Android realizes flashlight function through LED

This example shares the specific code for Android to realize the flashlight function through LED for your reference. The specific contents are as follows

Step 1: add permissions:

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

Step 2 realize flashlight tools:

import android.hardware.Camera;
import android.hardware.Camera.Parameters;
import android.os.AsyncTask;

/**
 *Caution: On some devices,this method may take a long time to complete. It is best
 *to call this method from a worker thread (possibly using android.os.AsyncTask) to
 *avoid blocking the main application UI thread.
 */

public class FlashlightUtil extends AsyncTask<String,String,String> {

 private Camera camera;
 private int cameraId = 0; // 此功能目前不实用，这里不做实现 ， 但不能删除
 private Parameters parameters;
 public boolean isTorch = false;
 private boolean canFinish = false;
 private static FlashlightUtil flashlightUtil;

 private FlashlightUtil() {

 }

 /**
  * 设置手电筒开关，打开或关闭手电筒，根据手电筒的状态来设置相反的状态 void 2016年1月12日
  */
 public static void setSwitch() {
  if (null == flashlightUtil) {
   flashlightUtil = new FlashlightUtil();
   flashlightUtil.execute("");
  }
  flashlightUtil.setONOFF();
 }

 @Override
 protected String doInBackground(String... params) {
  // TODO Auto-generated method stub

  while (!canFinish) {
   if (null == camera) {
    camera = Camera.open(cameraId);
   }
   parameters = camera.getParameters();
   if (isTorch) {
    if (parameters.getFlashMode().equals(Parameters.FLASH_MODE_OFF)) {
     // 打开镁光灯
     parameters.setFlashMode(Parameters.FLASH_MODE_TORCH);
     camera.setParameters(parameters);
     camera.startPreview();
    }
   } else {
    if (parameters.getFlashMode().equals(
      Parameters.FLASH_MODE_TORCH)) {
     // 关闭镁光灯
     camera.stopPreview(); // 关掉亮灯
     camera.release(); // 关掉照相机
     camera = null;
    }
   }
  }

  return null;
 }

 /**
  * 此功能暂时关闭
  * @hide
  */
 public FlashlightUtil setCameraId(int cameraId) {
  this.cameraId = cameraId;
  return flashlightUtil;
 }

 /**
  * 打开关闭手电筒，默认第一次为打开 2016年1月12日
  */
 private void setONOFF() {
  isTorch = !isTorch;
 }

}

Step 3: add the trigger event of flashlight button (this is implemented through onclick in the layout file)

/**
 * 打开手电筒
 */
public void openFlashlight(View view) {
 FlashlightUtil.setSwitch() ;
}

The function of flashlight is relatively simple. Here, one-step opening and closing is realized.

The above is the whole content of this article. I hope it will help you in your study, and I hope you will support us a lot.