19_Android中图片处理原理篇，关于人脸识别站点，图片载入到内存，图片缩放，图片翻转倒置，网上撕衣服游戏案例编写

package com.itheima.play;

import android.app.Activity;

import android.graphics.Bitmap;

import android.graphics.BitmapFactory;

import android.graphics.Canvas;

import android.graphics.Color;

import android.graphics.Matrix;

import android.graphics.Paint;

import android.media.MediaPlayer;

import android.os.Bundle;

import android.view.MotionEvent;

import android.view.View;

import android.view.View.OnTouchListener;

import android.widget.ImageView;

public class MainActivity extends Activity {

private ImageView iv;

// 能够改动的位图

private Bitmap alertBitmap;

private Canvas canvas;

@Override

protected void onCreate(Bundle savedInstanceState) {

super .onCreate(savedInstanceState);

setContentView(R.layout. activity_main );

iv = (ImageView) findViewById(R.id. iv );

Bitmap bitmap = BitmapFactory. decodeResource (getResources(),

R.drawable. pre );

// 创建一个空白的原图的拷贝

alertBitmap = Bitmap. createBitmap (bitmap.getWidth(),

bitmap.getHeight(), bitmap.getConfig());

canvas = new Canvas(alertBitmap);

Paint paint = new Paint();

paint.setColor(Color. BLACK );

canvas.drawBitmap(bitmap, new Matrix(), paint);

iv.setImageBitmap(alertBitmap);

iv.setOnTouchListener( new OnTouchListener() {

@Override

public boolean onTouch(View v, MotionEvent event) {

switch (event.getAction()) {

case MotionEvent. ACTION_DOWN :// 手指按下屏幕

System. out .println("action down");

break ;

case MotionEvent. ACTION_MOVE :// 手指在屏幕上移动

int x = ( int ) event.getX();

int y = ( int ) event.getY();

System. out .println("设置("+x+","+y+")透明颜色");

for ( int i=-4;i<5;i++){

for ( int j=-4;j<5;j++){

try {

alertBitmap.setPixel(x+i, y+j, Color. TRANSPARENT );

} catch (Exception e) {

e.printStackTrace();

}

}

}

iv.setImageBitmap(alertBitmap);

break ;

case MotionEvent. ACTION_UP :// 手指离开屏幕

MediaPlayer. create (getApplicationContext(), R.raw. higirl ).start();

break ;

}

return true ;//能够反复循环的处理事件

}

});

}

}

<?xml version= "1.0" encoding= "utf-8" ?

>

<manifest xmlns:android= "http://schemas.android.com/apk/res/android"

package= "com.itheima.play"

android:versionCode= "1"

android:versionName= "1.0" >

<uses-sdk

android:minSdkVersion= "8"

android:targetSdkVersion= "19" />

<application

android:allowBackup= "true"

android:icon= "@drawable/ic_launcher"

android:label= "@string/app_name"

android:theme= "@style/AppTheme" >

<activity

android:name= "com.itheima.play.MainActivity"

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>