آموزش حرکات در اندروید

GestureDetector myG;
myG = new GestureDetector(this,new Gesture());
   
   class Gesture extends GestureDetector.SimpleOnGestureListener{
      public boolean onSingleTapUp(MotionEvent ev) {
   }
   
   public void onLongPress(MotionEvent ev) {
   }
   
   public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,
   float distanceY) {
   }
   
   public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
   float velocityY) {
   }
}
}

ScaleGestureDetector SGD;
SGD = new ScaleGestureDetector(this,new ScaleListener());
اولین پارامتر کانتکست و دمین پارامتر شنونده ی رویداد (event listener) می باشد. ما باید رویداد شنونده را تعریف کرده و از عملکرد OnTouchEvent برای به کار انداختن آن استفاده کنیم. ترکیب آن را در زیر می بینید

public boolean onTouchEvent(MotionEvent ev) {
   SGD.onTouchEvent(ev);
   return true;
}

private class ScaleListener extends ScaleGestureDetector.SimpleOnScaleGestureListener {
   @Override
   public boolean onScale(ScaleGestureDetector detector) {
      float scale = detector.getScaleFactor();
      return true;
   }
}

package com.example.sairamkrishna.myapplication;

import android.app.Activity;
import android.content.Intent;
import android.content.IntentFilter;

import android.graphics.Bitmap;
import android.graphics.Matrix;

import android.os.BatteryManager;
import android.os.Bundle;

import android.view.Menu;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;

import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;

import java.util.ArrayList;
import java.util.Set;

public class MainActivity extends Activity {
   private ImageView iv;
   private Matrix matrix = new Matrix();
   private float scale = 1f;
   private ScaleGestureDetector SGD;
   
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      
      iv=(ImageView)findViewById(R.id.imageView);
      SGD = new ScaleGestureDetector(this,new ScaleListener());
   }
   
   public boolean onTouchEvent(MotionEvent ev) {
      SGD.onTouchEvent(ev);
      return true;
   }
   
   private class ScaleListener extends ScaleGestureDetector.
   
   SimpleOnScaleGestureListener {
      @Override
      public boolean onScale(ScaleGestureDetector detector) {
         scale *= detector.getScaleFactor();
         scale = Math.max(0.1f, Math.min(scale, 5.0f));
         
         matrix.setScale(scale, scale);
         iv.setImageMatrix(matrix);
         return true;
      }
   }
   
   @Override
   public boolean onCreateOptionsMenu(Menu menu) {
      // Inflate the menu; this adds items to the action bar if it is present.
      getMenuInflater().inflate(R.menu.menu_main, menu);
      return true;
   }
   
   @Override
   public boolean onOptionsItemSelected(MenuItem item) {
      // Handle action bar item clicks here. The action bar will
      // automatically handle clicks on the Home/Up button, so long
      // as you specify a parent activity in AndroidManifest.xml.
      
      int id = item.getItemId();
      
      //noinspection SimplifiableIfStatement
      if (id == R.id.action_settings) {
         return true;
      }
      return super.onOptionsItemSelected(item);
   }
}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
   android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin"
   android:paddingRight="@dimen/activity_horizontal_margin"
   android:paddingTop="@dimen/activity_vertical_margin"
   android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity" >
   
   <TextView android:text="Gestures  Example" android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:id="@+id/textview"
      android:textSize="35dp"
      android:layout_alignParentTop="true"
      android:layout_centerHorizontal="true" />
      
   <TextView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:text="Tutorials point"
      android:id="@+id/textView"
      android:layout_below="@+id/textview"
      android:layout_centerHorizontal="true"
      android:textColor="#ff7aff24"
      android:textSize="35dp" />
      
   <ImageView
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:id="@+id/imageView"
      android:src="@drawable/abc"
      android:scaleType="matrix"
      android:layout_below="@+id/textView"
      android:layout_alignParentLeft="true"
      android:layout_alignParentStart="true"
      android:layout_alignParentBottom="true"
      android:layout_alignParentRight="true"
      android:layout_alignParentEnd="true" />
      
</RelativeLayout>

<resources>

   <string name="app_name>My Application</string>

   <string name="hello_world">Hello world!</string>

   <string name="action_settings">Settings</string>

</resources>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
   package="com.example.gestures"
   android:versionCode="1"
   android:versionName="1.0" >

   <application
      android:allowBackup="true"
      android:icon="@drawable/ic_launcher"
      android:label="@string/app_name"
      android:theme="@style/AppTheme" >
      
      <activity
         android:name="com.example.sairamkrishna.myapplicationMainActivity"
         android:label="@string/app_name" >
         
         <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
         </intent-filter>
         
      </activity>
   
   </application>
</manifest>