这里实现下载进度条按钮的一个简单效果，主要是了解自定义View的一些常用的方法，drawRoundRect（），drawText（）等，下面是代码块
public classProgressButtonextendsTextView {
private static finalStringTAG="ProgressButton";
PaintmPaint,mTextPaint;
private intwidth,height,space,radius,progress;
private intprogressbtn_backgroud_color,progressbtn_backgroud_second_color;
//动画执行100.
private booleanisStart=false;
privateStringtext;
publicProgressButton(Context context) {
super(context);
}
publicProgressButton(Context context,@NullableAttributeSet attrs) {
super(context,attrs);
initPaint();
}
publicProgressButton(Context context,@NullableAttributeSet attrs, intdefStyleAttr) {
super(context,attrs,defStyleAttr);
}
private voidinitPaint() {
mPaint=newPaint();
progressbtn_backgroud_color= getContext().getResources().getColor(R.color.progressbtn_backgroud_color);
progressbtn_backgroud_second_color= getContext().getResources().getColor(R.color.progressbtn_backgroud_second_color);
mPaint.setColor(progressbtn_backgroud_color);
mPaint.setAntiAlias(true);
radius= DisplayUtil.dip2px(getContext(),8);
//文字画笔
mTextPaint=newPaint();
mTextPaint.setColor(Color.WHITE);
mTextPaint.setAntiAlias(true);
mTextPaint.setTextSize(DisplayUtil.sp2px(getContext(),14));
}
@Override
protected voidonDraw(Canvas canvas) {
super.onDraw(canvas);
//背景
mPaint.setColor(progressbtn_backgroud_color);
RectF r1 =newRectF(0,0,width,height);
canvas.drawRoundRect(r1,radius,radius,mPaint);
//进度
mPaint.setColor(progressbtn_backgroud_second_color);
intnewWidth =progress*space;
if(newWidth >=width) {
newWidth =width;
}
RectF r2 =newRectF(0,0,newWidth,height);
canvas.drawRoundRect(r2,radius,radius,mPaint);
//字体
if(progress==0) {
text="开始";
}else if(progress>=100) {
text="结束";
}else{
text="下载中 "+progress+" % ";
}
//获取文字的高宽
Rect rect =newRect();
mTextPaint.getTextBounds(text,0,text.length(),rect);
inttextWidth = rect.width();//文本的宽度
canvas.drawText(text,(width- textWidth) /2,height/2,mTextPaint);
postDelayed(runnable,30);
}
privateRunnablerunnable=newRunnable() {
@Override
public voidrun() {
if(!isStart) {
return;
}
if(progress>100) {
return;
}
progress++;
postInvalidate();
}
};
public voidstart() {
//进度
isStart=true;
post(runnable);
}
public voidpause() {
//进度
isStart=false;
post(runnable);
}
@Override
protected voidonSizeChanged(intw, inth, intoldw, intoldh) {
super.onSizeChanged(w,h,oldw,oldh);
width= w;
height= h;
space=width%100==0? w /100: (w /100) +1;
}
@Override
protected voidonFinishInflate() {
super.onFinishInflate();
setOnClickListener(newOnClickListener() {
@Override
public voidonClick(View view) {
if(isStart) {
pause();
}else{
start();
}
}
});
}
@Override
protected voidonDetachedFromWindow() {
super.onDetachedFromWindow();
if(runnable!=null) {
removeCallbacks(runnable);
}
}
}
项目地址：gitee.com/401328080/ProgressButton