【发布时间】：2018-01-11 03:52:12
【问题描述】：
我设法在棒棒糖设备上运行，在清单上添加了权限，但对于 marshamellow，它没有解决用于 jst 冻结 n 的应用程序在尝试打开 flash 时什么也不做
import android.Manifest;
import android.app.Activity;
import android.content.Context;
import android.os.Build;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.content.pm.PackageManager;
import android.hardware.Camera;
import android.hardware.Camera.Parameters;
import android.view.View;
import android.widget.Button;
import android.widget.ImageButton;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
Button button;
private Camera camera;
private boolean isFlashOn;
private boolean hasFlash;
Parameters params;
private Context mContext = MainActivity.this;
private static final int REQUEST = 112;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final ImageButton imgbutton = (ImageButton)findViewById(R.id.imageButton);
hasFlash = getApplicationContext().getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH);
checkPermission();
//getCamera();
imgbutton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (isFlashOn) {
turnOffFlash();
Toast.makeText(MainActivity.this, "Flash OFF!", Toast.LENGTH_SHORT).show();
imgbutton.setImageResource(R.drawable.light_off);
} else {
turnOnFlash();
Toast.makeText(MainActivity.this, "Flash ON!", Toast.LENGTH_SHORT).show();
imgbutton.setImageResource(R.drawable.light_on);
}
}
});
}
public void checkPermission() {
if (Build.VERSION.SDK_INT >= 23) {
String[] PERMISSIONS = {android.Manifest.permission.CAMERA};
if (!hasPermissions(mContext, PERMISSIONS)) {
ActivityCompat.requestPermissions((Activity) mContext, PERMISSIONS, REQUEST);
} else {
getCamera() ;
}
} else {
getCamera() ;
}
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
switch (requestCode) {
case REQUEST: {
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
getCamera() ;
} else {
Toast.makeText(mContext, "The app was not allowed to access camera", Toast.LENGTH_LONG).show();
}
}
}
}
private static boolean hasPermissions(Context context, String... permissions) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && context != null && permissions != null) {
for (String permission : permissions) {
if (ActivityCompat.checkSelfPermission(context, permission) != PackageManager.PERMISSION_GRANTED) {
return false;
}
}
}
return true;
}
private void getCamera() {
if (camera == null) {
try {
camera = Camera.open();
params = camera.getParameters();
}catch (Exception e) {
}
}
}
private void turnOnFlash() {
if(!isFlashOn) {
if(camera == null || params == null) {
return;
}
params = camera.getParameters();
params.setFlashMode(Parameters.FLASH_MODE_TORCH);
camera.setParameters(params);
camera.startPreview();
isFlashOn = true;
}
}
private void turnOffFlash() {
if (isFlashOn) {
if (camera == null || params == null) {
return;
}
params = camera.getParameters();
params.setFlashMode(Parameters.FLASH_MODE_OFF);
camera.setParameters(params);
camera.stopPreview();
isFlashOn = false;
}
}
@Override
protected void onDestroy(){
super.onDestroy();
if(camera!=null){
camera.stopPreview();
camera.setPreviewCallback(null);
camera.release();
camera = null;
}
}
protected void onStop() {
super.onStop();
}
@Override
protected void onResume() {
super.onResume();
if(hasFlash)
turnOnFlash();
}
@Override
protected void onPause() {
super.onPause();
}
}
更新：最后我设法获得了 marshamello 设备的大许可.. 需要以编程方式在 marshamello n 上获得许可，所以这就是我通过这个社区解决的问题，谢谢
【问题讨论】：
-
您还需要添加此权限。
标签： android permissions flashlight