自己写了个简单的demo
实现后的效果是这样的
这个demo是用了线程去发消息，然后ui线程中做了progressbar的更新显示
也可以用view.post(Runnable)去实现；或者onWindowsFocusedChanged去实现（此法，由于onPause与OnResum都会调用，太频繁）
直接上代码干货：
为自定义的progressbar
public class MyProgressBar extends View {
/**进度条最大值*/
private float maxCount;
/**进度条当前值*/
private float currentCount;
/**画笔*/
private Paint mPaint;
private int mWidth,mHeight;
publicMyProgressBar(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
publicMyProgressBar(Context context, AttributeSet attrs) {
super(context, attrs);
}
publicMyProgressBar(Context context) {
super(context);
}
/***
*设置最大的进度值
* @param maxCount
*/
public void setMaxCount(float maxCount) {
this.maxCount = maxCount;
Log.i("zhm","macout=="+maxCount);
}
/**
*得到最大进度值
*/
public double getMaxCount(){
return maxCount;
}
/***
*设置当前的进度值
* @param currentCount
*/
public void setCurrentCount(float currentCount) {
this.currentCount = currentCount > maxCount ? maxCount : currentCount;
Log.i("zhm","currentCount=="+currentCount);
/**
* invalidate()是用来刷新View的，必须是在UI线程中进行工作。比如在修改某个view的显示时，
*调用invalidate()才能看到重新绘制的界面。invalidate()的调用是把之前的旧的view从主UI
*线程队列中pop掉。
*/
invalidate();
}
@Override
protected void onDraw(Canvas canvas) {
//TODO Auto-generated method stub
super.onDraw(canvas);
Log.i("zhm","onDraw");
mPaint = new Paint();
//设置抗锯齿效果
mPaint.setAntiAlias(true);
//设置画笔颜色
mPaint.setColor(Color.BLACK);
int round = mHeight/2;
Log.i("zhm","round==="+round);
/**
* RectF：绘制矩形，四个参数分别是left,top,right,bottom
*类型是单精度浮点数
*/
RectF rf = new RectF(0, 0, mWidth, mHeight);
/*绘制圆角矩形，背景色为画笔颜色*/
canvas.drawRoundRect(rf, round, round, mPaint);
///*设置progress内部是灰色*/
mPaint.setColor(Color.rgb(211, 211, 211));
RectF rectBlackBg = new RectF(2, 2, mWidth-2, mHeight-2);
canvas.drawRoundRect(rectBlackBg, round, round, mPaint);
//设置进度条进度及颜色
float section = currentCount/maxCount;
Log.i("zhm","currentCount=="+currentCount+" ==maxCount===="+maxCount);
RectF rectProgressBg = new RectF(3, 3, (mWidth-3)*section, mHeight-3);
if(section!=0.0f){
mPaint.setColor(Color.GREEN);
}else{
mPaint.setColor(Color.TRANSPARENT);
}
canvas.drawRoundRect(rectProgressBg, round, round, mPaint);
}
//dip * scale + 0.5f * (dip >= 0 ? 1 : -1)
private int dipToPx(int dip){
float scale = getContext().getResources().getDisplayMetrics().density;
return (int) (dip * scale + 0.5f * (dip >= 0 ? 1 : -1));//加0.5是为了四舍五入
}
/**指定自定义控件在屏幕上的大小,onMeasure方法的两个参数是由上一层控件
*传入的大小，而且是模式和尺寸混合在一起的数值，需要MeasureSpec.getMode(widthMeasureSpec)
*得到模式，MeasureSpec.getSize(widthMeasureSpec)得到尺寸
*
*/
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
Log.i("zhm","onMeasure");
int widthSpecMode = MeasureSpec.getMode(widthMeasureSpec);
int heightSpecMode = MeasureSpec.getMode(heightMeasureSpec);
int widthSpecSize = MeasureSpec.getSize(widthMeasureSpec);
int heightSpecSize = MeasureSpec.getSize(heightMeasureSpec);
//MeasureSpec.EXACTLY，精确尺寸
if (widthSpecMode == MeasureSpec.EXACTLY|| widthSpecMode == MeasureSpec.AT_MOST) {
mWidth = widthSpecSize;
Log.i("zhm","mWidh==="+mWidth);
} else {
mWidth = 0;
}
//MeasureSpec.AT_MOST，最大尺寸，只要不超过父控件允许的最大尺寸即可，MeasureSpec.UNSPECIFIED未指定尺寸
if (heightSpecMode == MeasureSpec.AT_MOST|| heightSpecMode == MeasureSpec.UNSPECIFIED) {
mHeight = dipToPx(20);
Log.i("zhm","mHeight==="+mHeight);
} else {
mHeight = heightSpecSize;
Log.i("zhm","esle de mHeight==="+mHeight);
}
//设置控件实际大小
setMeasuredDimension(mWidth, mHeight);
}
}
如下为demo的activity：
public class ProgressBarTestActivity extends Activity {
private MyProgressBar progress;
private int total_length;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_progress_bar_test);
progress = (MyProgressBar) findViewById(R.id.pb);
progress.setMaxCount(100);
new Thread(new Runnable() {
@Override
public void run() {
// for (int i = 0; i <=progress.getMaxCount(); i++) {
Message msg = new Message();
int[] ar=calculateMethod("50","100");
msg.arg1 = ar[0];
msg.what = 0x01;
handler.sendMessage(msg);
try {
//每隔0.1秒进度前进1
Thread.sleep(100);
} catch (InterruptedException e) {
e.printStackTrace();
}
// }
}
}).start();
}
private int[] calculateMethod(String num1, String num2) {
int[] arr = new int[2];
try {
if (null == num1 || null == num2) {
return arr;
}
int newNum1 = Integer.parseInt(num1);
int newNum2 = Integer.parseInt(num2);
Log.i("zhm","newnum1=="+newNum1);
Log.i("zhm","newNum2=="+newNum2);
if (newNum1 != 0){
arr[0] = newNum1*100 / (newNum1 + newNum2);
Log.i("zhm"," !=0 arr[0]=="+arr[0]);
}else {
arr[0] = 0;
Log.i("zhm"," =0 arr[0]=="+arr[0]);
}
return arr;
} catch (Exception e) {
}
return arr;
}
Handler handler = new Handler(){
public void handleMessage(Message msg) {
if(msg.what==0x01){
progress.setCurrentCount(msg.arg1) ;
}
};
};
}