java之查找 ImageView 错误中像素的颜色_编程设计

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4年前关闭。

我的程序当前显示在图像 View 中拍摄的图像，我已经编码了一个部分，当您在图像 View 上的某处触摸时，它应该找到该点的颜色并通过将TextView更改为该颜色来显示该颜色。但是，当我触摸屏幕时，应用程序崩溃并关闭。
某些代码不执行任何atm操作，例如稍后要使用的SeekBar。
代码方面的任何改进以及如何改进完成任务的方式，请告诉我，因为我是Java新手。

Activity :

import android.app.Activity; 
import android.content.Intent; 
import android.graphics.Bitmap; 
import android.graphics.BitmapFactory; 
import android.graphics.Color; 
import android.graphics.Matrix; 
import android.graphics.drawable.BitmapDrawable; 
import android.graphics.drawable.Drawable; 
import android.net.Uri; 
import android.os.Bundle; 
import android.os.Environment; 
import android.provider.MediaStore; 
import android.view.MotionEvent; 
import android.view.View; 
import android.widget.Button; 
import android.widget.CompoundButton; 
import android.widget.ImageView; 
import android.widget.SeekBar; 
import android.widget.TextView; 
import android.widget.ToggleButton; 
 
 
import java.io.File; 
 
public class MainActivity extends Activity { 
 
    private static final int CONTENT_REQUEST = 1337; 
    private File output = null; 
    Button button; 
    ToggleButton Edit; 
    Button Finalise; 
    ImageView imageView; 
    Button ButtonState; 
    SeekBar SeekBarState; 
    SeekBar seekBar; 
    Bitmap bitmap; 
    Bitmap bitmap2; 
    TextView textView; 
 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
        super.onCreate(savedInstanceState); 
        setContentView(R.layout.activity_main); 
 
        button = (Button) findViewById(R.id.CameraButton); 
        Edit = (ToggleButton) findViewById(R.id.EditorButton); 
        Finalise = (Button) findViewById(R.id.FinaliseButton); 
        seekBar = (SeekBar) findViewById(R.id.seekBar); 
        imageView = (ImageView) findViewById(R.id.Image_view); 
        ButtonState = (ToggleButton) findViewById(R.id.EditorButton); 
        ButtonState = (Button) findViewById(R.id.FinaliseButton); 
        SeekBarState = (SeekBar) findViewById(R.id.seekBar); 
 
        ButtonState.setEnabled(false); 
        SeekBarState.setVisibility(View.GONE); 
 
 
        button.setOnClickListener(new View.OnClickListener() { 
 
            public void onClick(View v) { 
 
 
                Intent i = new Intent(MediaStore.ACTION_IMAGE_CAPTURE); 
                File dir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM + "/COMP4"); //Storage/sdcard0/DCIM/COMP4/ 
                dir.mkdirs(); 
                output = new File(dir, "COMP4Image.jpeg"); 
                i.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(output)); 
                startActivityForResult(i, CONTENT_REQUEST); 
 
 
            } 
 
 
        }); 
 
 
        Edit.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { 
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { 
                if (isChecked) { 
                    SeekBarState = (SeekBar) findViewById(R.id.seekBar); 
                    SeekBarState.setVisibility(View.VISIBLE); 
 
                } else { 
 
                    SeekBarState = (SeekBar) findViewById(R.id.seekBar); 
                    SeekBarState.setVisibility(View.GONE); 
 
                } 
            } 
        }); 
 
 
    } 
 
 
 
 
    @Override 
    protected void onActivityResult(int requestCode, int resultCode, Intent data) { 
        ButtonState = (Button) findViewById(R.id.CameraButton); 
        ButtonState.setEnabled(false); 
        ButtonState = (Button) findViewById(R.id.EditorButton); 
        ButtonState.setEnabled(true); 
        ButtonState = (Button) findViewById(R.id.FinaliseButton); 
        ButtonState.setEnabled(true); 
 
        BitmapFactory.Options bmOptions = new BitmapFactory.Options(); 
        Bitmap bitmap = BitmapFactory.decodeFile(output.getAbsolutePath(), bmOptions); 
        imageView.setScaleType(ImageView.ScaleType.CENTER_INSIDE); 
        imageView.setImageBitmap(bitmap); 
 
        final Bitmap bitmap2 = ((BitmapDrawable) imageView.getDrawable()).getBitmap(); 
        imageView.setOnTouchListener(new View.OnTouchListener() { 
            @Override 
            public boolean onTouch(View v, MotionEvent event) { 
                int x = (int) event.getX(); 
                int y = (int) event.getY(); 
                int pixel = bitmap2.getPixel(x, y); 
 
 
                int red = Color.red(pixel); 
                int blue = Color.blue(pixel); 
                int green = Color.green(pixel); 
                textView.setTextColor(Color.rgb(red, green, blue)); 
                return false; 
 
 
            } 
        }); 
 
 
    } 
 
 
    }

版式:

<Button 
    android:layout_width="400dp" 
    android:layout_height="50dp" 
    android:text="Capture Image" 
    android:id="@+id/CameraButton" 
    android:onClick="buttonOnClick" 
    android:layout_alignParentTop="true" 
    android:textStyle="bold" 
    android:layout_marginRight="380dp" 
    android:layout_marginEnd="380dp" 
    android:layout_alignRight="@+id/Image_view" 
    android:layout_alignEnd="@+id/Image_view" /> 
 
<ImageView 
    android:layout_width="1000dp" 
    android:layout_height="1000dp" 
    android:id="@+id/Image_view" 
    android:contentDescription="@string/image_cd_camera" 
    android:layout_centerHorizontal="true" 
    android:layout_marginTop="50dp" 
    android:layout_marginBottom="0dp"/> 
 
<Button 
    android:layout_width="400dp" 
    android:layout_height="50dp" 
    android:text="Finalise" 
    android:id="@+id/FinaliseButton" 
    android:onClick="FinaliseOnClick" 
    android:textStyle="bold" 
    android:layout_marginLeft="380dp" 
    android:layout_marginStart="380dp" 
    android:layout_alignParentTop="true" 
    android:layout_centerHorizontal="true" /> 
 
<SeekBar 
    android:layout_width="500dp" 
    android:layout_height="wrap_content" 
    android:id="@+id/seekBar" 
    android:layout_alignBottom="@+id/Image_view" 
    android:layout_marginBottom="10dp" 
    android:layout_centerHorizontal="true" 
    android:max="510" 
    android:progress="255"/> 
 
<ToggleButton 
    android:layout_width="400dp" 
    android:layout_height="50dp" 
    android:text="Edit Image" 
    android:id="@+id/EditorButton" 
    android:layout_alignTop="@+id/FinaliseButton" 
    android:layout_toRightOf="@+id/FinaliseButton" 
    android:layout_toEndOf="@+id/FinaliseButton" 
    android:textStyle="bold" /> 
 
<TextView 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:textAppearance="?android:attr/textAppearanceLarge" 
    android:text="TESTING COLOURS" 
    android:id="@+id/textView" 
    android:textSize="50dp" 
    android:layout_centerVertical="true" 
    android:layout_above="@id/seekBar" 
     />

请您参考如下方法:

用:

ToggleButton Edit; --> ToggleButton edit; 
Button Finalise; Button ButtonState; --> Button finalise, buttonState;      
SeekBar SeekBarState; --> SeekBar seekBarState;

关于java - 查找 ImageView 错误中像素的颜色，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/35301831/

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