core/java/android/widget/CompoundButton.java - platform/frameworks/base - Git at Google

 /*
  * Copyright (C) 2007 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 com.android.internal.R;

 import android.content.Context;
 import android.content.res.TypedArray;
 import android.graphics.Canvas;
 import android.graphics.drawable.Drawable;
 import android.os.Parcel;
 import android.os.Parcelable;
 import android.util.AttributeSet;
 import android.view.Gravity;


 /**
  * <p>
  * A button with two states, checked and unchecked. When the button is pressed
  * or clicked, the state changes automatically.
  * </p>
  *
  * <p><strong>XML attributes</strong></p>
  * <p>
  * See {@link android.R.styleable#CompoundButton
  * CompoundButton Attributes}, {@link android.R.styleable#Button Button
  * Attributes}, {@link android.R.styleable#TextView TextView Attributes}, {@link
  * android.R.styleable#View View Attributes}
  * </p>
  */
 public abstract class CompoundButton extends Button implements Checkable {
     private boolean mChecked;
     private int mButtonResource;
     private boolean mBroadcasting;
     private Drawable mButtonDrawable;
     private OnCheckedChangeListener mOnCheckedChangeListener;
     private OnCheckedChangeListener mOnCheckedChangeWidgetListener;

     private static final int[] CHECKED_STATE_SET = {
         R.attr.state_checked
     };

     public CompoundButton(Context context) {
         this(context, null);
     }

     public CompoundButton(Context context, AttributeSet attrs) {
         this(context, attrs, 0);
     }

     public CompoundButton(Context context, AttributeSet attrs, int defStyle) {
         super(context, attrs, defStyle);

         TypedArray a =
                 context.obtainStyledAttributes(
                         attrs, com.android.internal.R.styleable.CompoundButton, defStyle, 0);

         Drawable d = a.getDrawable(com.android.internal.R.styleable.CompoundButton_button);
         if (d != null) {
             setButtonDrawable(d);
         }

         boolean checked = a
                 .getBoolean(com.android.internal.R.styleable.CompoundButton_checked, false);
         setChecked(checked);

         a.recycle();
     }

     public void toggle() {
         setChecked(!mChecked);
     }

     @Override
     public boolean performClick() {
         /*
          * XXX: These are tiny, need some surrounding 'expanded touch area',
          * which will need to be implemented in Button if we only override
          * performClick()
          */

         /* When clicked, toggle the state */
         toggle();
         return super.performClick();
     }

     public boolean isChecked() {
         return mChecked;
     }

     /**
      * <p>Changes the checked state of this button.</p>
      *
      * @param checked true to check the button, false to uncheck it
      */
     public void setChecked(boolean checked) {
         if (mChecked != checked) {
             mChecked = checked;
             refreshDrawableState();

             // Avoid infinite recursions if setChecked() is called from a listener
             if (mBroadcasting) {
                 return;
             }

             mBroadcasting = true;
             if (mOnCheckedChangeListener != null) {
                 mOnCheckedChangeListener.onCheckedChanged(this, mChecked);
             }
             if (mOnCheckedChangeWidgetListener != null) {
                 mOnCheckedChangeWidgetListener.onCheckedChanged(this, mChecked);
             }
             mBroadcasting = false;
         }
     }

     /**
      * Register a callback to be invoked when the checked state of this button
      * changes.
      *
      * @param listener the callback to call on checked state change
      */
     public void setOnCheckedChangeListener(OnCheckedChangeListener listener) {
         mOnCheckedChangeListener = listener;
     }

     /**
      * Register a callback to be invoked when the checked state of this button
      * changes. This callback is used for internal purpose only.
      *
      * @param listener the callback to call on checked state change
      * @hide
      */
     void setOnCheckedChangeWidgetListener(OnCheckedChangeListener listener) {
         mOnCheckedChangeWidgetListener = listener;
     }

     /**
      * Interface definition for a callback to be invoked when the checked state
      * of a compound button changed.
      */
     public static interface OnCheckedChangeListener {
         /**
          * Called when the checked state of a compound button has changed.
          *
          * @param buttonView The compound button view whose state has changed.
          * @param isChecked  The new checked state of buttonView.
          */
         void onCheckedChanged(CompoundButton buttonView, boolean isChecked);
     }

     /**
      * Set the background to a given Drawable, identified by its resource id.
      *
      * @param resid the resource id of the drawable to use as the background
      */
     public void setButtonDrawable(int resid) {
         if (resid != 0 && resid == mButtonResource) {
             return;
         }

         mButtonResource = resid;

         Drawable d = null;
         if (mButtonResource != 0) {
             d = getResources().getDrawable(mButtonResource);
         }
         setButtonDrawable(d);
     }

     /**
      * Set the background to a given Drawable
      *
      * @param d The Drawable to use as the background
      */
     public void setButtonDrawable(Drawable d) {
         if (d != null) {
             if (mButtonDrawable != null) {
                 mButtonDrawable.setCallback(null);
                 unscheduleDrawable(mButtonDrawable);
             }
             d.setCallback(this);
             d.setState(getDrawableState());
             d.setVisible(getVisibility() == VISIBLE, false);
             mButtonDrawable = d;
             mButtonDrawable.setState(null);
             setMinHeight(mButtonDrawable.getIntrinsicHeight());
         }

         refreshDrawableState();
     }

     @Override
     protected void onDraw(Canvas canvas) {
         super.onDraw(canvas);

         final Drawable buttonDrawable = mButtonDrawable;
         if (buttonDrawable != null) {
             final int verticalGravity = getGravity() & Gravity.VERTICAL_GRAVITY_MASK;
             final int height = buttonDrawable.getIntrinsicHeight();

             int y = 0;

             switch (verticalGravity) {
                 case Gravity.BOTTOM:
                     y = getHeight() - height;
                     break;
                 case Gravity.CENTER_VERTICAL:
                     y = (getHeight() - height) / 2;
                     break;
             }

             buttonDrawable.setBounds(0, y, buttonDrawable.getIntrinsicWidth(), y + height);
             buttonDrawable.draw(canvas);
         }
     }

     @Override
     protected int[] onCreateDrawableState(int extraSpace) {
         final int[] drawableState = super.onCreateDrawableState(extraSpace + 1);
         if (isChecked()) {
             mergeDrawableStates(drawableState, CHECKED_STATE_SET);
         }
         return drawableState;
     }

     @Override
     protected void drawableStateChanged() {
         super.drawableStateChanged();

         if (mButtonDrawable != null) {
             int[] myDrawableState = getDrawableState();

             // Set the state of the Drawable
             mButtonDrawable.setState(myDrawableState);

             invalidate();
         }
     }

     @Override
     protected boolean verifyDrawable(Drawable who) {
         return super.verifyDrawable(who) || who == mButtonDrawable;
     }

     static class SavedState extends BaseSavedState {
         boolean checked;

         /**
          * Constructor called from {@link CompoundButton#onSaveInstanceState()}
          */
         SavedState(Parcelable superState) {
             super(superState);
         }

         /**
          * Constructor called from {@link #CREATOR}
          */
         private SavedState(Parcel in) {
             super(in);
             checked = (Boolean)in.readValue(null);
         }

         @Override
         public void writeToParcel(Parcel out, int flags) {
             super.writeToParcel(out, flags);
             out.writeValue(checked);
         }

         @Override
         public String toString() {
             return "CompoundButton.SavedState{"
                     + Integer.toHexString(System.identityHashCode(this))
                     + " checked=" + checked + "}";
         }

         public static final Parcelable.Creator<SavedState> CREATOR
                 = new Parcelable.Creator<SavedState>() {
             public SavedState createFromParcel(Parcel in) {
                 return new SavedState(in);
             }

             public SavedState[] newArray(int size) {
                 return new SavedState[size];
             }
         };
     }

     @Override
     public Parcelable onSaveInstanceState() {
         // Force our ancestor class to save its state
         setFreezesText(true);
         Parcelable superState = super.onSaveInstanceState();

         SavedState ss = new SavedState(superState);

         ss.checked = isChecked();
         return ss;
     }

     @Override
     public void onRestoreInstanceState(Parcelable state) {
         SavedState ss = (SavedState) state;

         super.onRestoreInstanceState(ss.getSuperState());
         setChecked(ss.checked);
         requestLayout();
     }
 }
	/*
	* Copyright (C) 2007 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 com.android.internal.R;

	import android.content.Context;
	import android.content.res.TypedArray;
	import android.graphics.Canvas;
	import android.graphics.drawable.Drawable;
	import android.os.Parcel;
	import android.os.Parcelable;
	import android.util.AttributeSet;
	import android.view.Gravity;


	/**
	* <p>
	* A button with two states, checked and unchecked. When the button is pressed
	* or clicked, the state changes automatically.
	* </p>
	*
	* <p><strong>XML attributes</strong></p>
	* <p>
	* See {@link android.R.styleable#CompoundButton
	* CompoundButton Attributes}, {@link android.R.styleable#Button Button
	* Attributes}, {@link android.R.styleable#TextView TextView Attributes}, {@link
	* android.R.styleable#View View Attributes}
	* </p>
	*/
	public abstract class CompoundButton extends Button implements Checkable {
	private boolean mChecked;
	private int mButtonResource;
	private boolean mBroadcasting;
	private Drawable mButtonDrawable;
	private OnCheckedChangeListener mOnCheckedChangeListener;
	private OnCheckedChangeListener mOnCheckedChangeWidgetListener;

	private static final int[] CHECKED_STATE_SET = {
	R.attr.state_checked
	};

	public CompoundButton(Context context) {
	this(context, null);
	}

	public CompoundButton(Context context, AttributeSet attrs) {
	this(context, attrs, 0);
	}

	public CompoundButton(Context context, AttributeSet attrs, int defStyle) {
	super(context, attrs, defStyle);

	TypedArray a =
	context.obtainStyledAttributes(
	attrs, com.android.internal.R.styleable.CompoundButton, defStyle, 0);

	Drawable d = a.getDrawable(com.android.internal.R.styleable.CompoundButton_button);
	if (d != null) {
	setButtonDrawable(d);
	}

	boolean checked = a
	.getBoolean(com.android.internal.R.styleable.CompoundButton_checked, false);
	setChecked(checked);

	a.recycle();
	}

	public void toggle() {
	setChecked(!mChecked);
	}

	@Override
	public boolean performClick() {
	/*
	* XXX: These are tiny, need some surrounding 'expanded touch area',
	* which will need to be implemented in Button if we only override
	* performClick()
	*/

	/* When clicked, toggle the state */
	toggle();
	return super.performClick();
	}

	public boolean isChecked() {
	return mChecked;
	}

	/**
	* <p>Changes the checked state of this button.</p>
	*
	* @param checked true to check the button, false to uncheck it
	*/
	public void setChecked(boolean checked) {
	if (mChecked != checked) {
	mChecked = checked;
	refreshDrawableState();

	// Avoid infinite recursions if setChecked() is called from a listener
	if (mBroadcasting) {
	return;
	}

	mBroadcasting = true;
	if (mOnCheckedChangeListener != null) {
	mOnCheckedChangeListener.onCheckedChanged(this, mChecked);
	}
	if (mOnCheckedChangeWidgetListener != null) {
	mOnCheckedChangeWidgetListener.onCheckedChanged(this, mChecked);
	}
	mBroadcasting = false;
	}
	}

	/**
	* Register a callback to be invoked when the checked state of this button
	* changes.
	*
	* @param listener the callback to call on checked state change
	*/
	public void setOnCheckedChangeListener(OnCheckedChangeListener listener) {
	mOnCheckedChangeListener = listener;
	}

	/**
	* Register a callback to be invoked when the checked state of this button
	* changes. This callback is used for internal purpose only.
	*
	* @param listener the callback to call on checked state change
	* @hide
	*/
	void setOnCheckedChangeWidgetListener(OnCheckedChangeListener listener) {
	mOnCheckedChangeWidgetListener = listener;
	}

	/**
	* Interface definition for a callback to be invoked when the checked state
	* of a compound button changed.
	*/
	public static interface OnCheckedChangeListener {
	/**
	* Called when the checked state of a compound button has changed.
	*
	* @param buttonView The compound button view whose state has changed.
	* @param isChecked The new checked state of buttonView.
	*/
	void onCheckedChanged(CompoundButton buttonView, boolean isChecked);
	}

	/**
	* Set the background to a given Drawable, identified by its resource id.
	*
	* @param resid the resource id of the drawable to use as the background
	*/
	public void setButtonDrawable(int resid) {
	if (resid != 0 && resid == mButtonResource) {
	return;
	}

	mButtonResource = resid;

	Drawable d = null;
	if (mButtonResource != 0) {
	d = getResources().getDrawable(mButtonResource);
	}
	setButtonDrawable(d);
	}

	/**
	* Set the background to a given Drawable
	*
	* @param d The Drawable to use as the background
	*/
	public void setButtonDrawable(Drawable d) {
	if (d != null) {
	if (mButtonDrawable != null) {
	mButtonDrawable.setCallback(null);
	unscheduleDrawable(mButtonDrawable);
	}
	d.setCallback(this);
	d.setState(getDrawableState());
	d.setVisible(getVisibility() == VISIBLE, false);
	mButtonDrawable = d;
	mButtonDrawable.setState(null);
	setMinHeight(mButtonDrawable.getIntrinsicHeight());
	}

	refreshDrawableState();
	}

	@Override
	protected void onDraw(Canvas canvas) {
	super.onDraw(canvas);

	final Drawable buttonDrawable = mButtonDrawable;
	if (buttonDrawable != null) {
	final int verticalGravity = getGravity() & Gravity.VERTICAL_GRAVITY_MASK;
	final int height = buttonDrawable.getIntrinsicHeight();

	int y = 0;

	switch (verticalGravity) {
	case Gravity.BOTTOM:
	y = getHeight() - height;
	break;
	case Gravity.CENTER_VERTICAL:
	y = (getHeight() - height) / 2;
	break;
	}

	buttonDrawable.setBounds(0, y, buttonDrawable.getIntrinsicWidth(), y + height);
	buttonDrawable.draw(canvas);
	}
	}

	@Override
	protected int[] onCreateDrawableState(int extraSpace) {
	final int[] drawableState = super.onCreateDrawableState(extraSpace + 1);
	if (isChecked()) {
	mergeDrawableStates(drawableState, CHECKED_STATE_SET);
	}
	return drawableState;
	}

	@Override
	protected void drawableStateChanged() {
	super.drawableStateChanged();

	if (mButtonDrawable != null) {
	int[] myDrawableState = getDrawableState();

	// Set the state of the Drawable
	mButtonDrawable.setState(myDrawableState);

	invalidate();
	}
	}

	@Override
	protected boolean verifyDrawable(Drawable who) {
	return super.verifyDrawable(who) \|\| who == mButtonDrawable;
	}

	static class SavedState extends BaseSavedState {
	boolean checked;

	/**
	* Constructor called from {@link CompoundButton#onSaveInstanceState()}
	*/
	SavedState(Parcelable superState) {
	super(superState);
	}

	/**
	* Constructor called from {@link #CREATOR}
	*/
	private SavedState(Parcel in) {
	super(in);
	checked = (Boolean)in.readValue(null);
	}

	@Override
	public void writeToParcel(Parcel out, int flags) {
	super.writeToParcel(out, flags);
	out.writeValue(checked);
	}

	@Override
	public String toString() {
	return "CompoundButton.SavedState{"
	+ Integer.toHexString(System.identityHashCode(this))
	+ " checked=" + checked + "}";
	}

	public static final Parcelable.Creator<SavedState> CREATOR
	= new Parcelable.Creator<SavedState>() {
	public SavedState createFromParcel(Parcel in) {
	return new SavedState(in);
	}

	public SavedState[] newArray(int size) {
	return new SavedState[size];
	}
	};
	}

	@Override
	public Parcelable onSaveInstanceState() {
	// Force our ancestor class to save its state
	setFreezesText(true);
	Parcelable superState = super.onSaveInstanceState();

	SavedState ss = new SavedState(superState);

	ss.checked = isChecked();
	return ss;
	}

	@Override
	public void onRestoreInstanceState(Parcelable state) {
	SavedState ss = (SavedState) state;

	super.onRestoreInstanceState(ss.getSuperState());
	setChecked(ss.checked);
	requestLayout();
	}
	}