android开发分享android 自定义圆角button效果的实例代码（自定义view Demo）

  /**   * author: xujiajia   * description:   * 1、drawable只有在设置textstring的时候才会生效(居中效果两个一起测量)   */  public class roundradiusbutton extends view {   //data   private int width = 0;   private int height = 0;   private int roundradius = 16;   private int bgcolor = color.ltgray;   private boolean istouching = false;   //img and text   private drawable leftdrawable = null;   private int drawablewidth = 20;   private int drawableheight = 20;   private int leftdrawablepaddingright = 0;   private string textstring;   private int textsize = 30;   private int textcolor = color.black;   //ondraw   paint paint;   path path;   rectf rectf;   rect rect;   public roundradiusbutton(context context, int width, int height) {   super(context);   this.width = width;   this.height = height;   this.setlayoutparams(new viewgroup.layoutparams(width, height));   this.setclickable(true);   }   public roundradiusbutton(context context, attributeset attrs) {   super(context, attrs);   getdatafromattrs(context, attrs);   this.setclickable(true);   }   public roundradiusbutton(context context, attributeset attrs, int defstyleattr) {   super(context, attrs, defstyleattr);   getdatafromattrs(context, attrs);   this.setclickable(true);   }   private void getdatafromattrs(context context, attributeset attrs) {   if (attrs == null) {   return;   }   typedarray ta = context.obtainstyledattributes(attrs, r.styleable.roundradiusbutton);   roundradius = ta.getdimensionpixeloffset(r.styleable.roundradiusbutton_roundradius, 16);   bgcolor = ta.getcolor(r.styleable.roundradiusbutton_bgcolor, color.ltgray);   leftdrawable = ta.getdrawable(r.styleable.roundradiusbutton_leftdrawable);   drawablewidth = ta.getdimensionpixeloffset(r.styleable.roundradiusbutton_drawablewidth, 0);   drawableheight = ta.getdimensionpixeloffset(r.styleable.roundradiusbutton_drawableheight, 0);   leftdrawablepaddingright =   ta.getdimensionpixeloffset(r.styleable.roundradiusbutton_leftdrawablepaddingright, 0);   textstring = ta.getstring(r.styleable.roundradiusbutton_textstring);   textsize = ta.getdimensionpixeloffset(r.styleable.roundradiusbutton_textsize, 0);   textcolor = ta.getcolor(r.styleable.roundradiusbutton_textcolor, color.black);   ta.recycle();   }   public void setroundradius(int roundradius) {   this.roundradius = roundradius;   invalidate();   }   public void setbgcolor(int bgcolor) {   this.bgcolor = bgcolor;   invalidate();   }   public void setleftdrawable(drawable leftdrawable, int drawablewidth, int drawableheight,   int paddingright) {   this.leftdrawable = leftdrawable;   this.drawablewidth = drawablewidth;   this.drawableheight = drawableheight;   this.leftdrawablepaddingright = paddingright;   invalidate();   }   public void settextstring(string textstring) {   this.textstring = textstring;   invalidate();   }   public void settextcolor(int textcolor) {   this.textcolor = textcolor;   invalidate();   }   public void settextsize(int textsize) {   this.textsize = textsize;   invalidate();   }   @override public boolean ontouchevent(motionevent event) {   if (isclickable()) {   switch (event.getaction()) {   case motionevent.action_down:    istouching = true;    invalidate();    break;   case motionevent.action_up:    istouching = false;    invalidate();    break;   }   }   return super.ontouchevent(event);   }   @override protected void ondraw(canvas canvas) {   super.ondraw(canvas);   if (width == 0 || height == 0) {   width = getwidth();   height = getheight();   }   if (paint == null) {   paint = new paint();   }   if (path == null) {   path = new path();   }   if (rectf == null) {   rectf = new rectf();   }   if (rect == null) {   rect = new rect();   }   paint.setcolor(bgcolor);   paint.setantialias(true);//抗锯齿   paint.setstrokewidth(0);//线的宽度设为0，避免画圆弧的时候部分圆弧与边界相切   paint.setstyle(paint.style.fill_and_stroke);   path.setfilltype(path.filltype.winding);   //左上圆角   path.moveto(0, roundradius);   rectf.set(0, 0, 2 * roundradius,   2 * roundradius);   path.addarc(rectf, 180, 90);   //上边   path.lineto(width - roundradius, 0);   //右上圆角   rectf.set(width - roundradius * 2, 0, width, roundradius * 2);   path.addarc(rectf, -90, 90);   //右边   path.lineto(width, height - roundradius);   //右下圆角   rectf.set(width - roundradius * 2, height - roundradius * 2, width,   height);   path.addarc(rectf, 0, 90);   //下边   path.lineto(roundradius, height);   //左下圆角   rectf.set(0, height - roundradius * 2, 2 * roundradius,   height);   path.addarc(rectf, 90, 90);   //左边   path.lineto(0, roundradius);   path.close();   canvas.drawpath(path, paint);   if (istouching) {   paint.setcolor(getcontext().getresources().getcolor(r.color.black_tran_30));   canvas.drawpath(path, paint);   }   //填充背景中间空白的部分   path.moveto(0, roundradius);   path.lineto(width - roundradius, 0);   path.lineto(width, height - roundradius);   path.lineto(roundradius, height);   path.close();   canvas.drawpath(path, paint);   if (istouching) {   paint.setcolor(getcontext().getresources().getcolor(r.color.black_tran_30));   canvas.drawpath(path, paint);   }   //text, drawable两个一起计算位置   if (!textutils.isempty(textstring)) {   paint.setstrokewidth(1.5f);   paint.setcolor(textcolor);   paint.settextsize(textsize);   rect.setempty();   paint.gettextbounds(textstring, 0, textstring.length(), rect);   float leftbitmap = 0;   float topbitmap = 0;   if (leftdrawable != null) {   if (leftdrawable != null) {    leftbitmap = (1.0f * width - drawablewidth - rect.width() - leftdrawablepaddingright) / 2;    topbitmap = (1.0f * height - drawableheight) / 2;    leftdrawable.setbounds((int) leftbitmap, (int) topbitmap,    (int) (leftbitmap + drawablewidth),    (int) (topbitmap + drawableheight));    leftdrawable.draw(canvas);   }   }   float textx = 0;   float texty =    1.0f * height / 2 + paint.gettextsize() / 2 - paint.getfontmetrics().descent / 2;   if (leftbitmap == 0 && topbitmap == 0) {   textx = width / 2 - rect.width() / 2;   } else {   textx = leftbitmap + drawablewidth + leftdrawablepaddingright;   }   canvas.drawtext(textstring, textx, texty, paint);   }   }  }

  public class mainactivity extends appcompatactivity {   private linearlayout llcontainer;   @override   protected void oncreate(bundle savedinstancestate) {   super.oncreate(savedinstancestate);   setcontentview(r.layout.activity_main);   initview();   }   private void initview() {   llcontainer = findviewbyid(r.id.ll_container);   roundradiusbutton roundradiusbutton = new roundradiusbutton(this, 500, 200);   roundradiusbutton.setbgcolor(color.ltgray);   roundradiusbutton.setroundradius(40);   //text   roundradiusbutton.settextstring("testtesttest");   roundradiusbutton.settextcolor(color.white);   roundradiusbutton.settextsize(40);   //drawable   roundradiusbutton.setleftdrawable(getresources().getdrawable(r.mipmap.ic_launcher), 60, 60, 80);   roundradiusbutton.setonclicklistener(new view.onclicklistener() {   @override public void onclick(view v) {   toast.maketext(mainactivity.this, "testest", toast.length_long).show();   }   });   roundradiusbutton.setclickable(false);   llcontainer.addview(roundradiusbutton);   }  }

  <?xml version="1.0" encoding="utf-8"?>  <linearlayout xmlns:android="https://schemas.android.com/apk/res/android"   xmlns:app="https://schemas.android.com/apk/res-auto"   xmlns:tools="https://schemas.android.com/tools"   android:id="@+id/ll_container"   android:layout_width="match_parent"   android:layout_height="match_parent"   android:background="#868684"   android:gravity="center"   android:orientation="vertical"   tools:context=".mainactivity"   >   <com.example.newbuttiontest.roundradiusbutton   android:layout_width="300dp"   android:layout_height="200dp"   app:bgcolor="#ffeb3b"   app:drawableheight="18dp"   app:drawablewidth="18dp"   app:leftdrawable="@mipmap/ic_launcher"   app:leftdrawablepaddingright="5dp"   app:roundradius="30dp"   app:textcolor="#ff4329"   app:textsize="16dip"   app:textstring="testtesttest"   />  </linearlayout>

  <?xml version="1.0" encoding="utf-8"?>  <resources>   <declare-styleable name="roundradiusbutton">   <attr name="roundradius" format="dimension" />   <attr name="bgcolor" format="color" />   <attr name="leftdrawable" format="reference" />   <attr name="leftdrawablepaddingright" format="dimension" />   <attr name="drawablewidth" format="dimension" />   <attr name="drawableheight" format="dimension" />   <attr name="textstring" format="string" />   <attr name="textsize" format="dimension" />   <attr name="textcolor" format="color" />   </declare-styleable>  </resources>

  <resources>   <color name="black_tran_30">#30000000</color>  </resources>