Android 从ExternalMediaDirs在GridView中显示图像

这个应用程序捕获图像并将其存储在/storage/simulated/0/Android/media/com.example.camerapp/中，我想在GridView中显示它们

首先，我在activity_display.xml中创建了gridview，在DisplayActivity中设置了adapter，并实现了ImageAdapter.java，首先我使用图标表单drawable在girdview中显示，但我不确定如何从存储图像的位置传递图像

如何将可绘制图像替换为外部图像

activty_display.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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=".DisplayActivity">

    <GridView
        android:id="@+id/grid_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:numColumns="2"
        android:horizontalSpacing="10dp"
        android:verticalSpacing="10dp"
        android:gravity="center"
        android:stretchMode="columnWidth"
        tools:layout_editor_absoluteX="1dp"
        tools:layout_editor_absoluteY="1dp" />
</androidx.constraintlayout.widget.ConstraintLayout>

ImageAdapter.java

package com.example.cameraapp;

import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;


public class ImageAdapter extends BaseAdapter {

    private Context mContext;

    File mFile = new File("/storage/emulated/0/Android/media/com.example.cameraapp/one.jpg");
    Uri mUri = Uri.fromFile(mFile);

    public Uri[] uriArray = {
        mUri, mUri, mUri
    };

    public int[] imageArray = {
            R.drawable.and_icon,
            R.drawable.and_icon, R.drawable.and_icon,
            R.drawable.and_icon, R.drawable.and_icon,
            R.drawable.and_icon, R.drawable.and_icon,
            R.drawable.and_icon, R.drawable.and_icon,
    };

    public ImageAdapter(Context mContext) {
        this.mContext = mContext;
    }

    @Override
    public int getCount() {
        return imageArray.length;
    }

    @Override
    public Object getItem(int position) {
        return imageArray[position];
    }

    @Override
    public long getItemId(int position) {
        return 0;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ImageView imageView = new ImageView(mContext);
        // imageView.setImageResource(imageArray[position]);

        Bitmap mBitmap = BitmapFactory.decodeFile(mFile.getAbsolutePath());

        //imageView.setImageURI(uriArray[position]);
        imageView.setImageBitmap(mBitmap);
        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        imageView.setLayoutParams(new GridView.LayoutParams(600, 350));

        return imageView;
    }
}

---

imageView.setImageResource（imageArray[position]）您将不会从资源加载，因此请删除该行。替换为类似
imageView.setImageUri（uriArray[position]）。uri来自目录的File.list（），它们看起来像
file:///storage/emulated/0/Android/media/com.example.camerapp/mypicture.jpg
。但是将原始图像（分辨率高）放在gridview中不是一个好主意。在你完成这项工作后，你的第二个任务是将它们调整到更小的分辨率。我试着按照你说的做，如下所示，我正在显示一个仅此一个的图像来测试，但我得到了一个绑定错误的数组。在此之后，我将使用缩略图而不是完整的图像File mFile=新文件（“/storage/emulated/0/Android/media/com.example.camerapp/one.jpg”）；Uri mUri=Uri.fromFile（mFile）；公共Uri[]urirray={mUri，mUri，mUri}```把所有代码放在你的帖子里。不在评论中。并发布完整的代码和完整的日志。我更新了帖子，活动打开了，但当我试图滚动时，它崩溃了。
package com.example.cameraapp;

import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;


public class ImageAdapter extends BaseAdapter {

    private Context mContext;

    File mFile = new File("/storage/emulated/0/Android/media/com.example.cameraapp/one.jpg");
    Uri mUri = Uri.fromFile(mFile);

    public Uri[] uriArray = {
        mUri, mUri, mUri
    };

    public int[] imageArray = {
            R.drawable.and_icon,
            R.drawable.and_icon, R.drawable.and_icon,
            R.drawable.and_icon, R.drawable.and_icon,
            R.drawable.and_icon, R.drawable.and_icon,
            R.drawable.and_icon, R.drawable.and_icon,
    };

    public ImageAdapter(Context mContext) {
        this.mContext = mContext;
    }

    @Override
    public int getCount() {
        return imageArray.length;
    }

    @Override
    public Object getItem(int position) {
        return imageArray[position];
    }

    @Override
    public long getItemId(int position) {
        return 0;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ImageView imageView = new ImageView(mContext);
        // imageView.setImageResource(imageArray[position]);

        Bitmap mBitmap = BitmapFactory.decodeFile(mFile.getAbsolutePath());

        //imageView.setImageURI(uriArray[position]);
        imageView.setImageBitmap(mBitmap);
        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        imageView.setLayoutParams(new GridView.LayoutParams(600, 350));

        return imageView;
    }
}