SurfaceView使用
首先创建一个SurfaceViewSign类，继承SurfaceView类，继承 SurfaceHolder.Callback和Runnable接口，代码如下：
代码语言：javascript复制import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
public class SurfaceViewSign extends SurfaceView implements SurfaceHolder.Callback,Runnable {
//SurfaceHolder
private SurfaceHolder holder;
//用于绘图的Canvas
private Canvas canvas;
//子线程标志位
private boolean isDrawing;
//画笔
private Paint paint;
//路径
private Path path;
private Bitmap bitmap;
private Canvas getCanvas;
/**
* 获取mCanvas里的bitmap
* */
public Bitmap getBitmap() {
getCanvas.drawColor(Color.WHITE);//画布背景色
getCanvas.drawPath(path, paint);
getCanvas.save();
getCanvas.restore();
return bitmap;
//region bitmap压缩到文件
// File file = new File(Environment.getExternalStorageDirectory().getPath() "/share_pic.png");// 保存到sdcard根目录下，文件名为share_pic.png
// FileOutputStream fos = null;
// try {
// fos = new FileOutputStream(file);
// bitmap.compress(Bitmap.CompressFormat.PNG, 50, fos);
//
// } catch (FileNotFoundException e) {
// // TODO Auto-generated catch block
// e.printStackTrace();
// }
// try {
// fos.close();
// } catch (IOException e) {
// // TODO Auto-generated catch block
// e.printStackTrace();
// }
//endregion
}
public SurfaceViewSign(Context context) {
super(context);
initView();
}
public SurfaceViewSign(Context context, AttributeSet attrs) {
super(context, attrs);
initView();
}
public SurfaceViewSign(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
initView();
}
private void initView() {
bitmap = Bitmap.createBitmap(1000,1000, Bitmap.Config.ARGB_8888);
getCanvas = new Canvas(bitmap);
holder = getHolder();
//添加回调
holder.addCallback(this);
path =new Path();
//初始化画笔
paint =new Paint();
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(6);
paint.setAntiAlias(true);
paint.setColor(Color.RED);//画笔颜色
setFocusable(true);
setFocusableInTouchMode(true);
this.setKeepScreenOn(true);
}
//Surface的生命周期
@Override
public void surfaceCreated(SurfaceHolder holder) {
isDrawing =true;
new Thread(this).start();
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
isDrawing =false;
}
@Override
public void run() {
long start =System.currentTimeMillis();
while(isDrawing){
draw();
long end = System.currentTimeMillis();
if(end-start<100){
try{
Thread.sleep(100-end start);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
private void draw() {
try{
//锁定画布并返回画布对象
canvas = holder.lockCanvas();
canvas.drawColor(Color.WHITE);//设置画布背景色
canvas.drawPath(path, paint); //画线
}catch (Exception e){
}finally {
if(canvas !=null)
holder.unlockCanvasAndPost(canvas);//解锁
}
}
/**
* 绘制触摸滑动路径
* @param event MotionEvent
* @return true
*/
@Override
public boolean onTouchEvent(MotionEvent event) {
int x=(int) event.getX();
int y= (int) event.getY();
switch (event.getAction()){
case MotionEvent.ACTION_DOWN:
path.moveTo(x,y);
break;
case MotionEvent.ACTION_MOVE:
path.lineTo(x,y);
break;
case MotionEvent.ACTION_UP:
break;
}
return true;
}
/**
* 清屏
* @return true
*/
public boolean reDraw(){
path.reset();
return true;
}
}
然后创建一个测试Activity，然后编写他的页面代码如下：
代码语言：javascript复制<?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:focusable="true"
android:focusableInTouchMode="true"
android:orientation="vertical"
android:background="@color/white"
tools:ignore="MissingClass">
<com.kiba.test.control.surfaceview.SurfaceViewSign
android:id="@ id/sv"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1"
/>
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="@color/red"></View>
<ImageView
android:id="@ id/imageView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1"
></ImageView>
</LinearLayout>然后在activity里编写点击事件如下：
代码语言：javascript复制@SingleClick
@OnClick(R.id.imageView)
public void ImageClick()
{
Bitmap bitmap =sv.getBitmap();
imageView.setImageBitmap(bitmap);
imageView2.setImageBitmap(bitmap);
}这样就实现了简单的签名，并且获取到了签名的图片，类型是bitmap。
效果图如下：
