android实现手写签名功能

本文实例为大家分享了android手写签名展示的具体代码，供大家参考，具体内容如下

代码简单，就不发demo了，直接贴代码

package com.xx;
 
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.os.bundle;
import android.support.v7.app.appcompatactivity;
import android.view.motionevent;
import android.view.view;
import android.widget.button;
import android.widget.framelayout;
import android.widget.imageview;
import com.xx.r;
 
/**
 * description: 签名类
 * copyright:  copyright (c)2018
 * company:   
 * author:   corwin
 * version:   1.0
 * date:    2018/9/5 18:32
 * modification history:
 * date     author   version   description
 * ------------------------------------------------------------------
 * 2018/9/5  corwin   1.0     1.0 version
 */
public class signatureactivity extends appcompatactivity {
 
 private imageview imagesign;
 private signatureview mview;
 
 @override public void oncreate(bundle savedinstancestate) {
  super.oncreate(savedinstancestate);
  setcontentview(r.layout.activity_signature);
 
  imagesign = findviewbyid(r.id.iv_sign);
  framelayout framelayout = findviewbyid(r.id.fl_view);
 
  mview = new signatureview(this);
  framelayout.addview(mview);
  mview.requestfocus();
 
  button btnclear = findviewbyid(r.id.btn_clear);
  btnclear.setonclicklistener((v) -> {
    mview.clear();
  });
 
  button btnok = findviewbyid(r.id.btn_ok);
  btnok.setonclicklistener((v) -> {
    bitmap imagebitmap = mview.getcachebbitmap();
    imagesign.setimagebitmap(imagebitmap);
  });
 }
 
 /**
  * 自定义签名控件
  */
 class signatureview extends view {
 
  //画笔
  private paint paint;
 
  //画布
  private canvas cachecanvas;
 
  //位图
  private bitmap cachebbitmap;
 
  //图片保存路径
  private path path;
 
  //位图缓存
  public bitmap getcachebbitmap() {
   return cachebbitmap;
  }
 
  public signatureview(context context) {
   super(context);
   init();
  }
 
  /**
   * 初始化
   */
  private void init() {
   //设置画笔
   paint = new paint();
   paint.setantialias(true);
   paint.setstrokewidth(3);
   paint.setstyle(paint.style.stroke);
   paint.setcolor(color.black);
   path = new path();
 
   //创建位图
   cachebbitmap = bitmap.createbitmap(10, 10, bitmap.config.argb_8888);
 
   //用自定义位图构建画布
   cachecanvas = new canvas(cachebbitmap);
   //设置画布为白色
   cachecanvas.drawcolor(color.white);
  }
 
  /**
   * 清除画板，重置画笔
   */
  public void clear() {
   if (cachecanvas != null) {
    paint.setcolor(color.white);
    cachecanvas.drawpaint(paint);
    paint.setcolor(color.black);
    cachecanvas.drawcolor(color.white);
    invalidate();
   }
  }
 
  @override protected void ondraw(canvas canvas) {
   canvas.drawbitmap(cachebbitmap, 0, 0, null);
   canvas.drawpath(path, paint);
  }
 
  @override protected void onsizechanged(int w, int h, int oldw, int oldh) {
 
   int curw = cachebbitmap != null ? cachebbitmap.getwidth() : 0;
   int curh = cachebbitmap != null ? cachebbitmap.getheight() : 0;
   if (curw >= w && curh >= h) {
    return;
   }
 
   if (curw < w) curw = w;
   if (curh < h) curh = h;
   bitmap newbitmap = bitmap.createbitmap(curw, curh, bitmap.config.argb_8888);
   canvas newcanvas = new canvas();
   newcanvas.setbitmap(newbitmap);
   if (cachebbitmap != null) {
    newcanvas.drawbitmap(cachebbitmap, 0, 0, null);
   }
   cachebbitmap = newbitmap;
   cachecanvas = newcanvas;
  }
  private float cur_x, cur_y;
  @override public boolean ontouchevent(motionevent event) {
   float x = event.getx();
   float y = event.gety();
   switch (event.getaction()) {
    case motionevent.action_down: {
     cur_x = x;
     cur_y = y;
     path.moveto(cur_x, cur_y);
     break;
    }
    case motionevent.action_move: {
     path.quadto(cur_x, cur_y, x, y);
     cur_x = x;
     cur_y = y;
     break;
    }
    case motionevent.action_up: {
     cachecanvas.drawpath(path, paint);
     path.reset();
     break;
    }
   }
   invalidate();
   return true;
  }
 }
}

布局文件：

<?xml version="1.0"?>
<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:orientation="vertical"
  >
 <imageview
   android:id="@+id/iv_sign"
   android:layout_width="match_parent"
   android:layout_height="0dp"
   android:layout_gravity="center"
   android:layout_marginbottom="3dp"
   android:layout_weight="1"
   android:background="@color/white"
   />
 <framelayout
   android:id="@+id/fl_view"
   android:layout_width="match_parent"
   android:layout_height="0dp"
   android:layout_weight="1"
   android:background="@color/white"
   />
 <linearlayout
   android:layout_width="match_parent"
   android:layout_height="wrap_content"
   android:background="@android:drawable/bottom_bar"
   android:paddingtop="3dp"
   >
  <button
    android:id="@+id/btn_ok"
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    android:text="确定"
    />
  <button
    android:id="@+id/btn_clear"
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    android:text="清除"
    />
 </linearlayout>
</linearlayout>

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。