Android studio 网络摄像头实现

在Android Studio中实现网络摄像头功能，你可以按照以下步骤进行操作：

1. 首先，在布局文件activity_main.xml中添加一个按钮和一个ImageView，用于调用摄像头拍照并显示照片。你可以使用以下代码：

<RelativeLayout 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">

    <Button
        android:id="@id/take_photo"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="take photo" />

    <ImageView
        android:id="@id/picture"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal" />

</RelativeLayout>

2. 接下来，在MainActivity.java文件中添加相应的代码来实现拍照和显示照片的功能。你可以使用以下代码：

import android.Manifest;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import androidx.core.content.ContextCompat;

public class MainActivity extends AppCompatActivity {

    private static final int CAMERA_PERMISSION_REQUEST_CODE = 100;
    private static final int CAMERA_REQUEST_CODE = 200;

    private Button takePhotoButton;
    private ImageView pictureImageView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        takePhotoButton = findViewById(R.id.take_photo);
        pictureImageView = findViewById(R.id.picture);

        takePhotoButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
                    ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.CAMERA}, CAMERA_PERMISSION_REQUEST_CODE);
                } else {
                    openCamera();
                }
            }
        });
    }

    private void openCamera() {
        Intent cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        startActivityForResult(cameraIntent, CAMERA_REQUEST_CODE);
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == CAMERA_REQUEST_CODE && resultCode == RESULT_OK) {
            Bitmap photo = (Bitmap) data.getExtras().get("data");
            pictureImageView.setImageBitmap(photo);
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);

        if (requestCode == CAMERA_PERMISSION_REQUEST_CODE) {
            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                openCamera();
            }
        }
    }
}

3. 最后，在AndroidManifest.xml文件中添加访问SD卡的权限。你可以使用以下代码：

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

这样，你就可以在Android Studio中实现网络摄像头功能了。当用户点击按钮时，会调用摄像头拍照，并将拍摄的照片显示在ImageView中。同时，需要确保应用已获得访问摄像头和SD卡的权限。