2023学年完整公开课版Bitmap类

《通信业务开发》课程Bitmap位图BitmapPART21-42D绘图功能特性属性方法实例演示View画框，装裱图画，展示在Activity中1234Canvas画布，提供绘图方法Paint画笔，可设置粗细、颜色、风格样式…Color颜料色彩根据ARGB调配色彩，供画笔使用5BitmapPathDrawableMatrix……图片、图形、路径、矩阵等其他工具…2D绘图功能特性示例android.graphics.Bitmap位图专用对图片资源获取、剪切、旋转、缩放、转换格式保存等操作必须配合android.graphics.BitmapFactoryBitmapFactory是一个工具类用于从不同数据源解析、创建Bitmap对象特性No.方法类型描述1publicstaticBitmapcreateBitmap(Bitmapsrc)普通复制一个Bitmap2publicstaticBitmapcreateBitmap(Bitmapsource,intx,inty,intwidth,intheight,Matrixm,booleanfilter)普通对Bitmap进行剪切3publicfinalintgetHeight()普通取得图像的高4publicfinalintgetWidth()普通取得图像的宽5publicstaticBitmapcreateScaledBitmap(Bitmapsrc,intdstWidth,intdstHeight,booleanfilter)普通创建指定大小BitmapBitmap1属性方法No.方法类型描述1publicstaticBitmapdecodeByteArray(byte[]data,intoffset,intlength)普通根据指定数据文件创建Bitmap2publicstaticBitmapdecodeFile(StringpathName)普通根据指定路径创建Bitmap3publicstaticBitmapdecodeResource(Resourcesres,intid)普通根据指定资源创建Bitmap4publicstaticBitmapdecodeStream(InputStreamis)普通根据指定InputStream创建BitmapBitmapFactory2属性方法实例演示publicclassImageAcextendsActivityimplementsOnClickListener{ImageViewsrc,dst;Buttonmirror,flip,saturation,bright,contrast;@OverridepublicvoidonCreate(BundlesavedInstanceState){super.onCreate(savedInstanceState);setContentView(R.layout.imageac);src=(ImageView)findViewById(R.id.imagesrc);dst=(ImageView)findViewById(R.id.imagedst);mirror=(Button)findViewById(R.id.mirror);flip=(Button)findViewById(R.id.flip);saturation=(Button)findViewById(R.id.saturation);bright=(Button)findViewById(R.id.bright);contrast=(Button)findViewById(R.id.contrast);mirror.setOnClickListener(this);flip.setOnClickListener(this);saturation.setOnClickListener(this);bright.setOnClickListener(this);contrast.setOnClickListener(this);}publicvoidonClick(Viewv){BitmapdstImage=null;switch(v.getId()){caseR.id.mirror:dstImage=mirrorBitmap();break;caseR.id.flip:dstImage=flipBitmap();break;caseR.id.saturation:dstImage=saturationBitmap();break;caseR.id.bright:dstImage=brightBitmap();break;caseR.id.contrast:dstImage=constrastBitmap();break;}dst.setImageBitmap(dstImage);}}Activity事件响应1实例演示//得到镜像后的图片publicBitmapmirrorBitmap(){Bitmapsrc=BitmapFactory.decodeResource(getResources(),R.drawable.ava);Bitmapcopy=Bitmap.createBitmap(src.getWidth(),src.getHeight(),src.getConfig());Canvascanvas=newCanvas(copy);Paintpaint=newPaint();Matrixm=newMatrix();m.setScale(-1,1);m.postTranslate(src.getWidth(),0);canvas.drawBitmap(src,m,paint);returncopy;}镜像矩阵变化2实例演示//得到倒影后的图片publicBitmapflipBitmap(){Bitmapsrc=BitmapFactory.decodeResource(getResources(),R.drawable.ava);Bitmapflip=Bitmap.createBitmap(src.getWidth(),src.getHeight(),src.getConfig());Canvascanvas=newCanvas(flip);Paintpaint=newPaint();Matrixm=newMatrix();m.setScale(1,-1);m.postTranslate(0,src.getHeight());canvas.drawBitmap(src,m,paint);returnflip;}倒影矩阵变换3实例演示//得到RGBA变化后的图片publicBitmapconstrastBitmap(){Bitmapsrc=BitmapFactory.decodeResource(getResources(),R.drawable.ava);Bitmapdst=Bitmap.createBitmap(src.getWidth(),src.getHeight(),src.getConfig());Canvascanvas=newCanvas(dst);Paintpaint=newPaint();

ColorMatrixm=newColorMatrix();floatr=2,g=2,b=2,a=1;m.set(newfloat[]{r,0,0,0,0,0,g,0,0,0,0,0,b,0,0,0,0,0,a,0,});ColorMatrixColorFiltercmcf=newColorMatrixColorFilter(m);paint.setColorFilter(cmcf);canvas.drawBitmap(src,0,0,paint);returndst;}RGBA矩阵变换4实例演示//得到变亮后的图片publicBitmapbrightBitmap(){Bitmapsrc=BitmapFactory.decodeResource(getResources(),R.drawable.ava);Bitmapdst=Bitmap.createBitmap(src.getWidth(),src.getHeight(),src.getConfig());Canvascanvas=newCanvas(dst);Paintpaint=newPaint();ColorMatrixm=newColorMatrix();floatr=2,g=2,b=2,br=50;m.set(newfloat[]{r,0,0,0,br,0,g,0,0,br,0,0,b,0,br,0,0,0,1,0,});ColorMatrixColorFiltercmcf=newColorMatrixColorFilter(m);paint.setColorFilter(cmcf);canvas.drawBitmap(src,0,0,paint);returndst;}亮度变换矩阵5实例演示//得到变化饱和度后的图片publicBitmapsaturationBitmap(){Bitmapsrc=BitmapFactory.decodeResource(getResources(),R.drawable.ava);Bitmapdst=Bitmap.createBitmap(src.getWidth(),src.getHeight(),src.getConfig());Canvascanvas=newCanvas(dst);Paintpaint=newPaint();ColorMatrixm=newColorMatrix();floatr=1,g=1,b=1,