Android 照相机的实例应用

android 照相机的实例应用

关键技术：

surfaceholder.callback

public class mycamerademo extends activity { 
  private surfaceview surface = null ; 
  private button but = null ; 
  private surfaceholder holder = null ; 
  private camera cam = null ; 
  private boolean previewrunning = true ; 
  @override 
  public void oncreate(bundle savedinstancestate) { 
    super.oncreate(savedinstancestate); 
    super.setcontentview(r.layout.main); 
    this.but = (button) super.findviewbyid(r.id.but) ; 
    this.surface = (surfaceview) super.findviewbyid(r.id.surface) ; 
     
    this.holder = this.surface.getholder() ; 
    this.holder.addcallback(new mysurfaceviewcallback()) ; 
    //设置缓冲类型 
    this.holder.settype(surfaceholder.surface_type_push_buffers) ; 
    //设置分辨率 
    this.holder.setfixedsize(600, 350); 
     
    this.but.setonclicklistener(new onclicklistenerimpl()) ; 
  } 
  private class onclicklistenerimpl implements onclicklistener { 
 
    @override 
    public void onclick(view v) { 
      if(mycamerademo.this.cam != null) { 
        //自动对焦 
        mycamerademo.this.cam.autofocus(new autofocuscallbackimpl()) ; 
      } 
    } 
     
  } 
   
  private class mysurfaceviewcallback implements surfaceholder.callback { 
 
    //当预览界面格式大小改变时，调用 
    public void surfacechanged(surfaceholder holder, int format, int width, 
        int height) { 
       
    } 
 
    //初次实例化界面调用 
    public void surfacecreated(surfaceholder holder) { 
      mycamerademo.this.cam = camera.open(0) ;  // 取得第一个摄像头 
      //窗口服务 
      windowmanager manager = (windowmanager) mycamerademo.this 
          .getsystemservice(context.window_service); 
      //取得display显示对象 
      display display = manager.getdefaultdisplay() ; 
      //照相机参数 
      parameters param = mycamerademo.this.cam.getparameters() ; 
      //将照相机预览大小设置为display大小 
      param.setpreviewsize(display.getwidth(), display.getheight()) ; 
      param.setpreviewframerate(5) ; // 一秒5帧 
      param.setpictureformat(pixelformat.jpeg) ; // 图片形式 
      param.set("jpen-quality", 80) ;//图片质量，最高100 
      mycamerademo.this.cam.setparameters(param) ; 
      try { 
        mycamerademo.this.cam.setpreviewdisplay(mycamerademo.this.holder) ; 
      } catch (ioexception e) { 
      } 
      mycamerademo.this.cam.startpreview() ; // 进行预览 
      mycamerademo.this.previewrunning = true ;  // 已经开始预览 
    } 
 
    @override 
    public void surfacedestroyed(surfaceholder holder) { 
      if(mycamerademo.this.cam != null) { 
        if(mycamerademo.this.previewrunning) { 
          mycamerademo.this.cam.stoppreview() ;  // 停止预览 
          mycamerademo.this.previewrunning = false ; 
        } 
        mycamerademo.this.cam.release() ; 
      } 
    } 
     
  } 
   
  private class autofocuscallbackimpl implements autofocuscallback { 
 
    @override 
    public void onautofocus(boolean success, camera camera) { 
      if(success) {  // 成功 
        mycamerademo.this.cam.takepicture(sc, pc, jpgcall) ; 
      } 
    } 
     
  } 
   
  private picturecallback jpgcall = new picturecallback() { 
 
    @override 
    public void onpicturetaken(byte[] data, camera camera) {  // 保存图片的操作 
      bitmap bmp = bitmapfactory.decodebytearray(data, 0, data.length); 
      string filename = environment.getexternalstoragedirectory() 
          .tostring() 
          + file.separator 
          + "mldnphoto" 
          + file.separator 
          + "mldn_" + system.currenttimemillis() + ".jpg"; 
      file file = new file(filename) ; 
      if (!file.getparentfile().exists()) { 
        file.getparentfile().mkdirs() ; // 创建文件夹 
      } 
      try { 
        bufferedoutputstream bos = new bufferedoutputstream(new fileoutputstream(file)) ; 
        bmp.compress(bitmap.compressformat.jpeg, 80, bos) ; // 向缓冲区之中压缩图片 
        bos.flush() ; 
        bos.close() ; 
        toast.maketext(mycamerademo.this, 
            "拍照成功，照片已保存在" + filename + "文件之中！", toast.length_short) 
            .show(); 
      } catch (exception e) { 
        toast.maketext(mycamerademo.this, 
            "拍照失败！", toast.length_short) 
            .show(); 
      } 
      mycamerademo.this.cam.stoppreview() ; 
      mycamerademo.this.cam.startpreview() ; 
    } 
     
  } ; 
   
  private shuttercallback sc = new shuttercallback(){ 
    @override 
    public void onshutter() { 
      // 按下快门之后进行的操作 
    } 
  } ; 
  private picturecallback pc = new picturecallback() { 
 
    @override 
    public void onpicturetaken(byte[] data, camera camera) { 
       
    } 
     
  } ; 
} 

 主布局函数

<?xml version="1.0" encoding="utf-8"?> 
<linearlayout  
  xmlns:android="http://schemas.android.com/apk/res/android" 
  android:orientation="vertical"  
  android:layout_width="fill_parent" 
  android:layout_height="fill_parent"> 
  <button 
    android:id="@+id/but"  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content"  
    android:text="照相" /> 
  <surfaceview 
    android:id="@+id/surface" 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent" />  
</linearlayout> 

以上就是android 相机的使用方法，如有疑问请留言或者到本站社区交流讨论，感谢阅读，希望能帮助到大家，谢谢大家对本站的支持！