}
/** Constructs an empty instance, used by serialization code. */
private Toggle() {
mOnCheckedChangeDelegate = null;
mIsChecked = false;
mIsEnabled = true;
}
/** A builder of {@link Toggle}. */
public static final class Builder {
OnCheckedChangeDelegate mOnCheckedChangeDelegate;
boolean mIsChecked;
boolean mIsEnabled = true;
/**
* Sets the initial checked state for {@link Toggle}.
*
* <p>The default state of a {@link Toggle} is unchecked.
*/
@NonNull
public Builder setChecked(boolean checked) {
mIsChecked = checked;
return this;
}
/**
* Sets the initial enabled state for {@link Toggle}.
*
* <p>The default state of a {@link Toggle} is enabled.
*/
@NonNull
@RequiresCarApi(5)
public Builder setEnabled(boolean enabled) {
mIsEnabled = enabled;
return this;
}
/** Constructs the {@link Toggle} defined by this builder. */
@NonNull
public Toggle build() {
return new Toggle(this);
}
/**
* Returns a new instance of a {@link Builder} with the given
* {@link OnCheckedChangeListener}.
*
* <p>Note that the listener relates to UI events and will be executed on the main thread
* using {@link Looper#getMainLooper()}.
*
* @throws NullPointerException if {@code onCheckedChangeListener} is {@code null}
*/
@SuppressLint("ExecutorRegistration")
public Builder(@NonNull OnCheckedChangeListener onCheckedChangeListener) {
mOnCheckedChangeDelegate = OnCheckedChangeDelegateImpl.create(onCheckedChangeListener);
}
}
}