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本文实例为大家分享了android自定义camera拍照并查看图片的具体代码，供大家参考，具体内容如下
1、打开相机
a.预览拍摄图片，需用到surfaceview，并且实现其回调函数implements surfaceholder.callback；
activity_camera.xml
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<?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" >
<surfaceview
android:id="@+id/sv"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1" />
<button
android:id="@+id/btn_camera"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="拍照" />
</linearlayout>
2、获取相机并开启预览
/**
* 获取系统相机
*
* @return
*/
private camera getccamera() {
camera camera = null;
try {
camera = camera.open();
} catch (exception e) {
camera = null;
}
return camera;
}
/**
* 显示相机预览图片
*
* @return
*/
private void showcameraview(camera camera,surfaceholder holder)
{
try {
camera.setpreviewdisplay(holder);
camera.setdisplayorientation(90);
camera.startpreview();
}catch (exception e){
e.printstacktrace();
};
}
/**
** 实现界面回调处理
*/
@override
public void surfacecreated(surfaceholder holder) {
showcameraview(mcamera, holder);
}
@override
public void surfacechanged(surfaceholder holder, int format, int width, int height) {
mcamera.stoppreview();
showcameraview(mcamera, holder);
}
@override
public void surfacedestroyed(surfaceholder holder) {
clearcamera();
}
}
3、相机主页面处理
public class cameraactivity extends appcompatactivity implements surfaceholder.callback{
private surfaceview sv;
private camera mcamera;
private surfaceholder holder;
@override
protected void oncreate(bundle savedinstancestate) {
super.oncreate(savedinstancestate);
setcontentview(r.layout.activity_camera);
sv = (surfaceview)findviewbyid(r.id.sv);
holder = sv.getholder();
holder.addcallback(this);
findviewbyid(r.id.btn_camera).setonclicklistener(new view.onclicklistener() {
@override
public void onclick(view v) {
// 获取当前相机参数
camera.parameters parameters = mcamera.getparameters();
// 设置相片格式
parameters.setpictureformat(imageformat.jpeg);
// 设置预览大小
parameters.setpreviewsize(800, 480);
// 设置对焦方式，这里设置自动对焦
parameters.setfocusmode(camera.parameters.focus_mode_auto);
mcamera.autofocus(new camera.autofocuscallback() {
@override
public void onautofocus(boolean success, camera camera) {
// 判断是否对焦成功
if (success) {
// 拍照 第三个参数为拍照回调
mcamera.takepicture(null, null, new camera.picturecallback() {
@override
public void onpicturetaken(byte[] data, camera camera) {
// data为完整数据
file file = new file("/sdcard/photo.png");
// 使用流进行读写
try {
fileoutputstream fos = new fileoutputstream(file);
try {
fos.write(data);
// 关闭流
fos.close();
// 查看图片
intent intent = new intent();
// 传递路径
intent.putextra("path", file.getabsolutepath());
setresult(0,intent);
finish();
} catch (ioexception e) {
// todo auto-generated catch block
e.printstacktrace();
}
} catch (filenotfoundexception e) {
// todo auto-generated catch block
e.printstacktrace();
}
}
});
}
}
});
}
});
}
@override
protected void onresume() {
super.onresume();
if (mcamera == null) {
mcamera = getcamera();
if (holder != null) {
showcameraview(mcamera, holder);
}
}
}
@override
protected void onpause() {
// todo auto-generated method stub
super.onpause();
// activity暂停时我们释放相机内存
clearcamera();
}
@override
protected void ondestroy() {
super.ondestroy();
}
/**
* 释放相机的内存
*/
private void clearcamera() {
// 释放hold资源
if (mcamera != null) {
// 停止预览
mcamera.stoppreview();
mcamera.setpreviewcallback(null);
// 释放相机资源
mcamera.release();
mcamera = null;
}
}
4、启动activity（设置拍照完图片路径返回显示图片处理，一定要对图片进行采样率操作（很可能拍照的图片太多而无法显示，又不报任何异常））
public class mainactivity extends appcompatactivity {
private imageview cameraiv;
@override
protected void onactivityresult(int requestcode, int resultcode, intent data) {
if(resultcode == 0 && requestcode == 100)
{
string path = data.getstringextra("path");
bitmapfactory.options options = new bitmapfactory.options();
options.injustdecodebounds = true;
bitmapfactory.decodefile(path, options);
imagesize imagesize = getimageviewsize(cameraiv);
options.insamplesize = caculateinsamplesize(options,
imagesize.width, imagesize.height);
// 使用获得到的insamplesize再次解析图片
options.injustdecodebounds = false;
bitmap bitmap = bitmapfactory.decodefile(path, options);
cameraiv.setimagebitmap(bitmap);
}
super.onactivityresult(requestcode, resultcode, data);
}
@override
protected void oncreate(bundle savedinstancestate) {
super.oncreate(savedinstancestate);
setcontentview(r.layout.activity_main);
button openbutton = (button) findviewbyid(r.id.button);
cameraiv = (imageview) findviewbyid(r.id.imageview);
openbutton.setonclicklistener(new view.onclicklistener() {
@override
public void onclick(view v) {
intent intent = new intent(mainactivity.this,cameraactivity.class);
startactivityforresult(intent,100);
}
});
}
/* 根据需求的宽和高以及图片实际的宽和高计算samplesize
*
* @param options
* @param width
* @param height
* @return
*/
public static int caculateinsamplesize(bitmapfactory.options options, int reqwidth,
int reqheight)
{
int width = options.outwidth;
int height = options.outheight;
int insamplesize = 1;
if (width > reqwidth || height > reqheight)
{
int widthradio = math.round(width * 1.0f / reqwidth);
int heightradio = math.round(height * 1.0f / reqheight);
insamplesize = math.max(widthradio, heightradio);
}
return insamplesize;
}
public static imagesize getimageviewsize(imageview imageview)
{
imagesize imagesize = new imagesize();
displaymetrics displaymetrics = imageview.getcontext().getresources()
.getdisplaymetrics();
linearlayout.layoutparams lp = (linearlayout.layoutparams)imageview.getlayoutparams();
int width = imageview.getwidth();// 获取imageview的实际宽度
if (width <= 0)
{
width = lp.width;// 获取imageview在layout中声明的宽度
}
if (width <= 0)
{
width = displaymetrics.widthpixels;
}
int height = imageview.getheight();// 获取imageview的实际高度
if (height <= 0)
{
height = lp.height;// 获取imageview在layout中声明的宽度
}
if (height <= 0)
{
height = displaymetrics.heightpixels;
}
imagesize.width = width;
imagesize.height = height;
return imagesize;
}
public static class imagesize
{
int width;
int height;
}
}
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