content: /*
   * Copyright (C) 2006 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 android.widget;
  
  import android.annotation.IdRes;
  import android.annotation.NonNull;
  import android.annotation.UnsupportedAppUsage;
  import android.content.Context;
  import android.content.res.TypedArray;
  import android.util.AttributeSet;
  import android.util.Log;
  import android.view.View;
  import android.view.ViewGroup;
  import android.view.ViewStructure;
  import android.view.autofill.AutofillManager;
  import android.view.autofill.AutofillValue;
  
  import com.android.internal.R;
  
  
  /**
   * <p>This class is used to create a multiple-exclusion scope for a set of radio
   * buttons. Checking one radio button that belongs to a radio group unchecks
   * any previously checked radio button within the same group.</p>
   *
   * <p>Intially, all of the radio buttons are unchecked. While it is not possible
   * to uncheck a particular radio button, the radio group can be cleared to
   * remove the checked state.</p>
   *
   * <p>The selection is identified by the unique id of the radio button as defined
   * in the XML layout file.</p>
   *
   * <p><strong>XML Attributes</strong></p>
   * <p>See {@link android.R.styleable#RadioGroup RadioGroup Attributes},
   * {@link android.R.styleable#LinearLayout LinearLayout Attributes},
   * {@link android.R.styleable#ViewGroup ViewGroup Attributes},
   * {@link android.R.styleable#View View Attributes}</p>
   * <p>Also see
   * {@link android.widget.LinearLayout.LayoutParams LinearLayout.LayoutParams}
   * for layout attributes.</p>
   *
   * @see RadioButton
   *
   */
  public class RadioGroup extends LinearLayout {
      private static final String LOG_TAG = RadioGroup.class.getSimpleName();
  
      // holds the checked id; the selection is empty by default
      private int mCheckedId = -1;
      // tracks children radio buttons checked state
      @UnsupportedAppUsage
      private CompoundButton.OnCheckedChangeListener mChildOnCheckedChangeListener;
      // when true, mOnCheckedChangeListener discards events
      private boolean mProtectFromCheckedChange = false;
      @UnsupportedAppUsage
      private OnCheckedChangeListener mOnCheckedChangeListener;
      private PassThroughHierarchyChangeListener mPassThroughListener;
  
      // Indicates whether the child was set from resources or dynamically, so it can be used
      // to sanitize autofill requests.
      private int mInitialCheckedId = View.NO_ID;
  
      /**
       * {@inheritDoc}
       */
      public RadioGroup(Context context) {
          super(context);
          setOrientation(VERTICAL);
          init();
      }
  
      /**
       * {@inheritDoc}
       */
      public RadioGroup(Context context, AttributeSet attrs) {
          super(context, attrs);
  
          // RadioGroup is important by default, unless app developer overrode attribute.
          if (getImportantForAutofill() == IMPORTANT_FOR_AUTOFILL_AUTO) {
              setImportantForAutofill(IMPORTANT_FOR_AUTOFILL_YES);
          }
  
          // retrieve selected radio button as requested by the user in the
          // XML layout file
          TypedArray attributes = context.obtainStyledAttributes(
                  attrs, com.android.internal.R.styleable.RadioGroup, com.android.internal.R.attr.radioButtonStyle, 0);
          saveAttributeDataForStyleable(context, com.android.internal.R.styleable.RadioGroup,
                  attrs, attributes, com.android.internal.R.attr.radioButtonStyle, 0);
  
          int value = attributes.getResourceId(R.styleable.RadioGroup_checkedButton, View.NO_ID);
          if (value != View.NO_ID) {
              mCheckedId = value;
              mInitialCheckedId = value;
          }
          final int index = attributes.getInt(com.android.internal.R.styleable.RadioGroup_orientation, VERTICAL);
          setOrientation(index);
  
          attributes.recycle();
          init();
      }
  
      private void init() {
          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) {
          boolean changed = id != mCheckedId;
          mCheckedId = id;
  
          if (mOnCheckedChangeListener != null) {
              mOnCheckedChangeListener.onCheckedChanged(this, mCheckedId);
          }
          if (changed) {
              final AutofillManager afm = mContext.getSystemService(AutofillManager.class);
              if (afm != null) {
                  afm.notifyValueChanged(this);
              }
          }
      }
  
      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()
       *
       * @attr ref android.R.styleable#RadioGroup_checkedButton
       */
      @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;
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public LayoutParams generateLayoutParams(AttributeSet attrs) {
          return new RadioGroup.LayoutParams(getContext(), attrs);
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      protected boolean checkLayoutParams(ViewGroup.LayoutParams p) {
          return p instanceof RadioGroup.LayoutParams;
      }
  
      @Override
      protected LinearLayout.LayoutParams generateDefaultLayoutParams() {
          return new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
      }
  
      @Override
      public CharSequence getAccessibilityClassName() {
          return RadioGroup.class.getName();
      }
  
      /**
       * <p>This set of layout parameters defaults the width and the height of
       * the children to {@link #WRAP_CONTENT} when they are not specified in the
       * XML file. Otherwise, this class ussed the value read from the XML file.</p>
       *
       * <p>See
       * {@link android.R.styleable#LinearLayout_Layout LinearLayout Attributes}
       * for a list of all child view attributes that this class supports.</p>
       *
       */
      public static class LayoutParams extends LinearLayout.LayoutParams {
          /**
           * {@inheritDoc}
           */
          public LayoutParams(Context c, AttributeSet attrs) {
              super(c, attrs);
          }
  
          /**
           * {@inheritDoc}
           */
          public LayoutParams(int w, int h) {
              super(w, h);
          }
  
          /**
           * {@inheritDoc}
           */
          public LayoutParams(int w, int h, float initWeight) {
              super(w, h, initWeight);
          }
  
          /**
           * {@inheritDoc}
           */
          public LayoutParams(ViewGroup.LayoutParams p) {
              super(p);
          }
  
          /**
           * {@inheritDoc}
           */
          public LayoutParams(MarginLayoutParams source) {
              super(source);
          }
  
          /**
           * <p>Fixes the child's width to
           * {@link android.view.ViewGroup.LayoutParams#WRAP_CONTENT} and the child's
           * height to  {@link android.view.ViewGroup.LayoutParams#WRAP_CONTENT}
           * when not specified in the XML file.</p>
           *
           * @param a the styled attributes set
           * @param widthAttr the width attribute to fetch
           * @param heightAttr the height attribute to fetch
           */
          @Override
          protected void setBaseAttributes(TypedArray a,
                  int widthAttr, int heightAttr) {
  
              if (a.hasValue(widthAttr)) {
                  width = a.getLayoutDimension(widthAttr, "layout_width");
              } else {
                  width = WRAP_CONTENT;
              }
  
              if (a.hasValue(heightAttr)) {
                  height = a.getLayoutDimension(heightAttr, "layout_height");
              } else {
                  height = WRAP_CONTENT;
              }
          }
      }
  
      /**
       * <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
           */
          public void onCheckedChanged(RadioGroup 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 == RadioGroup.this && child instanceof RadioButton) {
                  int id = child.getId();
                  // generates an id if it's missing
                  if (id == View.NO_ID) {
                      id = View.generateViewId();
                      child.setId(id);
                  }
                  ((RadioButton) child).setOnCheckedChangeWidgetListener(
                          mChildOnCheckedChangeListener);
              }
  
              if (mOnHierarchyChangeListener != null) {
                  mOnHierarchyChangeListener.onChildViewAdded(parent, child);
              }
          }
  
          /**
           * {@inheritDoc}
           */
          @Override
          public void onChildViewRemoved(View parent, View child) {
              if (parent == RadioGroup.this && child instanceof RadioButton) {
                  ((RadioButton) child).setOnCheckedChangeWidgetListener(null);
              }
  
              if (mOnHierarchyChangeListener != null) {
                  mOnHierarchyChangeListener.onChildViewRemoved(parent, child);
              }
          }
      }
  
      /** @hide */
      @Override
      protected void onProvideStructure(@NonNull ViewStructure structure,
              @ViewStructureType int viewFor, int flags) {
          super.onProvideStructure(structure, viewFor, flags);
  
          if (viewFor == VIEW_STRUCTURE_FOR_AUTOFILL) {
              structure.setDataIsSensitive(mCheckedId != mInitialCheckedId);
          }
      }
  
      @Override
      public void autofill(AutofillValue value) {
          if (!isEnabled()) return;
  
          if (!value.isList()) {
              Log.w(LOG_TAG, value + " could not be autofilled into " + this);
              return;
          }
  
          final int index = value.getListValue();
          final View child = getChildAt(index);
          if (child == null) {
              Log.w(VIEW_LOG_TAG, "RadioGroup.autoFill(): no child with index " + index);
              return;
          }
  
          check(child.getId());
      }
  
      @Override
      public @AutofillType int getAutofillType() {
          return isEnabled() ? AUTOFILL_TYPE_LIST : AUTOFILL_TYPE_NONE;
      }
  
      @Override
      public AutofillValue getAutofillValue() {
          if (!isEnabled()) return null;
  
          final int count = getChildCount();
          for (int i = 0; i < count; i++) {
              final View child = getChildAt(i);
              if (child.getId() == mCheckedId) {
                  return AutofillValue.forList(i);
              }
          }
          return null;
      }
  }
  