Question

我希望在同一个布局上有两个按钮，您单击第一个按钮，选择一个图像，该按钮将更改为所选的图像。单击第二个按钮，选择的图像将替换按钮。最容易使用imageButton而不是ImageView。如果可能，我想要代码，谢谢。

（还是不明白？结尾应该是用户选择的彼此相邻的2张图片。）

MainActivity：

package com.example.triptych;

import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.provider.MediaStore;
import android.view.View;
import android.widget.ImageButton;
import android.widget.Toast;

public class MainActivity extends Activity {
    private static int RESULT_LOAD_IMG = 1;
    String imgDecodableString;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    public void loadImagefromGallery(View view) {
        // Create intent to Open Image applications like Gallery, Google Photos
        Intent galleryIntent = new Intent(Intent.ACTION_PICK,
                android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
        // Start the Intent
        startActivityForResult(galleryIntent, RESULT_LOAD_IMG);
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        try {
            // When an Image is picked
            if (requestCode == RESULT_LOAD_IMG && resultCode == RESULT_OK
                    && null != data) {
                // Get the Image from data

                Uri selectedImage = data.getData();
                String[] filePathColumn = { MediaStore.Images.Media.DATA };

                // Get the cursor
                Cursor cursor = getContentResolver().query(selectedImage,
                        filePathColumn, null, null, null);
                // Move to first row
                cursor.moveToFirst();

                int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
                imgDecodableString = cursor.getString(columnIndex);
                cursor.close();
                ImageButton imageButton = (ImageButton) findViewById(R.id.buttonLoadPicture);
                // Set the Image in ImageView after decoding the String
                imageButton.setImageBitmap(BitmapFactory
                        .decodeFile(imgDecodableString));

            } else {
                Toast.makeText(this, "You haven't picked Image",
                        Toast.LENGTH_LONG).show();
            }
        } catch (Exception e) {
            Toast.makeText(this, "Something went wrong", Toast.LENGTH_LONG)
                    .show();
        }

    }

}

activity_main.xml中：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <ImageButton
        android:id="@+id/buttonLoadPicture"
        android:layout_width="160dp"
        android:layout_height="300dp"
        android:layout_marginLeft="10dp"
        android:layout_weight="0.51"
        android:contentDescription="TODO"
        android:onClick="loadImagefromGallery"
        android:src="@drawable/ic_launcher"
        android:text="@string/load_picture" />

    <ImageButton
        android:id="@+id/button2"
        android:layout_width="160dp"
        android:layout_height="300dp"
        android:layout_marginLeft="180dp"
        android:layout_weight="0.51"
        android:contentDescription="TODO"
        android:onClick="loadImagefromGallery"
        android:src="@drawable/ic_launcher"
        android:text="@string/load_picture" />

</RelativeLayout>

另一个问题，我是否为第二个按钮创建另一个活动并粘贴相同的代码或者我是否在同一个活动上执行此操作？

Answer 1

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
  <ImageButton
    android:id="@+id/buttonLoadPicture"
    android:layout_width="160dp"
    android:layout_height="300dp"
    android:layout_marginLeft="10dp"
    android:layout_weight="0.51"
    android:contentDescription="TODO"
    android:onClick="loadImagefromGallery"
    android:src="@drawable/ic_launcher"
    android:text="@string/load_picture" />

<ImageButton
    android:id="@+id/button2"
    android:layout_width="160dp"
    android:layout_height="300dp"
    android:layout_marginLeft="180dp"
    android:layout_weight="0.51"
    android:contentDescription="TODO"
    android:onClick="loadImagefromGallery"
    android:src="@drawable/ic_launcher"
    android:text="@string/load_picture" />

Answer 2

您可以尝试这样的事情：

在 MainActivity 类中，您需要创建2种不同的方法来处理图库选择图像，并在点击两个不同的图像时调用它按钮，见下面的代码：您的 MainActivity.jav a将如下所示：

public class MainActivity extends ActionBarActivity {
    private static int RESULT_LOAD_IMG = 1, RESULT_LOAD_IMG_TWO = 2;
    String imgDecodableString, imgDecodableStringTwo;
    ImageButton btn_load, btn_loadTwo;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        btn_load = (ImageButton) findViewById(R.id.buttonLoadPicture);
        btn_loadTwo = (ImageButton) findViewById(R.id.buttonLoad);
        btn_loadTwo.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                loadImagefromGalleryTwo(btn_loadTwo);
            }
        });
        btn_load.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                loadImagefromGallery(btn_load);
            }
        });
    }

    public void loadImagefromGallery(View view) {
        Intent galleryIntent = new Intent(Intent.ACTION_PICK,
                android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
        startActivityForResult(galleryIntent, RESULT_LOAD_IMG);
    }

    public void loadImagefromGalleryTwo(View view) {
        Intent galleryIntent = new Intent(Intent.ACTION_PICK,
                android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
        startActivityForResult(galleryIntent, RESULT_LOAD_IMG_TWO);
    }

    @SuppressLint("NewApi")
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        try {
            if (requestCode == RESULT_LOAD_IMG && resultCode == RESULT_OK && null != data) {

                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]);
                imgDecodableString = cursor.getString(columnIndex);
                cursor.close();

                Drawable d = new BitmapDrawable(getResources(), BitmapFactory.decodeFile(imgDecodableString));
                btn_load.setBackground(d);

            } else if (requestCode == RESULT_LOAD_IMG_TWO && resultCode == RESULT_OK && null != data) {
                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]);
                imgDecodableStringTwo = cursor.getString(columnIndex);
                cursor.close();

                Drawable d = new BitmapDrawable(getResources(), BitmapFactory.decodeFile(imgDecodableStringTwo));
                btn_loadTwo.setBackground(d);
            }
        } catch (Exception e) {
            Toast.makeText(this, "Something went wrong", Toast.LENGTH_LONG).show();
        }

    }
}

输出： enter image description here

希望它有所帮助！

Answer 3

不应从UI线程调用getContentResolver（）。查询

将图库中的图像加载到ImageButton中（视图）

3 个答案: