首先我们看布局代码的文件：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<Button
android:id="@+id/bu_1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Take Photo"/>
<Button
android:id="@+id/choose_from_album"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="chose from Album"/>
<ImageView
android:id="@+id/picture"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"/>
</LinearLayout>
图中有两个按钮,一个是用来启动照相机的,另一个是用来选择本地照片的,还有一个ImageView控件,是用来显示照片的
然后就是主函数中的代码：
package com.example.pc_ly.cameraalbumtest;
import android.Manifest;
import android.annotation.TargetApi;
import android.content.ContentUris;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Build;
import android.provider.DocumentsContract;
import android.provider.MediaStore;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v4.content.FileProvider;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.concurrent.Callable;
import static android.R.attr.handle;
public class MainActivity extends AppCompatActivity {
public static final int TAKE_PHOTO=1;
public static final int CHOOSE_PHOTO=2;
private ImageView picture;
private Uri imageUri;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button button=(Button)findViewById(R.id.bu_1);
picture=(ImageView)findViewById(R.id.picture);
Button choose=(Button)findViewById(R.id.choose_from_album);
choose.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {//确认是否有权限开启
if(ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE)!= PackageManager.PERMISSION_GRANTED){
ActivityCompat.requestPermissions(MainActivity.this,new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},1);
}
else{
openAlbum();
}
}
});
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
File outputImage=new File(getExternalCacheDir(),"output_image.jpg");//用于存放摄像头拍摄的照片
try{
if (outputImage.exists()){
outputImage.delete();
}
outputImage.createNewFile();
}catch (IOException e){
e.printStackTrace();
}
if (Build.VERSION.SDK_INT>=24){//根据android的版本对URI执行操作
imageUri= FileProvider.getUriForFile(MainActivity.this,"com.example.pc_ly.cameraalbumtest.fileprovider",outputImage);}
else{imageUri=Uri.fromFile(outputImage);
}
Intent intent=new Intent("android.media.action.IMAGE_CAPTURE");//系统会找到能够找到能响应这个intent程序去执行
intent.putExtra(MediaStore.EXTRA_OUTPUT,imageUri);
startActivityForResult(intent,TAKE_PHOTO);
}
});
}
@Override
protected void onActivityResult(int requestCode,int resultCode,Intent data){//如果拍照成功，则会将照片显示在容器中
switch (requestCode){
case TAKE_PHOTO:
if(resultCode==RESULT_OK){
try{
Bitmap bitmap= BitmapFactory.decodeStream(getContentResolver().openInputStream(imageUri));
picture.setImageBitmap(bitmap);
}catch (FileNotFoundException e){
e.printStackTrace();
}
}
break;
case CHOOSE_PHOTO:
if(resultCode==RESULT_OK){
//判断手机版本号
if(Build.VERSION.SDK_INT>=19){
handleImageOnKitKat(data);
}
else{
handleImageBeforeKitKat(data);
}
}
default:
break;
}
}
public void openAlbum(){
Intent intent=new Intent("android.intent.action.GET_CONTENT");
intent.setType("image/*");
startActivityForResult(intent,CHOOSE_PHOTO);//打开相册
}
public void onRequestPermissionResult(int requestCode,String[] permissions,int[] grantResults){//看是否权限已经打开
switch (requestCode){
case 1:
if(grantResults.length>0&&grantResults[0]==PackageManager.PERMISSION_GRANTED){
openAlbum();
}
else{
Toast.makeText(this,"You denied the permission",Toast.LENGTH_SHORT).show();
}
break;
default:
}
}
@TargetApi(19)
private void handleImageOnKitKat(Intent data){//根据版本对uri进行解析
String imagePath=null;
Uri uri=data.getData();
if(DocumentsContract.isDocumentUri(this,uri)){
//如果是document类型的Uri，则通过document id处理
String docId=DocumentsContract.getDocumentId(uri);
if("com.android.providers.media.documents".equals(uri.getAuthority())){
String id=docId.split(":")[1];//解析出数字格式的id
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".equalsIgnoreCase(uri.getScheme())){
imagePath=getImagePath(uri,null);
}
else if("file".equalsIgnoreCase(uri.getScheme())){
imagePath=uri.getPath();
}
}
}
private void handleImageBeforeKitKat(Intent data){//老版本的解析
Uri uri=data.getData();
String imagePath=getImagePath(uri,null);
displayImage(imagePath);
}
private String getImagePath(Uri uri,String selection){//获取路径
String path=null;
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){//展示照片
if(imagePath!=null){
Bitmap bitmap=BitmapFactory.decodeFile(imagePath);
picture.setImageBitmap(bitmap);
}
else{
Toast.makeText(this,"faild to get image",Toast.LENGTH_SHORT).show();
}
}
}
最后还有一个要注意一个重要的东西, 要申明一下权限, 如下图：
上面的注释已经写得很清楚了啦,我就不一一解释了，下面来看效果图：
运行之后是这个界面，然后我们点击take photo按钮,就可以打开照相机啦,如下图：
然后我们点击CHOSE FROM ALBUM按钮,就可以选择照片文件啦：
好啦,这次就到这里啦，有什么疑问的话欢迎和我留言呀
其他博客的链接：
欢迎各位访问哦，这次就到这里啦！