/* * Copyright 2016 Hippo Seven * * 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.hippo.widget; import android.content.Context; import android.content.res.TypedArray; import android.util.AttributeSet; import android.view.View; import android.view.ViewGroup; import android.widget.CompoundButton; import android.widget.RadioButton; import androidx.annotation.IdRes; import com.hippo.yorozuya.ViewUtils; public class RadioGridGroup extends SimpleGridLayout { private static final int[] RADIO_ATTRS = new int[] { android.R.attr.checkedButton }; // holds the checked id; the selection is empty by default private int mCheckedId = -1; // tracks children radio buttons checked state private CompoundButton.OnCheckedChangeListener mChildOnCheckedChangeListener; // when true, mOnCheckedChangeListener discards events private boolean mProtectFromCheckedChange = false; private OnCheckedChangeListener mOnCheckedChangeListener; private PassThroughHierarchyChangeListener mPassThroughListener; public RadioGridGroup(Context context, AttributeSet attrs) { super(context, attrs); init(context, attrs); } public RadioGridGroup(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); init(context, attrs); } private void init(Context context, AttributeSet attrs) { final TypedArray a = context.obtainStyledAttributes(attrs, RADIO_ATTRS); int value = a.getResourceId(0, View.NO_ID); if (value != View.NO_ID) { mCheckedId = value; } a.recycle(); mChildOnCheckedChangeListener = new CheckedStateTracker(); mPassThroughListener = new PassThroughHierarchyChangeListener(); super.setOnHierarchyChangeListener(mPassThroughListener); } /** * {@inheritDoc} */ @Override public void setOnHierarchyChangeListener(OnHierarchyChangeListener listener) { // the user listener is delegated to our pass-through listener mPassThroughListener.mOnHierarchyChangeListener = listener; } /** * {@inheritDoc} */ @Override protected void onFinishInflate() { super.onFinishInflate(); // checks the appropriate radio button as requested in the XML file if (mCheckedId != -1) { mProtectFromCheckedChange = true; setCheckedStateForView(mCheckedId, true); mProtectFromCheckedChange = false; setCheckedId(mCheckedId); } } @Override public void addView(View child, int index, ViewGroup.LayoutParams params) { if (child instanceof RadioButton) { final RadioButton button = (RadioButton) child; if (button.isChecked()) { mProtectFromCheckedChange = true; if (mCheckedId != -1) { setCheckedStateForView(mCheckedId, false); } mProtectFromCheckedChange = false; setCheckedId(button.getId()); } } super.addView(child, index, params); } /** * <p>Sets the selection to the radio button whose identifier is passed in * parameter. Using -1 as the selection identifier clears the selection; * such an operation is equivalent to invoking {@link #clearCheck()}.</p> * * @param id the unique id of the radio button to select in this group * * @see #getCheckedRadioButtonId() * @see #clearCheck() */ public void check(@IdRes int id) { // don't even bother if (id != -1 && (id == mCheckedId)) { return; } if (mCheckedId != -1) { setCheckedStateForView(mCheckedId, false); } if (id != -1) { setCheckedStateForView(id, true); } setCheckedId(id); } private void setCheckedId(@IdRes int id) { mCheckedId = id; if (mOnCheckedChangeListener != null) { mOnCheckedChangeListener.onCheckedChanged(this, mCheckedId); } } private void setCheckedStateForView(int viewId, boolean checked) { View checkedView = findViewById(viewId); if (checkedView != null && checkedView instanceof RadioButton) { ((RadioButton) checkedView).setChecked(checked); } } /** * <p>Returns the identifier of the selected radio button in this group. * Upon empty selection, the returned value is -1.</p> * * @return the unique id of the selected radio button in this group * * @see #check(int) * @see #clearCheck() */ @IdRes public int getCheckedRadioButtonId() { return mCheckedId; } /** * <p>Clears the selection. When the selection is cleared, no radio button * in this group is selected and {@link #getCheckedRadioButtonId()} returns * null.</p> * * @see #check(int) * @see #getCheckedRadioButtonId() */ public void clearCheck() { check(-1); } /** * <p>Register a callback to be invoked when the checked radio button * changes in this group.</p> * * @param listener the callback to call on checked state change */ public void setOnCheckedChangeListener(OnCheckedChangeListener listener) { mOnCheckedChangeListener = listener; } /** * <p>Interface definition for a callback to be invoked when the checked * radio button changed in this group.</p> */ public interface OnCheckedChangeListener { /** * <p>Called when the checked radio button has changed. When the * selection is cleared, checkedId is -1.</p> * * @param group the group in which the checked radio button has changed * @param checkedId the unique identifier of the newly checked radio button */ void onCheckedChanged(RadioGridGroup group, @IdRes int checkedId); } private class CheckedStateTracker implements CompoundButton.OnCheckedChangeListener { @Override public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { // prevents from infinite recursion if (mProtectFromCheckedChange) { return; } mProtectFromCheckedChange = true; if (mCheckedId != -1) { setCheckedStateForView(mCheckedId, false); } mProtectFromCheckedChange = false; int id = buttonView.getId(); setCheckedId(id); } } /** * <p>A pass-through listener acts upon the events and dispatches them * to another listener. This allows the table layout to set its own internal * hierarchy change listener without preventing the user to setup his.</p> */ private class PassThroughHierarchyChangeListener implements ViewGroup.OnHierarchyChangeListener { private ViewGroup.OnHierarchyChangeListener mOnHierarchyChangeListener; /** * {@inheritDoc} */ @Override public void onChildViewAdded(View parent, View child) { if (parent == RadioGridGroup.this && child instanceof RadioButton) { int id = child.getId(); // generates an id if it's missing if (id == View.NO_ID) { id = ViewUtils.generateViewId(); child.setId(id); } ((RadioButton) child).setOnCheckedChangeListener( mChildOnCheckedChangeListener); } if (mOnHierarchyChangeListener != null) { mOnHierarchyChangeListener.onChildViewAdded(parent, child); } } /** * {@inheritDoc} */ @Override public void onChildViewRemoved(View parent, View child) { if (parent == RadioGridGroup.this && child instanceof RadioButton) { ((RadioButton) child).setOnCheckedChangeListener(null); } if (mOnHierarchyChangeListener != null) { mOnHierarchyChangeListener.onChildViewRemoved(parent, child); } } } }