用c语言怎么实现android手机调用摄像头

用c语言怎么实现android手机调用摄像头

android 中实现网页调用摄像头功能方法·如下：
1/apk/res/android"
xmlns:tools="schemas/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".CameraWebviewActivity" >

android:id="@+id/bt"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Camera"
android:layout_alignParentTop="true"
/>

android:id="@+id/wv"
android:layout_width="fill_parent"
android:layout_height="match_parent"
android:layout_below="@+id/bt"
/>


4.、编写activity：
public class CameraWebviewActivity extends Activity {

private final static String TAG = "CameraWebviewActivity";

private Button bt;
private WebView wv;
public String fileFullName;//照相后的照片的全整路径
private boolean fromTakePhoto; //是否是从摄像界面返回的webview

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_camera_webview);
initViews();
}

private void initViews() {

bt = (Button) findViewById(R.id.bt);
bt.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
System.out.println("----------------");
takePhoto( Math.random()*1000+1 + ".jpg");
}
});

wv = (WebView) findViewById(R.id.wv);
WebSettings setting = wv.getSettings();
setting.setJavaScriptEnabled(true);
wv.setWebViewClient(new WebViewClient(){
@Override
public void onPageStarted(WebView view, String url, Bitmap favicon) {
super.onPageStarted(view, url, favicon);
}

@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
return super.shouldOverrideUrlLoading(view, url);
}

@Override
public void onPageFinished(WebView view, String url) {
super.onPageFinished(view, url);
}

});

wv.setWebChromeClient(new WebChromeClient(){
@Override//实现js中的alert弹窗在Activity中显示
public boolean onJsAlert(WebView view, String url, String message, JsResult result) {
Log.d(TAG, message);
result.confirm();
return true;
}
});

wv.loadUrl("file:///android_asset/index.html");
final Handler mHandler = new Handler();
//webview增加javascript接口，监听html页面中的js点击事件
wv.addJavascriptInterface(new Object(){
public String clickOnAndroid() {//将被js调用
mHandler.post(new Runnable() {
public void run() {
fromTakePhoto = true;
//调用 启用摄像头的自定义方法
takePhoto("testimg" + Math.random()*1000+1 + ".jpg");
System.out.println("========fileFullName: " + fileFullName);

}
});
return fileFullName;
}
}, "demo");
}


public void takePhoto(String filename) {
System.out.println("----start to take photo2 ----");
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
intent.putExtra(MediaStore.EXTRA_MEDIA_TITLE, "TakePhoto");

//判断是否有SD卡
String sdDir = null;
boolean isSDcardExist = Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED);
if(isSDcardExist) {
sdDir = Environment.getExternalStorageDirectory().getAbsolutePath();
} else {
sdDir = Environment.getRootDirectory().getAbsolutePath();
}
//确定相片保存路径
String targetDir = sdDir + "/" + "webview_camera";
File file = new File(targetDir);
if (!file.exists()) {
file.mkdirs();
}
fileFullName = targetDir + "/" + filename;
System.out.println("----taking photo fileFullName: " + fileFullName);
//初始化并调用摄像头
intent.putExtra(MediaStore.Images.Media.MIME_TYPE, "image/jpeg");
intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(new File(fileFullName)));
startActivityForResult(intent, 1);
}


@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
System.out.println("----requestCode: " + requestCode + "; resultCode " + resultCode + "; fileFullName: " + fileFullName);
if (fromTakePhoto && requestCode ==1 && resultCode ==-1) {
wv.loadUrl("javascript:wave2('" + fileFullName + "')");
} else {
wv.loadUrl("javascript:wave2('Please take your photo')");
}
fromTakePhoto = false;
super.onActivityResult(requestCode, resultCode, data);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.camera_webview, menu);
return true;
}

}

虽然我很聪明，但这么说真的难到我了