如果你只想制作一个简单的手电筒应用程序,你应该编辑你的问题。
将相机与新的android.hardware配合使用。camera 2更复杂。
我曾尝试使用android studio和nexus lg 5x制作相机预览应用程序,但没有成功。
相反,如果你只是想打开闪光灯,下面是代码:
void torch(){
/* turn on the flash light */
CameraManager cameraManager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);
try {
String[] cameraID = new String[]{};
cameraID = cameraManager.getCameraIdList();
for(int i = 0; i<cameraID.length; i++){
Log.e(TAG,cameraID[i]);
}
/* camera id is 0 and 1. 0 is the back camera, 1 is the front camera */
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
cameraManager.setTorchMode(cameraID[0],true);
//true means turned on, false, means turned off.
}
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
显示:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.test">
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-feature android:name="android.hardware.camera" />
<uses-feature android:name="android.hardware.camera.autofocus" />
<uses-feature android:name="android.hardware.camera2.full" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/MaterialTheme">
<activity
android:name=".MainActivity"
android:screenOrientation="portrait"
android:label="@string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
主要活动.java:
package com.example.test;
import android.app.Activity;
import android.graphics.Camera;
import android.hardware.camera2.params.InputConfiguration;
import android.os.Build;
import android.os.Bundle;
public class MainActivity extends Activity {
private final static String TAG = "Camera2testJ";
private Size mPreviewSize;
private TextureView mTextureView;
private CameraDevice mCameraDevice;
private CaptureRequest.Builder mPreviewBuilder;
private CameraCaptureSession mPreviewSession;
private Button mBtnShot;
private static final SparseIntArray ORIENTATIONS = new SparseIntArray();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_main);
mTextureView = (TextureView)findViewById(R.id.texture);
mTextureView.setSurfaceTextureListener(mSurfaceTextureListener);
mBtnShot = (Button)findViewById(R.id.btn_takepicture);
mBtnShot.setOnClickListener(new OnClickListener(){
@Override
public void onClick(View v) {
Log.e(TAG, "mBtnShot clicked");
torch();
}
});
}
void torch(){
/* try the flash light */
CameraManager cameraManager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);;
try {
String[] cameraID = new String[]{};
cameraID = cameraManager.getCameraIdList();
for(int i = 0; i<cameraID.length; i++){
Log.e(TAG,cameraID[i]);
}
/* camera id is 0 and 1. which one is the front or the back camera? */
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
cameraManager.setTorchMode(cameraID[0],true);
}
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
布局activity_main.xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<TextureView
android:id="@+id/texture"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true" />
<Button
android:id="@+id/btn_takepicture"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:text="@string/picture"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true" />
</RelativeLayout>
