（安卓） 自定义View 绘画圆（包括简单的接口回调）

上图：

    这道题主要是  当点击Button按钮的时候 开始走进度条  ，当进度条走到100时  跳转到第二个页面

上代码：

 xml类：

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:app="http://schemas.android.com/apk/res-auto"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical"    tools:context="bawe.day1105lianximoni.MainActivity">   <bawe.day1105lianximoni.ProgressView       android:layout_width="400dp"       android:layout_height="200dp"       android:id="@+id/pv_data"       />   <Button       android:layout_width="match_parent"       android:layout_height="wrap_content"       android:text="点击我"       android:id="@+id/bt_one"       /></LinearLayout>

MainActivity 类：

package bawe.day1105lianximoni;import android.content.Intent;import android.os.Bundle;import android.os.Handler;import android.os.Message;import android.support.v7.app.AppCompatActivity;import android.view.View;import android.widget.Button;public class MainActivity extends AppCompatActivity {    private Button bt_one;    private ProgressView pv;    //定义一个静态的常量    private static final int FLAG = 0x123;    private Handler handler = new Handler() {        @Override        public void handleMessage(Message msg) {            super.handleMessage(msg);            switch (msg.what) {                //指定在同一个频道                case FLAG:                    int progress = pv.getProgress();                    progress += 10;                    if (progress > 100) {                        progress = 0;                    }                    //更新当前的进度值                    pv.setProgress(progress);                    //指定在同一个频道   FLAG                    handler.sendEmptyMessageDelayed(FLAG, 1000);                    break;            }        }    };    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        bt_one = (Button) findViewById(R.id.bt_one);        pv = (ProgressView) findViewById(R.id.pv_data);        bt_one.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View view) {                handler.sendEmptyMessageDelayed(FLAG, 1000);            }        });        //接口的方法         pv.setListener(new ProgressView.ProhressUpdateListener() {             @Override             public void onProgressUpdated(int progress) {                 //如果当前的进度等于100                 if (progress>=100){                     //就进行跳转                     startActivity(new Intent(MainActivity.this,Main2Activity.class));                 }             }         });    }  =============================================================================  

ProgressView类：

package bawe.day1105lianximoni;import android.content.Context;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graphics.Rect;import android.support.annotation.Nullable;import android.util.AttributeSet;import android.view.View;import static android.R.attr.radius;/** * Created by 迷人的脚毛！！ on 2017/11/5. */public class ProgressView extends View{    //接口对象    private ProhressUpdateListener listener;    //定义一个接口    interface ProhressUpdateListener{        void onProgressUpdated(int progress);    }    //对外提供一个set方法    public void setListener(ProhressUpdateListener listener) {        this.listener = listener;    }    //设置角度为0    private int progress=0;    public ProgressView(Context context) {        super(context);    }    public ProgressView(Context context, @Nullable AttributeSet attrs) {        super(context, attrs);    }    public ProgressView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {        super(context, attrs, defStyleAttr);    }//Progress  get和set方法    public int getProgress() {        return progress;    }    public void setProgress(int progress) {        this.progress = progress;        //重新刷新一下        postInvalidate();        if (listener!=null){            //当前的进度            listener.onProgressUpdated(progress);        }    }    @Override    protected void onDraw(Canvas canvas) {        super.onDraw(canvas);        int width = getWidth();        int height = getHeight();        //绘制范围        int min = Math.min(width, height);        //半径        int i = min / 2;        //绘制外层最大的圆        Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);        paint.setColor(Color.BLUE);        paint.setStyle(Paint.Style.STROKE);        canvas.drawCircle(i,i,i,paint);        //重置        paint.reset();        paint.setStyle(Paint.Style.STROKE);        paint.setColor(Color.RED);        //设置图形的边框厚度        paint.setStrokeWidth(20);       //绘画扇形        canvas.drawArc(10, 10, min-10, min-10, -90, progress*360/100, true, paint);        //重置        paint.reset();        //设置颜色        paint.setColor(Color.WHITE);        //设置实心        paint.setStyle(Paint.Style.FILL_AND_STROKE);        canvas.drawCircle(i,i,i-20,paint);        // 画进度文字        paint.reset();        paint.setColor(Color.BLUE);        paint.setTextSize(40);        Rect rect = new Rect();        paint.getTextBounds(progress + "", 0, String.valueOf(progress).length(),                rect);        int textWidth = rect.width();        int textHeight = rect.height();        canvas.drawText(progress + "", i-textWidth/2, i-textHeight/2, paint);    }}

这个代码里面包裹了绘圆，绘画扇形， 绘画进度文字