Android 之 打开相机 打开相册

Android 之 打开系统摄像头拍照 打开系统相册，并展示

1，清单文件 AndroidManifest.xml

```

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

<!--文件读取权限-->

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

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

<!--相机权限-->

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

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

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

<application ...>

...

<provider

android:name="androidx.core.content.FileProvider"

android:authorities="com.example.camera.fileprovider"

android:grantUriPermissions="true">

<meta-data

android:name="android.support.FILE_PROVIDER_PATHS"

android:resource="@xml/my_image" />

</provider>

</application>

```

2，配置文件 my_image.xml

```

<?xml version="1.0" encoding="utf-8"?>

<paths xmlns:android="" target="_blank">http://schemas.android.com/apk/res/android">

<external-path

name="my_image"

path="/" />

</paths>

```

3，布局

<?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"

android:orientation="vertical"

tools:context="com.sjl.nfc.MainActivity">

<ImageView

android:id="@+id/main_img01"

android:layout_width="200dp"

android:layout_height="200dp"

android:layout_gravity="center_horizontal"

android:src="@drawable/img_mine06" />

<Button

android:id="@+id/main_btn01"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center_horizontal"

android:text="打开相机" />

<Button

android:id="@+id/main_btn02"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center_horizontal"

android:text="打开相册" />

</LinearLayout>

4，主要代码 java

package com.sjl.nfc;

import android.annotation.TargetApi;

import android.app.Activity;

import android.content.ContentUris;

import android.content.Intent;

import android.database.Cursor;

import android.graphics.Bitmap;

import android.graphics.BitmapFactory;

import android.graphics.drawable.BitmapDrawable;

import android.net.Uri;

import android.os.Bundle;

import android.provider.DocumentsContract;

import android.provider.MediaStore;

import android.util.Base64;

import android.util.Log;

import android.widget.Button;

import android.widget.ImageView;

import android.widget.Toast;

import androidx.annotation.Nullable;

import androidx.appcompat.app.AppCompatActivity;

import androidx.core.content.FileProvider;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.FileNotFoundException;

import java.io.IOException;

/**

* 项目模板

*/

public class MainActivity extends AppCompatActivity {

private static final String TAG = "MainActivity";

private ImageView main_img01;

private Uri imageUri;

@Override

protected void onCreate(@Nullable Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main_activity);

main_img01 = findViewById(R.id.main_img01);

Button main_btn01 = findViewById(R.id.main_btn01); // 打开相机

Button main_btn02 = findViewById(R.id.main_btn02); // 打开相册

main_btn01.setOnClickListener(v -> {

// 打开相机

File outputImage = new File(getExternalCacheDir(), "shenhuiran_" + System.currentTimeMillis() + ".jpg"); // 名称（“shenhuiran_”+系统当前时间Millis（）

if (outputImage.exists()) outputImage.delete();

try {

outputImage.createNewFile();

} catch (IOException e) {

e.printStackTrace();

}

imageUri = FileProvider.getUriForFile(this, "com.example.camera.fileprovider", outputImage);

Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");

intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);

startActivityForResult(intent, TAKE_PHOTO);

});

main_btn02.setOnClickListener(v -> {

// 打开相册

// 在Activity Action里面有一个“ACTION_GET_CONTENT”字符串常量，

// 该常量让用户选择特定类型的数据，并返回该数据的URI.我们利用该常量，

// 然后设置类型为“image/*”，就可获得Android手机内的所有image。*/

Intent intent = new Intent("android.intent.action.GET_CONTENT");

intent.setType("image/*"); // 开启Pictures画面Type设定为image

// 打开相册

startActivityForResult(intent, CHOOSE_PHOTO);

});

}

/**

* 获取活动或片段的位图和图像路径onActivityResult

*

* @param requestCode

* @param resultCode

* @param data

*/

public static final int TAKE_PHOTO = 1;

public static final int CROP_PHOTO = 2;

public static final int CHOOSE_PHOTO = 3;

@Override

protected void onActivityResult(int requestCode, int resultCode, Intent data) {

super.onActivityResult(requestCode, resultCode, data);

switch (requestCode) {

case TAKE_PHOTO:

if (resultCode == Activity.RESULT_OK) {

try {

Bitmap bitmap = BitmapFactory.decodeStream(getContentResolver().openInputStream(imageUri));

main_img01.setImageBitmap(bitmap); // 展示刚拍过的照片

getImgBase64(main_img01); // 直接把 imageview 取出图片转换为base64格式

} catch (FileNotFoundException e) {

e.printStackTrace();

}

}

break;

case CROP_PHOTO:

if (resultCode == RESULT_OK) {

try {

Bitmap bitmap = BitmapFactory.decodeStream(getContentResolver().openInputStream(imageUri));

// 显示裁剪后的图片

main_img01.setImageBitmap(bitmap);

} catch (FileNotFoundException ex) {

ex.printStackTrace();

}

}

break;

case CHOOSE_PHOTO:

if (resultCode == RESULT_OK) {

handleImage(data);

}

break;

default:

break;

}

}

// 只在Android4.4及以上版本使用

@TargetApi(19)

private void handleImage(Intent data) {

String imagePath = null;

Uri uri = data.getData();

if (DocumentsContract.isDocumentUri(this, uri)) {

// 通过document id来处理

String docId = DocumentsContract.getDocumentId(uri);

if ("com.android.providers.media.documents".equals(uri.getAuthority())) {

// 解析出数字id

String id = docId.split(":")[1];

String selection = MediaStore.Images.Media._ID + "=" + id;

imagePath = getImagePath(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, selection);

} else if ("com.android.providers.downloads.documents".equals(uri.getAuthority())) {

Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"), Long.valueOf(docId));

imagePath = getImagePath(contentUri, null);

}

} else if ("content".equals(uri.getScheme())) {

// 如果不是document类型的Uri，则使用普通方式处理

imagePath = getImagePath(uri, null);

}

// 根据图片路径显示图片

displayImage(imagePath);

}

private String getImagePath(Uri uri, String selection) {

String path = null;

// 通过Uri和selection来获取真实图片路径

Cursor cursor = getContentResolver().query(uri, null, selection, null, null);

if (cursor != null) {

if (cursor.moveToFirst()) {

path = cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DATA));

}

cursor.close();

}

return path;

}

private void displayImage(String imagePath) {

if (imagePath != null) {

Bitmap bitmap = BitmapFactory.decodeFile(imagePath);

main_img01.setImageBitmap(bitmap);

} else {

Toast.makeText(this, "failed to get image", Toast.LENGTH_SHORT).show();

}

}

/**

* imageview取出图片转换为base64格式

*

* @param imageView

* @return

*/

private String takeimage;

public String getImgBase64(ImageView imageView) {

BitmapDrawable drawable = (BitmapDrawable) imageView.getDrawable();

Bitmap bitmap = drawable.getBitmap();

ByteArrayOutputStream bos = new ByteArrayOutputStream();

bitmap.compress(Bitmap.CompressFormat.PNG, 100, bos);

byte[] bb = bos.toByteArray();

takeimage = Base64.encodeToString(bb, Base64.NO_WRAP);

Log.d("111111 TakeActivity >>", "打印base64>>:" + takeimage);

// takeTv.setText("打印base64>>:" + image);

// jsJson.put("photographAdditionBase64", "data:image/png;base64," + takeimageview); // 图片上传，上传

return takeimage;

}

}