src/com/android/calculator2/CalculatorFormula.java - platform/packages/apps/ExactCalculator - Gitiles

 /*
  * Copyright (C) 2015 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 com.android.calculator2;

 import android.annotation.TargetApi;
 import android.content.ClipData;
 import android.content.ClipboardManager;
 import android.content.Context;
 import android.content.res.TypedArray;
 import android.graphics.Rect;
 import android.os.Build;
 import android.text.Layout;
 import android.text.TextPaint;
 import android.text.TextUtils;
 import android.util.AttributeSet;
 import android.util.Log;
 import android.util.TypedValue;
 import android.view.ActionMode;
 import android.view.ContextMenu;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
 import android.view.View;
 import android.widget.TextView;

 /**
  * TextView adapted for displaying the formula and allowing pasting.
  */
 public class CalculatorFormula extends AlignedTextView implements MenuItem.OnMenuItemClickListener,
         ClipboardManager.OnPrimaryClipChangedListener {

     public static final String TAG_ACTION_MODE = "ACTION_MODE";

     // Temporary paint for use in layout methods.
     private final TextPaint mTempPaint = new TextPaint();

     private final float mMaximumTextSize;
     private final float mMinimumTextSize;
     private final float mStepTextSize;

     private final ClipboardManager mClipboardManager;

     private int mWidthConstraint = -1;
     private ActionMode mActionMode;
     private ActionMode.Callback mPasteActionModeCallback;
     private ContextMenu mContextMenu;
     private OnTextSizeChangeListener mOnTextSizeChangeListener;
     private OnFormulaContextMenuClickListener mOnContextMenuClickListener;
     private Calculator.OnDisplayMemoryOperationsListener mOnDisplayMemoryOperationsListener;

     public CalculatorFormula(Context context) {
         this(context, null /* attrs */);
     }

     public CalculatorFormula(Context context, AttributeSet attrs) {
         this(context, attrs, 0 /* defStyleAttr */);
     }

     public CalculatorFormula(Context context, AttributeSet attrs, int defStyleAttr) {
         super(context, attrs, defStyleAttr);

         mClipboardManager = (ClipboardManager) context.getSystemService(Context.CLIPBOARD_SERVICE);

         final TypedArray a = context.obtainStyledAttributes(
                 attrs, R.styleable.CalculatorFormula, defStyleAttr, 0);
         mMaximumTextSize = a.getDimension(
                 R.styleable.CalculatorFormula_maxTextSize, getTextSize());
         mMinimumTextSize = a.getDimension(
                 R.styleable.CalculatorFormula_minTextSize, getTextSize());
         mStepTextSize = a.getDimension(R.styleable.CalculatorFormula_stepTextSize,
                 (mMaximumTextSize - mMinimumTextSize) / 3);
         a.recycle();

         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
             setupActionMode();
         } else {
             setupContextMenu();
         }
     }

     @Override
     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
         if (!isLaidOut()) {
             // Prevent shrinking/resizing with our variable textSize.
             setTextSizeInternal(TypedValue.COMPLEX_UNIT_PX, mMaximumTextSize,
                     false /* notifyListener */);
             setMinimumHeight(getLineHeight() + getCompoundPaddingBottom()
                     + getCompoundPaddingTop());
         }

         // Ensure we are at least as big as our parent.
         final int width = MeasureSpec.getSize(widthMeasureSpec);
         if (getMinimumWidth() != width) {
             setMinimumWidth(width);
         }

         // Re-calculate our textSize based on new width.
         mWidthConstraint = MeasureSpec.getSize(widthMeasureSpec)
                 - getPaddingLeft() - getPaddingRight();
         final float textSize = getVariableTextSize(getText());
         if (getTextSize() != textSize) {
             setTextSizeInternal(TypedValue.COMPLEX_UNIT_PX, textSize, false /* notifyListener */);
         }

         super.onMeasure(widthMeasureSpec, heightMeasureSpec);
     }

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

         mClipboardManager.addPrimaryClipChangedListener(this);
         onPrimaryClipChanged();
     }

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

         mClipboardManager.removePrimaryClipChangedListener(this);
     }

     @Override
     protected void onTextChanged(CharSequence text, int start, int lengthBefore, int lengthAfter) {
         super.onTextChanged(text, start, lengthBefore, lengthAfter);

         setTextSize(TypedValue.COMPLEX_UNIT_PX, getVariableTextSize(text.toString()));
     }

     private void setTextSizeInternal(int unit, float size, boolean notifyListener) {
         final float oldTextSize = getTextSize();
         super.setTextSize(unit, size);
         if (notifyListener && mOnTextSizeChangeListener != null && getTextSize() != oldTextSize) {
             mOnTextSizeChangeListener.onTextSizeChanged(this, oldTextSize);
         }
     }

     @Override
     public void setTextSize(int unit, float size) {
         setTextSizeInternal(unit, size, true);
     }

     public float getMinimumTextSize() {
         return mMinimumTextSize;
     }

     public float getMaximumTextSize() {
         return mMaximumTextSize;
     }

     public float getVariableTextSize(CharSequence text) {
         if (mWidthConstraint < 0 || mMaximumTextSize <= mMinimumTextSize) {
             // Not measured, bail early.
             return getTextSize();
         }

         // Capture current paint state.
         mTempPaint.set(getPaint());

         // Step through increasing text sizes until the text would no longer fit.
         float lastFitTextSize = mMinimumTextSize;
         while (lastFitTextSize < mMaximumTextSize) {
             mTempPaint.setTextSize(Math.min(lastFitTextSize + mStepTextSize, mMaximumTextSize));
             if (Layout.getDesiredWidth(text, mTempPaint) > mWidthConstraint) {
                 break;
             }
             lastFitTextSize = mTempPaint.getTextSize();
         }

         return lastFitTextSize;
     }

     /**
      * Functionally equivalent to setText(), but explicitly announce changes.
      * If the new text is an extension of the old one, announce the addition.
      * Otherwise, e.g. after deletion, announce the entire new text.
      */
     public void changeTextTo(CharSequence newText) {
         final CharSequence oldText = getText();
         final char separator = KeyMaps.translateResult(",").charAt(0);
         final CharSequence added = StringUtils.getExtensionIgnoring(newText, oldText, separator);
         if (added != null) {
             if (added.length() == 1) {
                 // The algorithm for pronouncing a single character doesn't seem
                 // to respect our hints.  Don't give it the choice.
                 final char c = added.charAt(0);
                 final int id = KeyMaps.keyForChar(c);
                 final String descr = KeyMaps.toDescriptiveString(getContext(), id);
                 if (descr != null) {
                     announceForAccessibility(descr);
                 } else {
                     announceForAccessibility(String.valueOf(c));
                 }
             } else if (added.length() != 0) {
                 announceForAccessibility(added);
             }
         } else {
             announceForAccessibility(newText);
         }
         setText(newText, BufferType.SPANNABLE);
     }

     public boolean stopActionModeOrContextMenu() {
         if (mActionMode != null) {
             mActionMode.finish();
             return true;
         }
         if (mContextMenu != null) {
             mContextMenu.close();
             return true;
         }
         return false;
     }

     public void setOnTextSizeChangeListener(OnTextSizeChangeListener listener) {
         mOnTextSizeChangeListener = listener;
     }

     public void setOnContextMenuClickListener(OnFormulaContextMenuClickListener listener) {
         mOnContextMenuClickListener = listener;
     }

     public void setOnDisplayMemoryOperationsListener(
             Calculator.OnDisplayMemoryOperationsListener listener) {
         mOnDisplayMemoryOperationsListener = listener;
     }

     /**
      * Use ActionMode for paste support on M and higher.
      */
     @TargetApi(Build.VERSION_CODES.M)
     private void setupActionMode() {
         mPasteActionModeCallback = new ActionMode.Callback2() {

             @Override
             public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
                 if (onMenuItemClick(item)) {
                     mode.finish();
                     return true;
                 } else {
                     return false;
                 }
             }

             @Override
             public boolean onCreateActionMode(ActionMode mode, Menu menu) {
                 mode.setTag(TAG_ACTION_MODE);
                 final MenuInflater inflater = mode.getMenuInflater();
                 return createContextMenu(inflater, menu);
             }

             @Override
             public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
                 return false;
             }

             @Override
             public void onDestroyActionMode(ActionMode mode) {
                 mActionMode = null;
             }

             @Override
             public void onGetContentRect(ActionMode mode, View view, Rect outRect) {
                 super.onGetContentRect(mode, view, outRect);
                 outRect.top += getTotalPaddingTop();
                 outRect.right -= getTotalPaddingRight();
                 outRect.bottom -= getTotalPaddingBottom();
                 // Encourage menu positioning over the rightmost 10% of the screen.
                 outRect.left = (int) (outRect.right * 0.9f);
             }
         };
         setOnLongClickListener(new View.OnLongClickListener() {
             @Override
             public boolean onLongClick(View v) {
                 mActionMode = startActionMode(mPasteActionModeCallback, ActionMode.TYPE_FLOATING);
                 return true;
             }
         });
     }

     /**
      * Use ContextMenu for paste support on L and lower.
      */
     private void setupContextMenu() {
         setOnCreateContextMenuListener(new OnCreateContextMenuListener() {
             @Override
             public void onCreateContextMenu(ContextMenu contextMenu, View view,
                     ContextMenu.ContextMenuInfo contextMenuInfo) {
                 final MenuInflater inflater = new MenuInflater(getContext());
                 createContextMenu(inflater, contextMenu);
                 mContextMenu = contextMenu;
                 for (int i = 0; i < contextMenu.size(); i++) {
                     contextMenu.getItem(i).setOnMenuItemClickListener(CalculatorFormula.this);
                 }
             }
         });
         setOnLongClickListener(new View.OnLongClickListener() {
             @Override
             public boolean onLongClick(View v) {
                 return showContextMenu();
             }
         });
     }

     private boolean createContextMenu(MenuInflater inflater, Menu menu) {
         final boolean isPasteEnabled = isPasteEnabled();
         final boolean isMemoryEnabled = isMemoryEnabled();
         if (!isPasteEnabled && !isMemoryEnabled) {
             return false;
         }

         bringPointIntoView(length());
         inflater.inflate(R.menu.menu_formula, menu);
         final MenuItem pasteItem = menu.findItem(R.id.menu_paste);
         final MenuItem memoryRecallItem = menu.findItem(R.id.memory_recall);
         pasteItem.setEnabled(isPasteEnabled);
         memoryRecallItem.setEnabled(isMemoryEnabled);
         return true;
     }

     private void paste() {
         final ClipData primaryClip = mClipboardManager.getPrimaryClip();
         if (primaryClip != null && mOnContextMenuClickListener != null) {
             mOnContextMenuClickListener.onPaste(primaryClip);
         }
     }

     @Override
     public boolean onMenuItemClick(MenuItem item) {
         switch (item.getItemId()) {
             case R.id.memory_recall:
                 mOnContextMenuClickListener.onMemoryRecall();
                 return true;
             case R.id.menu_paste:
                 paste();
                 return true;
             default:
                 return false;
         }
     }

     @Override
     public void onPrimaryClipChanged() {
         setLongClickable(isPasteEnabled() || isMemoryEnabled());
     }

     public void onMemoryStateChanged() {
         setLongClickable(isPasteEnabled() || isMemoryEnabled());
     }

     private boolean isMemoryEnabled() {
         return mOnDisplayMemoryOperationsListener != null
                 && mOnDisplayMemoryOperationsListener.shouldDisplayMemory();
     }

     private boolean isPasteEnabled() {
         final ClipData clip = mClipboardManager.getPrimaryClip();
         if (clip == null || clip.getItemCount() == 0) {
             return false;
         }
         CharSequence clipText = null;
         try {
             clipText = clip.getItemAt(0).coerceToText(getContext());
         } catch (Exception e) {
             Log.i("Calculator", "Error reading clipboard:", e);
         }
         return !TextUtils.isEmpty(clipText);
     }

     public interface OnTextSizeChangeListener {
         void onTextSizeChanged(TextView textView, float oldSize);
     }

     public interface OnFormulaContextMenuClickListener {
         boolean onPaste(ClipData clip);
         void onMemoryRecall();
     }
 }
	/*
	* Copyright (C) 2015 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 com.android.calculator2;

	import android.annotation.TargetApi;
	import android.content.ClipData;
	import android.content.ClipboardManager;
	import android.content.Context;
	import android.content.res.TypedArray;
	import android.graphics.Rect;
	import android.os.Build;
	import android.text.Layout;
	import android.text.TextPaint;
	import android.text.TextUtils;
	import android.util.AttributeSet;
	import android.util.Log;
	import android.util.TypedValue;
	import android.view.ActionMode;
	import android.view.ContextMenu;
	import android.view.Menu;
	import android.view.MenuInflater;
	import android.view.MenuItem;
	import android.view.View;
	import android.widget.TextView;

	/**
	* TextView adapted for displaying the formula and allowing pasting.
	*/
	public class CalculatorFormula extends AlignedTextView implements MenuItem.OnMenuItemClickListener,
	ClipboardManager.OnPrimaryClipChangedListener {

	public static final String TAG_ACTION_MODE = "ACTION_MODE";

	// Temporary paint for use in layout methods.
	private final TextPaint mTempPaint = new TextPaint();

	private final float mMaximumTextSize;
	private final float mMinimumTextSize;
	private final float mStepTextSize;

	private final ClipboardManager mClipboardManager;

	private int mWidthConstraint = -1;
	private ActionMode mActionMode;
	private ActionMode.Callback mPasteActionModeCallback;
	private ContextMenu mContextMenu;
	private OnTextSizeChangeListener mOnTextSizeChangeListener;
	private OnFormulaContextMenuClickListener mOnContextMenuClickListener;
	private Calculator.OnDisplayMemoryOperationsListener mOnDisplayMemoryOperationsListener;

	public CalculatorFormula(Context context) {
	this(context, null /* attrs */);
	}

	public CalculatorFormula(Context context, AttributeSet attrs) {
	this(context, attrs, 0 /* defStyleAttr */);
	}

	public CalculatorFormula(Context context, AttributeSet attrs, int defStyleAttr) {
	super(context, attrs, defStyleAttr);

	mClipboardManager = (ClipboardManager) context.getSystemService(Context.CLIPBOARD_SERVICE);

	final TypedArray a = context.obtainStyledAttributes(
	attrs, R.styleable.CalculatorFormula, defStyleAttr, 0);
	mMaximumTextSize = a.getDimension(
	R.styleable.CalculatorFormula_maxTextSize, getTextSize());
	mMinimumTextSize = a.getDimension(
	R.styleable.CalculatorFormula_minTextSize, getTextSize());
	mStepTextSize = a.getDimension(R.styleable.CalculatorFormula_stepTextSize,
	(mMaximumTextSize - mMinimumTextSize) / 3);
	a.recycle();

	if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
	setupActionMode();
	} else {
	setupContextMenu();
	}
	}

	@Override
	protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
	if (!isLaidOut()) {
	// Prevent shrinking/resizing with our variable textSize.
	setTextSizeInternal(TypedValue.COMPLEX_UNIT_PX, mMaximumTextSize,
	false /* notifyListener */);
	setMinimumHeight(getLineHeight() + getCompoundPaddingBottom()
	+ getCompoundPaddingTop());
	}

	// Ensure we are at least as big as our parent.
	final int width = MeasureSpec.getSize(widthMeasureSpec);
	if (getMinimumWidth() != width) {
	setMinimumWidth(width);
	}

	// Re-calculate our textSize based on new width.
	mWidthConstraint = MeasureSpec.getSize(widthMeasureSpec)
	- getPaddingLeft() - getPaddingRight();
	final float textSize = getVariableTextSize(getText());
	if (getTextSize() != textSize) {
	setTextSizeInternal(TypedValue.COMPLEX_UNIT_PX, textSize, false /* notifyListener */);
	}

	super.onMeasure(widthMeasureSpec, heightMeasureSpec);
	}

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

	mClipboardManager.addPrimaryClipChangedListener(this);
	onPrimaryClipChanged();
	}

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

	mClipboardManager.removePrimaryClipChangedListener(this);
	}

	@Override
	protected void onTextChanged(CharSequence text, int start, int lengthBefore, int lengthAfter) {
	super.onTextChanged(text, start, lengthBefore, lengthAfter);

	setTextSize(TypedValue.COMPLEX_UNIT_PX, getVariableTextSize(text.toString()));
	}

	private void setTextSizeInternal(int unit, float size, boolean notifyListener) {
	final float oldTextSize = getTextSize();
	super.setTextSize(unit, size);
	if (notifyListener && mOnTextSizeChangeListener != null && getTextSize() != oldTextSize) {
	mOnTextSizeChangeListener.onTextSizeChanged(this, oldTextSize);
	}
	}

	@Override
	public void setTextSize(int unit, float size) {
	setTextSizeInternal(unit, size, true);
	}

	public float getMinimumTextSize() {
	return mMinimumTextSize;
	}

	public float getMaximumTextSize() {
	return mMaximumTextSize;
	}

	public float getVariableTextSize(CharSequence text) {
	if (mWidthConstraint < 0 \|\| mMaximumTextSize <= mMinimumTextSize) {
	// Not measured, bail early.
	return getTextSize();
	}

	// Capture current paint state.
	mTempPaint.set(getPaint());

	// Step through increasing text sizes until the text would no longer fit.
	float lastFitTextSize = mMinimumTextSize;
	while (lastFitTextSize < mMaximumTextSize) {
	mTempPaint.setTextSize(Math.min(lastFitTextSize + mStepTextSize, mMaximumTextSize));
	if (Layout.getDesiredWidth(text, mTempPaint) > mWidthConstraint) {
	break;
	}
	lastFitTextSize = mTempPaint.getTextSize();
	}

	return lastFitTextSize;
	}

	/**
	* Functionally equivalent to setText(), but explicitly announce changes.
	* If the new text is an extension of the old one, announce the addition.
	* Otherwise, e.g. after deletion, announce the entire new text.
	*/
	public void changeTextTo(CharSequence newText) {
	final CharSequence oldText = getText();
	final char separator = KeyMaps.translateResult(",").charAt(0);
	final CharSequence added = StringUtils.getExtensionIgnoring(newText, oldText, separator);
	if (added != null) {
	if (added.length() == 1) {
	// The algorithm for pronouncing a single character doesn't seem
	// to respect our hints. Don't give it the choice.
	final char c = added.charAt(0);
	final int id = KeyMaps.keyForChar(c);
	final String descr = KeyMaps.toDescriptiveString(getContext(), id);
	if (descr != null) {
	announceForAccessibility(descr);
	} else {
	announceForAccessibility(String.valueOf(c));
	}
	} else if (added.length() != 0) {
	announceForAccessibility(added);
	}
	} else {
	announceForAccessibility(newText);
	}
	setText(newText, BufferType.SPANNABLE);
	}

	public boolean stopActionModeOrContextMenu() {
	if (mActionMode != null) {
	mActionMode.finish();
	return true;
	}
	if (mContextMenu != null) {
	mContextMenu.close();
	return true;
	}
	return false;
	}

	public void setOnTextSizeChangeListener(OnTextSizeChangeListener listener) {
	mOnTextSizeChangeListener = listener;
	}

	public void setOnContextMenuClickListener(OnFormulaContextMenuClickListener listener) {
	mOnContextMenuClickListener = listener;
	}

	public void setOnDisplayMemoryOperationsListener(
	Calculator.OnDisplayMemoryOperationsListener listener) {
	mOnDisplayMemoryOperationsListener = listener;
	}

	/**
	* Use ActionMode for paste support on M and higher.
	*/
	@TargetApi(Build.VERSION_CODES.M)
	private void setupActionMode() {
	mPasteActionModeCallback = new ActionMode.Callback2() {

	@Override
	public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
	if (onMenuItemClick(item)) {
	mode.finish();
	return true;
	} else {
	return false;
	}
	}

	@Override
	public boolean onCreateActionMode(ActionMode mode, Menu menu) {
	mode.setTag(TAG_ACTION_MODE);
	final MenuInflater inflater = mode.getMenuInflater();
	return createContextMenu(inflater, menu);
	}

	@Override
	public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
	return false;
	}

	@Override
	public void onDestroyActionMode(ActionMode mode) {
	mActionMode = null;
	}

	@Override
	public void onGetContentRect(ActionMode mode, View view, Rect outRect) {
	super.onGetContentRect(mode, view, outRect);
	outRect.top += getTotalPaddingTop();
	outRect.right -= getTotalPaddingRight();
	outRect.bottom -= getTotalPaddingBottom();
	// Encourage menu positioning over the rightmost 10% of the screen.
	outRect.left = (int) (outRect.right * 0.9f);
	}
	};
	setOnLongClickListener(new View.OnLongClickListener() {
	@Override
	public boolean onLongClick(View v) {
	mActionMode = startActionMode(mPasteActionModeCallback, ActionMode.TYPE_FLOATING);
	return true;
	}
	});
	}

	/**
	* Use ContextMenu for paste support on L and lower.
	*/
	private void setupContextMenu() {
	setOnCreateContextMenuListener(new OnCreateContextMenuListener() {
	@Override
	public void onCreateContextMenu(ContextMenu contextMenu, View view,
	ContextMenu.ContextMenuInfo contextMenuInfo) {
	final MenuInflater inflater = new MenuInflater(getContext());
	createContextMenu(inflater, contextMenu);
	mContextMenu = contextMenu;
	for (int i = 0; i < contextMenu.size(); i++) {
	contextMenu.getItem(i).setOnMenuItemClickListener(CalculatorFormula.this);
	}
	}
	});
	setOnLongClickListener(new View.OnLongClickListener() {
	@Override
	public boolean onLongClick(View v) {
	return showContextMenu();
	}
	});
	}

	private boolean createContextMenu(MenuInflater inflater, Menu menu) {
	final boolean isPasteEnabled = isPasteEnabled();
	final boolean isMemoryEnabled = isMemoryEnabled();
	if (!isPasteEnabled && !isMemoryEnabled) {
	return false;
	}

	bringPointIntoView(length());
	inflater.inflate(R.menu.menu_formula, menu);
	final MenuItem pasteItem = menu.findItem(R.id.menu_paste);
	final MenuItem memoryRecallItem = menu.findItem(R.id.memory_recall);
	pasteItem.setEnabled(isPasteEnabled);
	memoryRecallItem.setEnabled(isMemoryEnabled);
	return true;
	}

	private void paste() {
	final ClipData primaryClip = mClipboardManager.getPrimaryClip();
	if (primaryClip != null && mOnContextMenuClickListener != null) {
	mOnContextMenuClickListener.onPaste(primaryClip);
	}
	}

	@Override
	public boolean onMenuItemClick(MenuItem item) {
	switch (item.getItemId()) {
	case R.id.memory_recall:
	mOnContextMenuClickListener.onMemoryRecall();
	return true;
	case R.id.menu_paste:
	paste();
	return true;
	default:
	return false;
	}
	}

	@Override
	public void onPrimaryClipChanged() {
	setLongClickable(isPasteEnabled() \|\| isMemoryEnabled());
	}

	public void onMemoryStateChanged() {
	setLongClickable(isPasteEnabled() \|\| isMemoryEnabled());
	}

	private boolean isMemoryEnabled() {
	return mOnDisplayMemoryOperationsListener != null
	&& mOnDisplayMemoryOperationsListener.shouldDisplayMemory();
	}

	private boolean isPasteEnabled() {
	final ClipData clip = mClipboardManager.getPrimaryClip();
	if (clip == null \|\| clip.getItemCount() == 0) {
	return false;
	}
	CharSequence clipText = null;
	try {
	clipText = clip.getItemAt(0).coerceToText(getContext());
	} catch (Exception e) {
	Log.i("Calculator", "Error reading clipboard:", e);
	}
	return !TextUtils.isEmpty(clipText);
	}

	public interface OnTextSizeChangeListener {
	void onTextSizeChanged(TextView textView, float oldSize);
	}

	public interface OnFormulaContextMenuClickListener {
	boolean onPaste(ClipData clip);
	void onMemoryRecall();
	}
	}