Android Camera 学习
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity"
android:orientation="vertical">
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="startcamera1"
android:onClick="startcamera1" />
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="startcamera2"
android:onClick="startcamera2" />
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="customcamera"
android:onClick="customcamera"/>
<ImageView
android:id="@+id/iv"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</LinearLayout>
custom.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:onClick="capture"
android:text="capture" />
<SurfaceView
android:id="@+id/preview"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
result.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Capture result"
android:gravity="center"
android:textSize="30sp"/>
<ImageView
android:id="@+id/pic"
android:scaleType="center"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</LinearLayout>
MainActivity
package com.example.myapplication;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.view.View;
import android.widget.ImageView;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
public class MainActivity extends AppCompatActivity {
private static int REQ_1=1;
private static int REQ_2=2;
private ImageView mImageView;
private String mFilepath;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mImageView=findViewById(R.id.iv);
mFilepath= Environment.getExternalStorageDirectory().getPath();
mFilepath=mFilepath+"/"+"temp.png";
}
public void startcamera1(View view){
Intent intent=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(intent,REQ_1);
}
public void startcamera2(View view){
Intent intent=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
Uri photoUri=Uri.fromFile(new File(mFilepath));
intent.putExtra(MediaStore.EXTRA_OUTPUT,photoUri);
startActivityForResult(intent,REQ_2);
}
public void customcamera(View view){
startActivity(new Intent(this,Customcamera.class));
}
@Override
protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(resultCode==RESULT_OK){
if(requestCode==REQ_1){
Bundle bundle=data.getExtras();
Bitmap bitmap= (Bitmap) bundle.get("data");
mImageView.setImageBitmap(bitmap);
}else if (requestCode==REQ_2){
FileInputStream fis = null;
try {
fis=new FileInputStream(mFilepath);
Bitmap bitmap= BitmapFactory.decodeStream(fis);
mImageView.setImageBitmap(bitmap);
} catch (FileNotFoundException e) {
e.printStackTrace();
}finally {
try {
fis.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
}
Customcamera
package com.example.myapplication;
import android.app.Activity;
import android.content.Intent;
import android.graphics.ImageFormat;
import android.hardware.Camera;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
public class Customcamera extends Activity implements SurfaceHolder.Callback {
private Camera mcamera;
private SurfaceView mpreview;
private SurfaceHolder mHolder;
private String tempfile;
private Camera.PictureCallback mPictureCallback=new Camera.PictureCallback() {
@Override
public void onPictureTaken(byte[] data, Camera camera) {
File tempfile=new File("/sdcard/temp.png");
try {
FileOutputStream fos=new FileOutputStream(tempfile);
fos.write(data);
fos.close();
Intent intent=new Intent(Customcamera.this,ResultActivity.class);
intent.putExtra("picPath",tempfile.getAbsolutePath());
startActivity(intent);
Customcamera.this.finish();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
};
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.custom);
mpreview=findViewById(R.id.preview);
mHolder=mpreview.getHolder();
mHolder.addCallback(this);
}
public void capture(View view){
Camera.Parameters parameters=mcamera.getParameters();
parameters.setPictureFormat(ImageFormat.JPEG);
parameters.setPreviewSize(800,400);
parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO);
mcamera.autoFocus(new Camera.AutoFocusCallback() {
@Override
public void onAutoFocus(boolean success, Camera camera) {
if(success){
mcamera.takePicture(null,null,mPictureCallback);
}
}
});
}
@Override
protected void onResume() {
super.onResume();
if(mcamera==null){
mcamera=getCamera();
if(mHolder!=null){
setStartPreview(mcamera,mHolder);
}
}
}
@Override
protected void onPause() {
super.onPause();
releaseCamera();
}
/**
*获取Camera对象
* */
private Camera getCamera(){
Camera camera;
try {
camera=Camera.open();
} catch (Exception e) {
camera=null;
e.printStackTrace();
}
return camera;
}
/**
* 开始预览相机内容*/
private void setStartPreview(Camera camera,SurfaceHolder holder){
try {
camera.setPreviewDisplay(holder);
//将系统camera预览角度进行调整
camera.setDisplayOrientation(90);
camera.startPreview();
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 释放相机资源*/
private void releaseCamera(){
if(mcamera!=null){
mcamera.setPreviewCallback(null);
mcamera.stopPreview();
mcamera.release();
mcamera=null;
}
}
@Override
public void surfaceCreated(@NonNull SurfaceHolder holder) {
setStartPreview(mcamera,mHolder);
}
@Override
public void surfaceChanged(@NonNull SurfaceHolder holder, int i, int i1, int i2) {
mcamera.stopPreview();
setStartPreview(mcamera,mHolder);
}
@Override
public void surfaceDestroyed(@NonNull SurfaceHolder holder) {
releaseCamera();
}
}
ResultActivity
package com.example.myapplication;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Matrix;
import android.os.Bundle;
import android.widget.ImageView;
import androidx.annotation.Nullable;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
public class ResultActivity extends Activity {
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.result);
String path=getIntent().getStringExtra("picPath");
ImageView imageView=findViewById(R.id.pic);
/** try {
FileInputStream fis=new FileInputStream(path);
Bitmap bitmap=BitmapFactory.decodeStream(fis);
Matrix matrix=new Matrix();
matrix.setRotate(90);
bitmap=Bitmap.createBitmap(bitmap,0,0,
bitmap.getWidth(),bitmap.getHeight(),matrix,true);
imageView.setImageBitmap(bitmap);
} catch (FileNotFoundException e) {
e.printStackTrace();
}*/
Bitmap bitmap= BitmapFactory.decodeFile(path);
imageView.setImageBitmap(bitmap);
}
}
Manifest文件
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.myapplication">
<uses-feature android:name="android.hardware.camera"
android:required="true" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.CAMERA"/>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/Theme.MyApplication">
<activity
android:name=".MainActivity"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".Customcamera"/>
<activity android:name=".ResultActivity"/>
</application>
</manifest>
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