Java tutorial
/* 50AH-code ========= 50 Android Hacks (http://manning.com/sessa/) book source code Copyright (c) 2012 Manning Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package roboguice.calculator.view; import com.google.inject.Inject; import roboguice.RoboGuice; import roboguice.activity.event.OnResumeEvent; import roboguice.calculator.util.RpnStack; import android.content.Context; import android.util.AttributeSet; import android.widget.TextView; import roboguice.event.Observes; import java.util.Stack; /** * A simple TextView that knows how to read an RpnStack * and display it. * * @see {@link #refresh()} */ public class TickerTapeView extends TextView { @Inject RpnStack stack; public TickerTapeView(Context context, AttributeSet attrs) { super(context, attrs); RoboGuice.injectMembers(context, this); } public void refresh() { Stack<String> lines = new Stack<String>(); String digitAccumulator = stack.getDigitAccumulator(); // Include the current number that the user is typing in the display if (digitAccumulator.length() > 0) lines.push(digitAccumulator); // Include up to 3 lines of stack for (int i = 0; lines.size() < 3 && i < stack.size(); ++i) lines.push(stack.get(stack.size() - i - 1).toString()); // Convert to text String text = ""; for (String line : lines) text = line + "\n" + text + "\n"; setText(text.trim()); } protected void onResume(@Observes OnResumeEvent e) { refresh(); } }