android自定义view

package com.bawei.brush;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.view.View;

public class Line extends View {

public Line(Context context) {
super(context);
// TODO Auto-generated constructor stub
}

public Line(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
}

public Line(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
// TODO Auto-generated constructor stub
}

@Override
protected void onDraw(Canvas canvas) {
// TODO Auto-generated method stub
super.onDraw(canvas);
Paint paint = new Paint();//定义画笔
paint.setColor(Color.RED);//画笔红色
paint.setTextSize(20);//字体大小
paint.setStrokeWidth(20);//设置线宽
canvas.drawColor(Color.BLUE);//画板蓝色
canvas.drawLine(20, 20, 200, 200, paint);//直线 1.开始X 2.开始Y 3.结束X 4.结束Y 5.画笔
canvas.drawText("我是被画出来的", 10, 100, paint);//文字 1.显示文字 2.开始X 3.开始Y 4.画笔
canvas.drawCircle(55, 55, 50, paint);//圆 1.圆心X 2.圆心Y 3.半径 4.画笔
}

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
// TODO Auto-generated method stub
setMeasuredDimension(200, 200);//画板宽高
// super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}

}

<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"
tools:context=".MainActivity" >

<com.bawei.brush.Line
android:layout_width="wrap_content"
android:layout_height="wrap_content" />

</RelativeLayout>

package com.bawei.brush;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;

public class Drawview extends View{
public float X=30;//刚进入位置
public float Y=30;

public Drawview(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
}
@Override
protected void onDraw(Canvas canvas) {
// TODO Auto-generated method stub
super.onDraw(canvas);
Paint paint=new Paint();//定义画笔
paint.setColor(Color.RED);//画笔颜色
canvas.drawCircle(X, Y, 20, paint);//画小球

}

@Override
public boolean onTouchEvent(MotionEvent event) {
// TODO Auto-generated method stub
//当前组件的X,Y
this.X=event.getX();
this.Y=event.getY();
//通知该组件重绘
this.invalidate();

return true;

}
}

<LinearLayout 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.bawei.brush.Drawview
android:id="@+id/tt"
android:layout_width="match_parent"
android:layout_height="match_parent"

/>

</LinearLayout>

package com.bawei.brush;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PorterDuffXfermode;
import android.graphics.Rect;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.view.View;
import android.widget.ImageView;

/**
* * 自定义的圆形ImageView，可以直接当组件在布局中使用。
*
* @author caizhiming
* */
public class XCRoundImageView extends ImageView {
private Paint paint;

public XCRoundImageView(Context context) {
this(context, null);
}

public XCRoundImageView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}

public XCRoundImageView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
paint = new Paint();

}

@Override
protected void onDraw(Canvas canvas) {
// TODO Auto-generated method stub
Drawable drawable = getDrawable();

if (drawable == null) {

return;

}

if (getWidth() == 0 || getHeight() == 0) {

return;

}

Bitmap b = ((BitmapDrawable) drawable).getBitmap();

if (null == b)

{

return;

}
Bitmap bitmap = b.copy(Bitmap.Config.ARGB_8888, true);

// //获取图片的宽 高

int w = getWidth(), h = getHeight();

// 通过getCroppedBitmap函数，返回一个圆形图片

Bitmap roundBitmap = getCroppedBitmap(bitmap, w);

// 在自定义的CircleImageEx上展现

canvas.drawBitmap(roundBitmap, 0, 0, null);
/* super.onDraw(canvas); */

}

public static Bitmap getCroppedBitmap(Bitmap bmp, int radius) {
Bitmap p;
// 判断图片的大小与传入radius是否相等，如果不相等，那么

// 将图片设置成长 宽都是radius的图片

if (bmp.getWidth() != radius || bmp.getHeight() != radius)

p = Bitmap.createScaledBitmap(bmp, radius, radius, false);

else

p = bmp;

// 最后输出的图片信息

Bitmap output = Bitmap.createBitmap(p.getWidth(),

p.getHeight(), Config.ARGB_8888);

Canvas canvas = new Canvas(output);

final int color = 0xffa19774;

final Paint paint = new Paint();

final Rect rect = new Rect(0, 0, p.getWidth(), p.getHeight());

// 画笔加上 抗锯齿标志，图像更加平滑

paint.setAntiAlias(true);

// 如果该项设置为true,则图像在动画进行中会滤掉对Bitmap图像的优化操作,加快显示

paint.setFilterBitmap(true);

// 防抖动

paint.setDither(true);

// 透明色

canvas.drawARGB(0, 0, 0, 0);

// 画笔的颜色

paint.setColor(Color.parseColor("#BAB399"));

// 画出一个圆形

canvas.drawCircle(p.getWidth() / 2, p.getHeight() / 2,

p.getWidth() / 2 + 0.1f, paint);

// 设置两张图片相交时的模式 ，就是在画布上遮上圆形的图片信息

paint.setXfermode(new PorterDuffXfermode(
android.graphics.PorterDuff.Mode.SRC_IN));

canvas.drawBitmap(p, rect, rect, paint);

return output;

}

}

<LinearLayout 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"
android:orientation="vertical" >

<com.bawei.brush.XCRoundImageView
android:id="@+id/roundImageView"
android:layout_width="50dp"
android:layout_height="50dp"
android:layout_centerInParent="true"
android:src="@drawable/butterfly" />

</LinearLayout>