Android 自定义进度条

先看效果图吧

自定义View

public class CircleView extends View {

	private int maxProgress = 100;
	private int progress = 30;
	private int progressStrokeWidth = 4;
	// 画圆所在的距形区域
	RectF oval;
	Paint paint;

	public CircleView(Context context, AttributeSet attrs) {
		super(context, attrs);
		// TODO Auto-generated constructor stub
		oval = new RectF();
		paint = new Paint();
	}

	@Override
	protected void onDraw(Canvas canvas) {
		// TODO Auto-generated method stub
		super.onDraw(canvas);
		int width = this.getWidth() / 2;
		int height = this.getHeight() / 2;
		int len = this.getWidth() / 4;

		paint.setAntiAlias(true); // 设置画笔为抗锯齿
		paint.setColor(Color.WHITE); // 设置画笔颜色
		canvas.drawColor(Color.TRANSPARENT); // 白色背景
		paint.setStrokeWidth(progressStrokeWidth); // 线宽
		paint.setStyle(Style.STROKE);

		oval.left = width - len; // 左上角x
		oval.top = height - len; // 左上角y
		oval.right = width + len; // 右下角x
		oval.bottom = height + len; // 右下角y

		paint.setColor(Color.RED);
		canvas.drawArc(oval, -90, 360, false, paint); // 绘制白色圆圈，即进度条背景
		paint.setColor(Color.BLUE);
		canvas.drawArc(oval, -90, ((float) progress / maxProgress) * 360, false, paint); // 绘制进度圆弧，这里是蓝色

		paint.setStrokeWidth(1);
		String text = progress + "%";
		int textHeight = height / 10; // 设置字体高度
		paint.setTextSize(textHeight);
		int textWidth = (int) paint.measureText(text, 0, text.length());
		paint.setStyle(Style.FILL);
		canvas.drawText(text, this.getWidth() / 2 - textWidth / 2, this.getHeight() / 2 + textHeight / 2, paint);
	}

	public int getMaxProgress() {
		return maxProgress;
	}

	public void setMaxProgress(int maxProgress) {
		this.maxProgress = maxProgress;
	}

	public void setProgress(int progress) {
		this.progress = progress;
		this.invalidate();
	}

	/**
	 * 非ＵＩ线程调用
	 */
	public void setProgressNotInUiThread(int progress) {
		this.progress = progress;
		this.postInvalidate();
	}

}

MainActivity.class:

package com.example.customview;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;

public class MainActivity extends Activity {

	private CircleView circleView;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);

		circleView = (CircleView) findViewById(R.id.progressbar);
		// circleView.setProgressNotInUiThread(50);
		new Thread()
		{
			public void run()
			{
				int i = 0;
				while (i <= 100)
				{
					circleView.setProgressNotInUiThread(i);
					i++;
					try {
						sleep(100);
						if (i == 100)
							i = 0;
					} catch (InterruptedException e) {
						// TODO 自动生成的 catch 块
						e.printStackTrace();
					}
				}

			}
		}.start();

	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.main, menu);
		return true;
	}

}

activity_main.xml:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <com.example.customview.CircleView
        android:id="@+id/progressbar"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

</RelativeLayout>