The principle of the changing clothes game: There were originally 2 pictures, one original picture, and one after the clothes were changed. Put the two pictures together, the original picture is placed on top, the pixels of the top picture are set to transparent when sliding, and the pixels of the bottom picture are displayed.
Layout file
activity_main.xml
<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:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/xiatu" />
<ImageView
android:id="@+id/iv"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/shangtu" />
</RelativeLayout>
MainActivity.java
package com.ldw.siyifu;
import android.R.color;
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.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.ImageView;
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//获取到原图片
Bitmap bitSrc = BitmapFactory.decodeResource(getResources(), R.drawable.awaiyi);
//创建外衣副本
final Bitmap bitCopy = Bitmap.createBitmap(bitSrc.getWidth(), bitSrc.getHeight(), bitSrc.getConfig());
Paint paint = new Paint();
Canvas canvas = new Canvas(bitCopy);
canvas.drawBitmap(bitSrc, new Matrix(), paint);
final ImageView iv = (ImageView) findViewById(R.id.iv);
iv.setImageBitmap(bitCopy);
iv.setOnTouchListener(new OnTouchListener(){
@Override
public boolean onTouch(View v, MotionEvent event) {
int action = event.getAction();
switch(action){
//触摸屏幕
case MotionEvent.ACTION_DOWN:
break;
//屏幕上移动
case MotionEvent.ACTION_MOVE:
int x = (int) event.getX();
int y = (int) event.getY();
//限制编辑的区域，在图片的区域内才允许编辑
if(x <= bitCopy.getWidth() && y<= bitCopy.getHeight()){
//隐藏不止一个像素点，把周围的像素点都隐藏
for(int i = -5; i <= 5; i++){
for(int j = -5; j <= 5; j++){
//涂抹的像素点是一个圆形
if( i*i + j*j <= 25){
//防止越界,上下左右设置边界
if( x + i < bitCopy.getWidth() && y + j < bitCopy.getHeight() && x + i > 0 && y + j > 0){
//用户滑动过的坐标设置成透明
bitCopy.setPixel(x + i , y + j, Color.TRANSPARENT);
iv.setImageBitmap(bitCopy);
}
}
}
}
}
break;
//离开屏幕
case MotionEvent.ACTION_UP:
break;
}
//true:告诉系统，这个事件由自己处理，
//false:告诉系统，事件由自己处理，系统会把触摸事件发送到iamgeView的父节点
return true;
}
});
}
}