根据输入框的值生成圆环效果

先看布局:

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical" >    <LinearLayout         android:layout_width="match_parent"        android:layout_height="wrap_content"        >        <TextView             android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:text="圆环的半径:"            />        <EditText             android:id="@+id/et_rediu"            android:layout_width="match_parent"            android:layout_height="wrap_content"            />    </LinearLayout>    <LinearLayout         android:layout_width="match_parent"        android:layout_height="wrap_content"        >        <TextView             android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:text="圆环的宽度:"            />        <EditText             android:id="@+id/et_width"            android:layout_width="match_parent"            android:layout_height="wrap_content"            />    </LinearLayout>    <LinearLayout         android:layout_width="match_parent"        android:layout_height="wrap_content"        >        <TextView             android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:text="圆环的颜色:"            />        <EditText             android:id="@+id/et_color"            android:layout_width="match_parent"            android:layout_height="wrap_content"            />    </LinearLayout>    <Button         android:id="@+id/bt_shengcheng"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="生成的圆环展示"        />        <com.bwie.test.CircleImageView        android:id="@+id/img"        android:layout_width="300dp"        android:layout_height="300dp"        android:layout_gravity="center_horizontal"        ></com.bwie.test.CircleImageView>    </LinearLayout>

再看自定义View上的代码:

package com.bwie.test;import android.content.Context;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.util.AttributeSet;import android.widget.ImageView;public class CircleImageView extends ImageView{private final  Paint paint;private final Context context;private int banjing = 100;private int width = 30;private String color = "#ff0000";public CircleImageView(Context context) {// TODO Auto-generated constructor stubthis(context, null);}public CircleImageView(Context context, AttributeSet attrs) {super(context, attrs);// TODO Auto-generated constructor stubthis.context = context;this.paint = new Paint();this.paint.setAntiAlias(true); //消除锯齿this.paint.setStyle(Paint.Style.STROKE); //绘制空心圆 }@Overrideprotected void onDraw(Canvas canvas) {// TODO Auto-generated method stubint center = getWidth()/2;int innerCircle = dip2px(context, banjing); //设置内圆半径int ringWidth = dip2px(context, width); //设置圆环宽度//绘制内圆this.paint.setARGB(255, 212 ,225, 233);this.paint.setStrokeWidth(2);canvas.drawCircle(center,center, innerCircle, this.paint);//绘制圆环this.paint.setColor(Color.parseColor(color));this.paint.setStrokeWidth(ringWidth);canvas.drawCircle(center,center, innerCircle+1+ringWidth/2, this.paint);//绘制外圆this.paint.setARGB(155, 167, 190, 206);this.paint.setStrokeWidth(2);canvas.drawCircle(center,center, innerCircle+ringWidth, this.paint);super.onDraw(canvas);}public void circleChange(int banjing,int width,String color){this.banjing = banjing;this.color = color;this.width = width;postInvalidate();//重新绘制}/** * 根据手机的分辨率从 dp 的单位 转成为 px(像素) */public static int dip2px(Context context, float dpValue) {final float scale = context.getResources().getDisplayMetrics().density;return (int) (dpValue * scale + 0.5f);}}

再就是Fragment上的代码:

package com.bwie.fragments;import com.bwie.test.CircleImageView;import com.bwie.test.R;import android.os.Bundle;import android.support.annotation.Nullable;import android.support.v4.app.Fragment;import android.view.LayoutInflater;import android.view.View;import android.view.View.OnClickListener;import android.view.ViewGroup;import android.widget.Button;import android.widget.EditText;import android.widget.ImageView;public class ZidingyiFragment extends Fragment {    private EditText rediu;private EditText width;private EditText color;private CircleImageView img;private Button shengcheng;@Overridepublic View onCreateView(LayoutInflater inflater,@Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {View view=inflater.inflate(R.layout.fra1_zidingyi, null);rediu=(EditText)view.findViewById(R.id.et_rediu);width=(EditText)view.findViewById(R.id.et_width);color=(EditText)view.findViewById(R.id.et_color);img=(CircleImageView)view.findViewById(R.id.img);shengcheng=(Button)view.findViewById(R.id.bt_shengcheng);shengcheng.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View v) {String redius=rediu.getText().toString();String widths=width.getText().toString();String colors=color.getText().toString();img.circleChange(Integer.parseInt(redius),Integer.parseInt(widths),colors);}});return view;}}