自定义View之继承View-蒲公英云

自定义View之继承View

效果图，点击按钮增加圆圈

自定义View源代码

package com.example.administrator.youku_animi.MyView;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.view.View;
import android.view.WindowManager;
/** * Created by Administrator on 2017/7/24 0024. */
public class NewView extends View { 
    int mWindowWidth;
    //中心点
    int mCircleXY ;
    float mSweepAngle = 25f;
    float mRadius;
    RectF mArcRectF;
    Paint mCirclePaint, mArcPaint, mTextPaint;
    String mShowText; 
    int mShowTextSize;
    public NewView(Context context, AttributeSet attrs)
    {
        super(context, attrs);
        WindowManager wm = (WindowManager) getContext()
                .getSystemService(Context.WINDOW_SERVICE);
        mWindowWidth = wm.getDefaultDisplay().getWidth();
        mCircleXY = mWindowWidth / 2;
        mRadius = (float) (mWindowWidth*0.5/2) ;
        mShowText = "It 's OK";
        mShowTextSize = mShowText.length();
        mArcRectF = new RectF(
                (float)(mWindowWidth*0.2),
                (float)(mWindowWidth*0.2),
                (float)(mWindowWidth*0.8),
                (float)(mWindowWidth*0.8)
        );
        mCirclePaint = new Paint();
        //给画笔设置颜色
        mCirclePaint.setColor(getResources().getColor(android.R.color.holo_blue_bright));
        mCirclePaint.setStyle(Paint.Style.FILL);
        mCirclePaint.setStrokeWidth(4);
        mArcPaint= new Paint();
        mArcPaint.setColor(getResources().getColor(android.R.color.holo_red_dark));
        mArcPaint.setStyle(Paint.Style.STROKE);
        mArcPaint.setStrokeWidth(20);
        mTextPaint = new Paint();
        mTextPaint.setColor(getResources().getColor(android.R.color.secondary_text_light));
        mTextPaint.setStyle(Paint.Style.STROKE);
        //设置画笔粗细
        mTextPaint.setStrokeWidth(1);
        //设置文字居中
        mTextPaint.setTextAlign(Paint.Align.CENTER);
        //设置抗锯齿
        mTextPaint.setAntiAlias(true);
        //设置文字大小
        mTextPaint.setTextSize(100);
    }
    @Override
    protected void onDraw(Canvas canvas)
    {
        //绘制圆
        canvas.drawCircle(mCircleXY, mCircleXY, mRadius, mCirclePaint);
        //绘制弧线
        canvas.drawArc(mArcRectF, 270, mSweepAngle, false, mArcPaint);
        //绘制文字
        canvas.drawText(mShowText, 0, mShowTextSize,
                mCircleXY, mCircleXY + (mShowTextSize / 4), mTextPaint);
// canvas.save();
        super.onDraw(canvas);
// canvas.restore();
    }
    //改变外圆的角度
    public void setmSweepValue(float sweepValue)
    {
        if (sweepValue != 0)
        {
            mSweepAngle += 5;
        }
        else
        {
            mSweepAngle = 25;
        }
        this.invalidate();
    }
}

xml布局文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:newview="http://schemas.android.com/apk/res-auto" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent">
    <com.example.administrator.youku_animi.MyView.NewView android:id="@+id/newview_test" android:layout_width="match_parent" android:layout_height="500dp" />
    <Button android:id="@+id/btn" android:text="click" android:layout_width="match_parent" android:layout_height="wrap_content" />
</LinearLayout>

Activity..

package com.example.administrator.youku_animi;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import com.example.administrator.youku_animi.MyView.NewView;
/** * Created by Administrator on 2017/7/24 0024. */
public class NewViewTest extends Activity { 
    NewView newView;
    Button button;
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.new_view_test);
        newView = (NewView) findViewById(R.id.newview_test);
        button = (Button) findViewById(R.id.btn);
        button.setOnClickListener(new View.OnClickListener()
        {
            @Override
            public void onClick(View view)
            {
                newView.setmSweepValue(1);
            }
        });
    }
}