Question

我正在开发一个应用程序，在我点击按钮一次后每4秒自动开始捕获图像..但是我收到错误..这就是我在做什么

buttonClick.setOnClickListener(new OnClickListener() {
        public void onClick(View v) {
             new Thread(new Runnable() {
                    public void run() {

                        while(true)
                        {
                        preview.camera.takePicture(shutterCallback, rawCallback,
                                jpegCallback);
                        try {
                            Thread.sleep(4000);
                        } catch (InterruptedException e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        }
                        }
                        }
                }).start();

    }
    });

上面的代码给出了错误..但是当我这样做时

buttonClick.setOnClickListener(new OnClickListener() {
        public void onClick(View v) {
                  preview.camera.takePicture(shutterCallback,jpegCallback);
}       
});

它工作正常！

这是错误日志

`01-07 23:53:16.892: W/dalvikvm(1625): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
01-07 23:53:16.912: E/AndroidRuntime(1625): FATAL EXCEPTION: main
01-07 23:53:16.912: E/AndroidRuntime(1625): java.lang.RuntimeException: Fail to connect to camera service
01-07 23:53:16.912: E/AndroidRuntime(1625):     at android.hardware.Camera.native_setup(Native Method)
01-07 23:53:16.912: E/AndroidRuntime(1625):     at android.hardware.Camera.<init>(Camera.java:110)
01-07 23:53:16.912: E/AndroidRuntime(1625):     at android.hardware.Camera.open(Camera.java:90)
01-07 23:53:16.912: E/AndroidRuntime(1625):     at com.android.mycamera.Preview.surfaceCreated(Preview.java:35)
01-07 23:53:16.912: E/AndroidRuntime(1625):     at android.view.SurfaceView.updateWindow(SurfaceView.java:532)
01-07 23:53:16.912: E/AndroidRuntime(1625):     at android.view.SurfaceView.dispatchDraw(SurfaceView.java:339)
01-07 23:53:16.912: E/AndroidRuntime(1625):     at android.view.ViewGroup.drawChild(ViewGroup.java:1638)
`

任何帮助都将受到高度赞赏！

Answer 1

这可能是因为它必须在UI线程上，试试这个：

buttonClick.setOnClickListener(new OnClickListener() {
    public void onClick(View v) {
        final Handler h = new Handler():
        h.post(new Runnable() {
                public void run() {
                    preview.camera.takePicture(shutterCallback, rawCallback,
                            jpegCallback);
                    h.postDelayed(this, 4000);
                    }
            });

}
});

这将在UI线程上每4秒执行相同的代码。不要忘记放置某种类型的标志，以阻止它在您的活动暂停时执行。

Android：每4秒自动捕获一次图像

1 个答案: