如何通过代码打开手机图库

Question

我想通过单击按钮打开手机图库。
在我的活动中，我有一个按钮，我想通过单击该按钮打开图库。

Answer 1

这是从应用程序打开图库的示例代码。

Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, "Select Picture"),SELECT_IMAGE);

OnActivityResult 用于获取图像。

public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == SELECT_IMAGE) {
        if (resultCode == Activity.RESULT_OK) {
            if (data != null) {
                try {
                    Bitmap bitmap = MediaStore.Images.Media.getBitmap(getActivity().getContentResolver(), data.getData());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        } else if (resultCode == Activity.RESULT_CANCELED)  {
            Toast.makeText(getActivity(), "Canceled", Toast.LENGTH_SHORT).show();
        }
    }
}

Answer 2

绑定您的按钮点击监听器：（这应该在您的 onCreate 方法中。）

ImageButton btn_choose_photo = (ImageButton) findViewById(R.id.add_photo_choose_photo); // Replace with id of your button.
btn_choose_photo.setOnClickListener(btnChoosePhotoPressed);

打开画廊：（这应该在您的活动课程中。）

public OnClickListener btnChoosePhotoPressed = new OnClickListener() {      
    @Override
    public void onClick(View v) {
        Intent i = new Intent(Intent.ACTION_PICK,
                   android.provider.MediaStore.Images.Media.INTERNAL_CONTENT_URI);
        final int ACTIVITY_SELECT_IMAGE = 1234;
        startActivityForResult(i, ACTIVITY_SELECT_IMAGE); 
    }
};

要获得选择的图像：（这应该在您的活动类中。）

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

    switch(requestCode) { 
    case 1234:
        if(resultCode == RESULT_OK){  
            Uri selectedImage = data.getData();
            String[] filePathColumn = {MediaStore.Images.Media.DATA};

            Cursor cursor = getContentResolver().query(selectedImage, filePathColumn, null, null, null);
            cursor.moveToFirst();

            int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
            String filePath = cursor.getString(columnIndex);
            cursor.close();


            Bitmap yourSelectedImage = BitmapFactory.decodeFile(filePath);
            /* Now you have choosen image in Bitmap format in object "yourSelectedImage". You can use it in way you want! */
        }
    }

};

Answer 3

在按钮的 OnClickListener 上，创建此意图：

Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(
                  "content://media/internal/images/media"));

这符合您的期望吗？

Answer 4

试试这个例子，我可以通过单击按钮打开我的画廊，我相信这对你有用

public class MainActivity extends Activity {

    private static final int SELECT_PICTURE = 1;

    private String selectedImagePath;
    private ImageView img;

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        img = (ImageView)findViewById(R.id.imageView1);

        ((Button) findViewById(R.id.button1))
                .setOnClickListener(new OnClickListener() {
                    public void onClick(View arg0) {
                        Intent intent = new Intent();
                        intent.setType("image/*");
                        intent.setAction(Intent.ACTION_GET_CONTENT);
                        startActivityForResult(Intent.createChooser(intent,"Select Picture"), SELECT_PICTURE);
                    }
                });
    }

    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (resultCode == RESULT_OK) {
            if (requestCode == SELECT_PICTURE) {
                Uri selectedImageUri = data.getData();
                selectedImagePath = getPath(selectedImageUri);
                System.out.println("Image Path : " + selectedImagePath);
                img.setImageURI(selectedImageUri);
            }
        }
    }

    public String getPath(Uri uri) {
        String[] projection = { MediaStore.Images.Media.DATA };
        Cursor cursor = managedQuery(uri, projection, null, null, null);
        int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
        cursor.moveToFirst();
        return cursor.getString(column_index);
    }
}

这是你的 main.xml 应该是这样的

<?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"
    >
<TextView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="@string/hello"
    />
<Button android:text="Browse gallery"
    android:id="@+id/button1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content">
</Button>
<ImageView android:id="@+id/imageView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content">
</ImageView>
</LinearLayout>

同样在 MainActivity.java 中，添加所有这些导入

import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;

应用这个例子，你就完成了:)

Answer 5

更新：

根据documentation activityForResult 从 api 级别 30 开始已弃用

你必须使用registerForActivityResult

 private lateinit var launcher: ActivityResultLauncher<String>
   ...
 // NOTE YOU SHOULD REGISTER IN `onAttach ()` or IN `onCreate()` callbacks.
 override fun onAttach(context: Context) {
    super.onAttach(context)
   ...

    launcher = registerForActivityResult(ActivityResultContracts.GetContent()) {
        //.. your picked image result here
    }

然后这样称呼它：

 launcher.launch("image/*")