【Android】タッチ操作で様々なアクションを行う

package com.lesson.touch;

import android.view.MotionEvent;

import com.lesson.touch.Waiter.OnWaitCompletedListener;

class TouchEventDispatcher{
	interface TouchEventDispatcherListener{
		void onTap(float x, float y);
		void onDoubleTap(float x, float y);
		void onMove(float initX, float initY, float x, float y);
		void onHold(float x, float y);
	}
	
	private static final int DOUBLE_TAP_WAIT_MILLI_SECOND = 500;
	private static final double MOVE_DISTANCE = 20;
	
	private TouchEventDispatcherListener listener;
	public void setTouchEventDispatcherListener(TouchEventDispatcherListener listener){
		this.listener = listener;
	}
	
	private boolean holdExecuted = false;
	private float initX;
	private float initY;
	private int actionUpCount = 0;
	
	private final Waiter waiter = new Waiter(DOUBLE_TAP_WAIT_MILLI_SECOND);
	
	// 初期化
	{
		waiter.setOnWaitCompletedListener(new OnWaitCompletedListener() {
			
			@Override
			public void onWaitCompleted() {

				if( 0 < actionUpCount ){
					// シングルタップ実行
					listener.onTap(initX, initY);
				}
				else
				{
					// ホールド実行
					listener.onHold(initX, initY);
					holdExecuted = true;
				}
			}
		});
	}
	   
	/**
	 * @param event
	 */
	public void onTouchEvent(MotionEvent event) {
		
		if(event.getAction()==MotionEvent.ACTION_DOWN){
    		
			holdExecuted = false;
			
			if(!waiter.isWaiting()){
				
				initX = event.getX();
				initY = event.getY();
				actionUpCount = 0;
				
				waiter.start();
			}
	    }
	    else if(event.getAction()==MotionEvent.ACTION_MOVE){
	    		
	    	if( !holdExecuted ){
	        	double distance = Math.sqrt(
	        			Math.pow(event.getX() - initX, 2) + Math.pow(event.getY() - initY, 2));
	        		
	        	if( waiter.isWaiting() && MOVE_DISTANCE < distance ){
	        		waiter.cancel();
	        	}
	        		
	        	if( !waiter.isWaiting() && listener != null){
	        		// ムーブイベント起動
	        		listener.onMove(initX, initY, event.getX(), event.getY());
	        	}
	    	}
	    }
	    else if(event.getAction()==MotionEvent.ACTION_UP){
	    		
	    	if( waiter.isWaiting() && 1 < ++actionUpCount ){
	    		waiter.cancel();
	    			
	    		if( listener != null){
	    			// ダブルタップ実行
	    			listener.onDoubleTap(event.getX(), event.getY());
	    		}
	    	}
	    }
	}
}

package com.lesson.touch;

import android.os.Handler;


class Waiter{
	public interface OnWaitCompletedListener{
		void onWaitCompleted();
	}
	
	private OnWaitCompletedListener listener;
	public void setOnWaitCompletedListener(OnWaitCompletedListener listener){
		this.listener = listener;
	}
	
	private final int waitMilliSeconds;
	private final Handler handler = new Handler();
	private final Runnable runnable = new Runnable() {
		
		@Override
		public void run() {
			waiting = false;
			if( listener != null ){
				listener.onWaitCompleted();
			}
		}
	};
	
	private boolean waiting = false;
	
	/**
	 * @param waitMilliSeconds
	 */
	public Waiter(int waitMilliSeconds){
		this.waitMilliSeconds = waitMilliSeconds;
	}
	
	/**
	 * Waitスタート
	 */
	public void start(){
		waiting = true;
		handler.postDelayed(runnable, waitMilliSeconds);
	}
	
	/**
	 * Waitキャンセル
	 */
	public void cancel(){
		if( waiting ){
			waiting = false;
			handler.removeCallbacks(runnable);
		}
	}
	
	/**
	 * Wait中かどうか
	 * @return
	 */
	public boolean isWaiting(){
		return waiting;
	}
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
	android:id="@+id/info"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text=""
    />
</LinearLayout>

package com.lesson.touch;

import android.app.Activity;
import android.os.Bundle;
import android.view.MotionEvent;
import android.widget.TextView;

public class MainActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        final TextView info = (TextView)findViewById(R.id.info);
        
        touchEventDispatcher.setTouchEventDispatcherListener(new TouchEventDispatcher.TouchEventDispatcherListener() {
			
			@Override
			public void onTap(float x, float y) {
				info.setText("onTap x:" + x + " y:" + y);
			}
			
			@Override
			public void onMove(float initX, float initY, float x, float y) {
				info.setText("onMove x:" + x + " y:" + y);
			}
			
			@Override
			public void onHold(float x, float y) {
				info.setText("onHold x:" + x + " y:" + y);
			}
			
			@Override
			public void onDoubleTap(float x, float y) {
				info.setText("onDoubleTap x:" + x + " y:" + y);
			}
		});
    }


    
    private final TouchEventDispatcher touchEventDispatcher = new TouchEventDispatcher();
    
    @Override
    public boolean onTouchEvent(MotionEvent event) {
    	
    	touchEventDispatcher.onTouchEvent(event);
    	return true;
    }
}