Android 按键式事件

package com.fish.helloworld;import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.util.Log;
import android.view.KeyEvent;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;public class MainActivity extends Activity { private ImageView m_ImageView;
private TextView m_TextView;
private float m_AlphaValue; @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_test_key); m_ImageView = (ImageView)findViewById(R.id.imageView1);
m_TextView = (TextView)findViewById(R.id.textView1);
m_AlphaValue = 0xFF; m_ImageView.setAlpha(m_AlphaValue);
m_TextView.setText("Alpha = " + m_AlphaValue * 100 / 0xff + "%");
} @Override
public boolean onKeyDown(int keyCode, KeyEvent msg){ Log.v("KeyCode","KeyCode = " + keyCode);
Log.v("msg","msg = " + msg); switch(keyCode){
case KeyEvent.KEYCODE_VOLUME_UP:
m_AlphaValue += 20;
break;
case KeyEvent.KEYCODE_VOLUME_DOWN:
m_AlphaValue -= 20;
break;
default:
break; } if(m_AlphaValue >= 0xFF) m_AlphaValue = 0xFF;
if(m_AlphaValue <= 0x00) m_AlphaValue = 0x0; m_ImageView.setAlpha(m_AlphaValue);
m_TextView.setText("Alpha = " + m_AlphaValue * 100 / 0xff + "%"); return super.onKeyDown(keyCode, msg);
}
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" > <TextView
android:id="@+id/textView1"
android:layout_width="110dp"
android:layout_height="wrap_content"
android:layout_weight="0.03"
android:text="TextView" /> <ImageView
android:id="@+id/imageView1"
android:layout_width="241dp"
android:layout_height="195dp"
android:layout_marginRight="37dp"
android:layout_marginTop="176dp"
android:layout_weight="0.06"
android:src="@drawable/ic_launcher" /></LinearLayout>

package com.fish.helloworld;import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.util.Log;
import android.view.KeyEvent;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;public class MainActivity extends Activity { private TextView m_TextView;
private TextView m_TextView2; @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.skeleton_activity); m_TextView = (TextView)findViewById(R.id.textView1);
m_TextView2 = (TextView)findViewById(R.id.textView2); } @Override
public boolean onTouchEvent(MotionEvent event){ int action = event.getAction();
float x = event.getX();
float y = event.getY(); m_TextView.setText("Action = " + action);
m_TextView2.setText(x + " + " + y); return true;
}}