从相机捕获图像并在活动中显示 [英] Capture Image from Camera and Display in Activity

问题描述

我想编写一个模块，单击按钮即可打开相机，我可以单击并捕获图像.如果我不喜欢该图像，我可以将其删除，然后再单击一张图像，然后选择该图像，它应该返回并在活动中显示该图像.

I want to write a module where on a click of a button the camera opens and I can click and capture an image. If I don't like the image I can delete it and click one more image and then select the image and it should return back and display that image in the activity.

推荐答案

这是一个示例 Activity，它将启动相机应用程序，然后检索图像并显示它.

Here's an example activity that will launch the camera app and then retrieve the image and display it.

package edu.gvsu.cis.masl.camerademo;

import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;

public class MyCameraActivity extends Activity
{
    private static final int CAMERA_REQUEST = 1888; 
    private ImageView imageView;
    private static final int MY_CAMERA_PERMISSION_CODE = 100;

    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        this.imageView = (ImageView)this.findViewById(R.id.imageView1);
        Button photoButton = (Button) this.findViewById(R.id.button1);
        photoButton.setOnClickListener(new View.OnClickListener()
        {
            @Override
            public void onClick(View v)
            {
                if (checkSelfPermission(Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED)
                {
                    requestPermissions(new String[]{Manifest.permission.CAMERA}, MY_CAMERA_PERMISSION_CODE);
                }
                else
                {
                    Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE); 
                    startActivityForResult(cameraIntent, CAMERA_REQUEST);
                } 
            }
        });
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults)
    {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (requestCode == MY_CAMERA_PERMISSION_CODE)
        {
            if (grantResults[0] == PackageManager.PERMISSION_GRANTED)
            {
                Toast.makeText(this, "camera permission granted", Toast.LENGTH_LONG).show();
                Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE); 
                startActivityForResult(cameraIntent, CAMERA_REQUEST);
            }
            else
            {
                Toast.makeText(this, "camera permission denied", Toast.LENGTH_LONG).show();
            }
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data)
    {  
        if (requestCode == CAMERA_REQUEST && resultCode == Activity.RESULT_OK)
        {  
            Bitmap photo = (Bitmap) data.getExtras().get("data"); 
            imageView.setImageBitmap(photo);
        }  
    } 
}

请注意，相机应用本身让您能够查看/重新拍摄图像，一旦图像被接受，活动就会显示它.

Note that the camera app itself gives you the ability to review/retake the image, and once an image is accepted, the activity displays it.

这是上述活动使用的布局.它只是一个 LinearLayout，包含一个 ID 为 button1 的 Button 和一个 ID 为 imageview1 的 ImageView:

Here is the layout that the above activity uses. It is simply a LinearLayout containing a Button with id button1 and an ImageView with id imageview1:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
    <Button android:id="@+id/button1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/photo"></Button>
    <ImageView android:id="@+id/imageView1" android:layout_height="wrap_content" android:src="@drawable/icon" android:layout_width="wrap_content"></ImageView>

</LinearLayout>

最后一个细节，一定要补充:

And one final detail, be sure to add:

<uses-feature android:name="android.hardware.camera"></uses-feature> 

如果相机对于您的应用功能来说是可选的.确保在权限中将 require 设置为 false.像这样

and if camera is optional to your app functionality. make sure to set require to false in the permission. like this

<uses-feature android:name="android.hardware.camera" android:required="false"></uses-feature>

到您的 manifest.xml.

to your manifest.xml.

这篇关于从相机捕获图像并在活动中显示的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！