android – 谷歌Nexus 5上的Flash Torch

在阅读了其他用户的所有帖子并遇到同样的问题后,我能够创建一个简单的工作应用程序来打开我的Nexus 5上的闪光灯,这是“OnCreate()”方法：

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    Camera mCamera;
    SurfaceView preview;
    mCamera = Camera.open();
    Parameters params = mCamera.getParameters();
    params.setFlashMode(Parameters.FLASH_MODE_TORCH);
    mCamera.setParameters(params);  
    mCamera.startPreview();
    try {
        mCamera.setPreviewTexture(new SurfaceTexture(0));
        } catch (IOException e) {
        e.printStackTrace();
        }

    if (savedInstanceState == null) {
        getSupportFragmentManager().beginTransaction()
                .add(R.id.container, new PlaceholderFragment()).commit();
    }
}

在清单中我添加了这些权限：

<uses-permission android:name="android.permission.CAMERA"/>
<uses-permission android:name="android.permission.FLASHLIGHT" />
<uses-feature android:name="android.hardware.camera" android:required="false" />
<uses-feature android:name="android.hardware.camera.autofocus" android:required="false" />
<uses-feature android:name="android.hardware.camera.flash" android:required="false" />

我需要把它放在一个更复杂的应用程序中,它也使用相机.如何将其添加为方法/类或其他内容以使其无冲突地工作？

谢谢

解决方法:

完成编辑：

根据您的意见,我了解您希望在使用相机时使用手电筒闪光模式.这是可能的,下面是一些纯粹的概念验证代码.请注意,它实现了非常小的异常处理,并且需要进行一些调整才能满足您的需要,但它将展示入门的基础知识.

main.xml中

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:gravity="center"
    android:orientation="vertical" >

    <android.view.SurfaceView android:id="@+id/surfaceView"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal" >

        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:onClick="initialize"
            android:text="Init" />

        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:onClick="takePicture"
            android:text="Picture" />

        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:onClick="release"
            android:text="Done" />

        <ToggleButton android:id="@+id/tgbToggle"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1" />

    </LinearLayout>

</LinearLayout>

MainActivity.java

public class MainActivity extends Activity
{
    Camera camera;
    Parameters params;
    SurfaceView surfaceView;
    SurfaceHolder surfaceHolder;
    PictureCallback callBackJpeg;

    Button start, stop, capture;
    ToggleButton toggle;

    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        toggle = (ToggleButton) findViewById(R.id.tgbToggle);
        toggle.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
                @Override
                public void onCheckedChanged(CompoundButton button, boolean checked)
                {
                    toggleTorch(checked);
                }           
            }
        );

        surfaceView = (SurfaceView)findViewById(R.id.surfaceView);
        surfaceHolder = surfaceView.getHolder();
        surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

        callBackJpeg = new PictureCallback() {
            public void onPictureTaken(byte[] data, Camera camera)
            {
                FileOutputStream fos = null;
                String filename = String.format(Environment.getExternalStorageDirectory().toString() +
                                                "/%d.jpg", System.currentTimeMillis());
                try
                {
                    fos = new FileOutputStream(filename);
                    fos.write(data);
                    fos.close();

                    Toast.makeText(MainActivity.this, "Picture saved - " + filename, 0).show();
                }
                catch (FileNotFoundException e)
                {
                    e.printStackTrace();
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                }
            }
        };
    }

    public void initialize(View v)
    {
        camera = Camera.open();
        params = camera.getParameters();
        try
        {
            camera.setPreviewDisplay(surfaceHolder);
        }
        catch (IOException e)
        {
            Toast.makeText(this, "Unable to set preview display.", 0).show();
            return;
        }       
        camera.startPreview();
    }

    public void takePicture(View v)
    {
        camera.takePicture(null, null, callBackJpeg);
    }

    public void release(View v)
    {
        camera.stopPreview();
        camera.release();
    }

    private void toggleTorch(boolean turnOn)
    {
        params.setFlashMode(turnOn ? Parameters.FLASH_MODE_TORCH : Parameters.FLASH_MODE_OFF);
        camera.setParameters(params);
        camera.startPreview();
    }
}

当应用程序启动时,您需要单击Init以启动相机预览.在此之后,您可以使用切换按钮打开和关闭Torch,然后单击Picture以拍摄将保存到外部存储目录根目录的图片.在退出或最小化应用程序之前,您应该单击“完成”.

编辑：最小

将以下权限添加到清单：

<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.FLASHLIGHT" />

将以下内容添加到您的活动中：

Camera camera;
Parameters params;

@Override
public void onResume()
{
    super.onResume();
    camera = Camera.open();
    params = camera.getParameters();
    params.setFlashMode(Parameters.FLASH_MODE_TORCH);
    camera.setParameters(params);
    camera.startPreview();
}

@Override
public void onPause()
{
    super.onPause();
    camera.release();
}

标签：android,camera,flashlight,nexus-5
来源： https://codeday.me/bug/20190629/1322456.html