Android编程实现在Bitmap上涂鸦效果
本文实例讲述了Android编程实现在Bitmap上涂鸦效果。分享给大家供大家参考，具体如下：
布局文件：
<?xmlversion="1.0"encoding="utf-8"?> <LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical"> <LinearLayout android:id="@+id/handwriteview" android:layout_width="wrap_content" android:layout_height="wrap_content"/> <LinearLayout android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="horizontal" android:gravity="center_horizontal"> <Button android:id="@+id/clear" android:layout_width="200dp" android:layout_height="wrap_content" android:text="清屏"/> </LinearLayout> </LinearLayout>
重写的View文件：
publicclassHandWriteextendsView
{
privatePaintpaint=null;
privateBitmaporiginalBitmap=null;
privateBitmapnew1Bitmap=null;
privateBitmapnew2Bitmap=null;
privatefloatclickX=0,clickY=0;
privatefloatstartX=0,startY=0;
privatebooleanisMove=true;
privatebooleanisClear=false;
privateintcolor=Color.GREEN;
privatefloatstrokeWidth=2.0f;
publicHandWrite(Contextcontext,Bitmapb)
{
super(context);
originalBitmap=Bitmap.createBitmap(b).copy(Bitmap.Config.ARGB_8888,true);
new1Bitmap=Bitmap.createBitmap(originalBitmap);
}
publicvoidclear(){
isClear=true;
new2Bitmap=Bitmap.createBitmap(originalBitmap);
invalidate();
}
publicvoidsetstyle(floatstrokeWidth){
this.strokeWidth=strokeWidth;
}
@Override
protectedvoidonDraw(Canvascanvas)
{
super.onDraw(canvas);
canvas.drawBitmap(HandWriting(new1Bitmap),0,0,null);
}
publicBitmapHandWriting(BitmaporiginalBitmap)
{
Canvascanvas=null;
if(isClear){
canvas=newCanvas(new2Bitmap);
}
else{
canvas=newCanvas(originalBitmap);
}
paint=newPaint();
paint.setStyle(Style.STROKE);
paint.setAntiAlias(true);
paint.setColor(color);
paint.setStrokeWidth(strokeWidth);
if(isMove){
canvas.drawLine(startX,startY,clickX,clickY,paint);
}
startX=clickX;
startY=clickY;
if(isClear){
returnnew2Bitmap;
}
returnoriginalBitmap;
}
@Override
publicbooleanonTouchEvent(MotionEventevent)
{
clickX=event.getX();
clickY=event.getY();
if(event.getAction()==MotionEvent.ACTION_DOWN){
isMove=false;
invalidate();
returntrue;
}
elseif(event.getAction()==MotionEvent.ACTION_MOVE){
isMove=true;
invalidate();
returntrue;
}
returnsuper.onTouchEvent(event);
}
}
Activity文件：
publicclassHandWritingActivityextendsActivity
{
/**Calledwhentheactivityisfirstcreated.*/
privateLinearLayouthandWrite=null;
privateButtonclear=null;
intrequestWidth=116;
intrequestHeight=173;
intinSampleSize;
@Override
publicvoidonCreate(BundlesavedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_hand_writing);
handWrite=(LinearLayout)findViewById(R.id.handwriteview);
clear=(Button)findViewById(R.id.clear);
clear.setOnClickListener(newclearListener());
}
privateclassclearListenerimplementsOnClickListener{
publicvoidonClick(Viewv)
{
//handWrite.clear();
BitmapFactory.Optionsopts=newOptions();
opts.inJustDecodeBounds=true;//让bimapfactory假的解析这个位图,只获取位图的边框信息
BitmapFactory.decodeResource(getResources(),R.drawable.cool,opts);
if(opts.outHeight>requestHeight||opts.outWidth>requestWidth){
if(opts.outWidth>opts.outHeight){
inSampleSize=Math.round((float)opts.outHeight
/(float)requestHeight);
}else{
inSampleSize=Math.round((float)opts.outWidth
/(float)requestWidth);
}
}
System.out.println("宽度："+opts.outWidth);
System.out.println("高度："+opts.outHeight);
opts.inSampleSize=inSampleSize;
System.out.println(inSampleSize);
opts.inJustDecodeBounds=false;//由于已经得到了缩放比例,让位图工厂真正的解析这个位图
//由于前面我们已经解析了这个输入流,需要重新初始化这个输入流
Bitmapb=BitmapFactory.decodeResource(getResources(),R.drawable.cool,opts);
HandWritehw=newHandWrite(HandWritingActivity.this,b);
System.out.println(b.getWidth());
handWrite.addView(hw);
}
}
}
整合的一个涂鸦工具类：
/**
*使用方法：
*1.创建TuYaView类实例
*2.调用drawTuya方法
*3.参数1：context
*4.参数2：图像的byte[]字节数组
*5.ImageView实例
*6.画笔定义
***/
importcom.ziipin.lhdc.utils.ToastUtil;
importandroid.content.Context;
importandroid.graphics.Bitmap;
importandroid.graphics.BitmapFactory;
importandroid.graphics.Canvas;
importandroid.graphics.Matrix;
importandroid.graphics.Paint;
importandroid.graphics.BitmapFactory.Options;
importandroid.view.MotionEvent;
importandroid.view.View;
importandroid.view.View.OnTouchListener;
importandroid.widget.ImageView;
publicclassTuYaView{
//原始图片
privateBitmapmOrignBitmap;
privateBitmapmEditBitmap;
privateintinSampleSize;
privateintrequestWidth=500;
privateintrequestHeight=700;
/**编辑图片的画布*/
privateCanvasmCanvas;
privateImageViewimage;
privatePaintmPaint;
publicBitmapdrawTuya(Contextcontext,byte[]_data,ImageViewimage,
PaintmPaint){
this.image=image;
this.mPaint=mPaint;
mOrignBitmap=BitmapFactory.decodeByteArray(_data,0,_data.length);
returnshowEditBitmap(context,_data,image);
}
/**
*显示编辑的图片
*/
privateBitmapshowEditBitmap(Contextcontext,byte[]_data,ImageViewimage){
mOrignBitmap=getScaleBitmap(_data,image);
if(mOrignBitmap==null){
ToastUtil.show(context,"编辑出错");
}
mEditBitmap=mOrignBitmap.copy(mOrignBitmap.getConfig(),true);
mCanvas=newCanvas(mEditBitmap);
mCanvas.drawBitmap(mOrignBitmap,newMatrix(),newPaint());
image.setImageBitmap(mEditBitmap);
image.setOnTouchListener(mTouchListener);
returnmEditBitmap;
}
/**
*获取结果缩放放后的图片
*
*@return
*/
privateBitmapgetScaleBitmap(byte[]_data,ImageViewimage){
BitmapFactory.Optionsopts=newOptions();
opts.inJustDecodeBounds=true;//让bimapfactory假的解析这个位图,只获取位图的边框信息
BitmapFactory.decodeByteArray(_data,0,_data.length,opts);
if(opts.outHeight>requestHeight||opts.outWidth>requestWidth){
if(opts.outWidth>opts.outHeight){
inSampleSize=Math.round((float)opts.outHeight
/(float)requestHeight);
}else{
inSampleSize=Math.round((float)opts.outWidth
/(float)requestWidth);
}
}
opts.inSampleSize=inSampleSize;
opts.inJustDecodeBounds=false;//由于已经得到了缩放比例,让位图工厂真正的解析这个位图
//由于前面我们已经解析了这个输入流,需要重新初始化这个输入流
Bitmapbmp=BitmapFactory
.decodeByteArray(_data,0,_data.length,opts);
returnbmp;
}
//touch事件
privateOnTouchListenermTouchListener=newOnTouchListener(){
intstartx=0;
intstarty=0;
@Override
publicbooleanonTouch(Viewv,MotionEventevent){
switch(event.getAction()){
caseMotionEvent.ACTION_DOWN://手指第一次触摸屏幕
startx=(int)event.getX();
starty=(int)event.getY();
break;
caseMotionEvent.ACTION_MOVE://手指在imageview上中移动
intx=(int)event.getX();
inty=(int)event.getY();
mCanvas.drawLine(startx,starty,x,y,mPaint);
startx=(int)event.getX();
starty=(int)event.getY();
image.invalidate();
break;
}
returntrue;
}
};
}
希望本文所述对大家Android程序设计有所帮助。