Java 在imageview android中捕获图像的中心绘制一个圆

我必须在图像视图中拍摄的图像的中心画一个圆圈，并保存在DB中。首先捕获图像并裁剪图像，在图像中心画圆，显示在图像视图中，并保存在DB中。圆圈不是画出来的。我尝试了很多方法。请帮帮我

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center_horizontal"
    android:orientation="vertical"
    android:baselineAligned="false"
    tools:context=".MainActivity"
    android:weightSum="1">

    <Button
        android:id="@+id/btn_select_image"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dp"
        android:layout_marginRight="10dp"
        android:layout_marginTop="10dp"
        android:text="Select Image" />


    <LinearLayout
        android:layout_width="226dp"
        android:layout_height="231dp"
        android:orientation="vertical"
        android:weightSum="1">

        <ImageView
            android:id="@+id/img_photo"
            android:layout_width="200dp"
            android:layout_height="500dp"
            android:layout_marginTop="10dp"
            android:scaleType="fitXY"
            android:layout_weight="0.45" />
    </LinearLayout>

    <LinearLayout
        android:layout_width="280dp"
        android:layout_height="77dp"
        android:gravity="center_vertical|center_horizontal"
        android:orientation="horizontal">

        <TextView
            android:id="@+id/xPos"
            android:layout_width="5dp"
            android:layout_height="wrap_content"
            android:layout_weight="0.32"
            android:gravity="left|center_vertical"
            android:padding="5dip"
            android:visibility="invisible" />

        <TextView
            android:id="@+id/yPos"
            android:layout_width="5dp"
            android:layout_height="wrap_content"
            android:layout_weight="0.32"
            android:gravity="right|center_vertical"
            android:padding="5dip"
            android:visibility="invisible" />
    </LinearLayout>


</LinearLayout>

cropingoptionadapter.java

package knuckle.app.com.knuckleauthentication;

import java.util.ArrayList;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;
import knuckle.app.com.knuckleauthentication.R;
import android.support.v7.app.AppCompatActivity;


public class CropingOptionAdapter extends ArrayAdapter {
    private ArrayList mOptions;
    private LayoutInflater mInflater;

    public CropingOptionAdapter(Context context, ArrayList options) {
        super(context, R.layout.croping_selector, options);

        mOptions  = options;

        mInflater = LayoutInflater.from(context);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup group) {
        if (convertView == null)
            convertView = mInflater.inflate(R.layout.croping_selector, null);

        CropingOption item = (CropingOption) mOptions.get(position);

        if (item != null) {
            ((ImageView) convertView.findViewById(R.id.img_icon)).setImageDrawable(item.icon);
            ((TextView) convertView.findViewById(R.id.txt_name)).setText(item.title);

            return convertView;
        }

        return null;
    }
}

Datahelper.java

package knuckle.app.com.knuckleauthentication;

import java.io.ByteArrayOutputStream;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.util.Log;

public class DataHelper extends SQLiteOpenHelper {
    public static final String DATABASE_NAME = "knuckledb";
    public static final String TABLE_NAME = "tbl_knuckle_img";
    public static final int DATABASE_VERSION = 1;
    public static final String CREATE_TABLE = "CREATE TABLE IF NOT EXISTS " + TABLE_NAME + "(id INTEGER PRIMARY KEY AUTOINCREMENT, img BLOB NOT NULL, description TEXT NULL)";
    public static final String DELETE_TABLE = "DROP TABLE IF EXISTS " + TABLE_NAME;

    public DataHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);

    }

    public void onCreate(SQLiteDatabase db) {
        // Create the table
        db.execSQL(CREATE_TABLE);

    }

    //Upgrading database
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        //Drop older table if existed
        db.execSQL(DELETE_TABLE);
        //Create tables again
        onCreate(db);
    }

    public void insertBitmap(Bitmap bm) {

        // Convert the image into byte array
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        bm.compress(Bitmap.CompressFormat.PNG, 100, out);
        byte[] buffer = out.toByteArray();
        // Open the database for writing
        SQLiteDatabase db = this.getWritableDatabase();
        // Start the transaction.
        db.beginTransaction();
        ContentValues values;
        int width=bm.getWidth();
        int height=bm.getHeight();

        int centerX=width/2;
        int centerY=height/2;

        try {
            values = new ContentValues();
            values.put("img", buffer);
            values.put("description", "knuckle image");
            values.put("centerX", centerX);
            values.put("centerY", centerY);
            // Insert Row
            long i = db.insert(TABLE_NAME, null, values);
            Log.i("Insert", i + "");
            // Insert into database successfully.
            db.setTransactionSuccessful();

        } catch (SQLiteException e) {
            e.printStackTrace();

        } finally {
            db.endTransaction();
            // End the transaction.
            db.close();
            // Close database
        }
    }

    public Bitmap getBitmap(int id) {
        Bitmap bitmap = null;
        // Open the database for reading
        SQLiteDatabase db = this.getReadableDatabase();
        // Start the transaction.
        db.beginTransaction();

        try {
            String selectQuery = "SELECT * FROM " + TABLE_NAME + " WHERE id = " + id;
            Cursor cursor = db.rawQuery(selectQuery, null);
            if (cursor.getCount() > 0) {
                while (cursor.moveToNext()) {
                    // Convert blob data to byte array
                    byte[] blob = cursor.getBlob(cursor.getColumnIndex("img"));
                    // Convert the byte array to Bitmap
                    bitmap = BitmapFactory.decodeByteArray(blob, 0, blob.length);

                }

            }
            db.setTransactionSuccessful();

        } catch (SQLiteException e) {
            e.printStackTrace();

        } finally {
            db.endTransaction();
            // End the transaction.
            db.close();
            // Close database
        }
        return bitmap;

    }

}

---

你想在这个链接中画这样的图像吗

[绘制圆形图像]

---

您可以在应用程序中使用文件RoundedImageView.java，并在XMl布局中使用它，而不是在ImageView中使用它。

否。只需在捕获图像的中心添加一个圆圈即可

package knuckle.app.com.knuckleauthentication;

import java.util.ArrayList;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;
import knuckle.app.com.knuckleauthentication.R;
import android.support.v7.app.AppCompatActivity;


public class CropingOptionAdapter extends ArrayAdapter {
    private ArrayList mOptions;
    private LayoutInflater mInflater;

    public CropingOptionAdapter(Context context, ArrayList options) {
        super(context, R.layout.croping_selector, options);

        mOptions  = options;

        mInflater = LayoutInflater.from(context);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup group) {
        if (convertView == null)
            convertView = mInflater.inflate(R.layout.croping_selector, null);

        CropingOption item = (CropingOption) mOptions.get(position);

        if (item != null) {
            ((ImageView) convertView.findViewById(R.id.img_icon)).setImageDrawable(item.icon);
            ((TextView) convertView.findViewById(R.id.txt_name)).setText(item.title);

            return convertView;
        }

        return null;
    }
}

package knuckle.app.com.knuckleauthentication;

import java.io.ByteArrayOutputStream;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.util.Log;

public class DataHelper extends SQLiteOpenHelper {
    public static final String DATABASE_NAME = "knuckledb";
    public static final String TABLE_NAME = "tbl_knuckle_img";
    public static final int DATABASE_VERSION = 1;
    public static final String CREATE_TABLE = "CREATE TABLE IF NOT EXISTS " + TABLE_NAME + "(id INTEGER PRIMARY KEY AUTOINCREMENT, img BLOB NOT NULL, description TEXT NULL)";
    public static final String DELETE_TABLE = "DROP TABLE IF EXISTS " + TABLE_NAME;

    public DataHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);

    }

    public void onCreate(SQLiteDatabase db) {
        // Create the table
        db.execSQL(CREATE_TABLE);

    }

    //Upgrading database
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        //Drop older table if existed
        db.execSQL(DELETE_TABLE);
        //Create tables again
        onCreate(db);
    }

    public void insertBitmap(Bitmap bm) {

        // Convert the image into byte array
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        bm.compress(Bitmap.CompressFormat.PNG, 100, out);
        byte[] buffer = out.toByteArray();
        // Open the database for writing
        SQLiteDatabase db = this.getWritableDatabase();
        // Start the transaction.
        db.beginTransaction();
        ContentValues values;
        int width=bm.getWidth();
        int height=bm.getHeight();

        int centerX=width/2;
        int centerY=height/2;

        try {
            values = new ContentValues();
            values.put("img", buffer);
            values.put("description", "knuckle image");
            values.put("centerX", centerX);
            values.put("centerY", centerY);
            // Insert Row
            long i = db.insert(TABLE_NAME, null, values);
            Log.i("Insert", i + "");
            // Insert into database successfully.
            db.setTransactionSuccessful();

        } catch (SQLiteException e) {
            e.printStackTrace();

        } finally {
            db.endTransaction();
            // End the transaction.
            db.close();
            // Close database
        }
    }

    public Bitmap getBitmap(int id) {
        Bitmap bitmap = null;
        // Open the database for reading
        SQLiteDatabase db = this.getReadableDatabase();
        // Start the transaction.
        db.beginTransaction();

        try {
            String selectQuery = "SELECT * FROM " + TABLE_NAME + " WHERE id = " + id;
            Cursor cursor = db.rawQuery(selectQuery, null);
            if (cursor.getCount() > 0) {
                while (cursor.moveToNext()) {
                    // Convert blob data to byte array
                    byte[] blob = cursor.getBlob(cursor.getColumnIndex("img"));
                    // Convert the byte array to Bitmap
                    bitmap = BitmapFactory.decodeByteArray(blob, 0, blob.length);

                }

            }
            db.setTransactionSuccessful();

        } catch (SQLiteException e) {
            e.printStackTrace();

        } finally {
            db.endTransaction();
            // End the transaction.
            db.close();
            // Close database
        }
        return bitmap;

    }

}