在GridView单元格上绘制线-Android

到目前为止，这就是我的代码。为了在此时包含图像的单元格上画一条线，我想我知道我需要使用绘画或路径哪个？。在其中，我将声明起始点是什么，然后当用户触摸屏幕的另一部分时，这将是第二个点。欢迎提出任何建议。我真的，真的是新手，所以非常感谢您的帮助。谢谢。

您可以重写onDraw方法以在视图中执行自定义绘图。有关详细信息，请参阅

package com.hh.LetterGame;

import android.app.Activity;
import android.graphics.Canvas;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.GridView;
import android.widget.Toast;

public class MainActivity extends Activity {


    //This is what is first displayed when the person opens the app:
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        //Displays the letters on the board.
            GridView gridview = (GridView) findViewById(R.id.letters);
        gridview.setAdapter(new letterImageAdapter(this));

        //Controls what is displayed when the user clicks on the letter.
        gridview.setOnItemClickListener(new OnItemClickListener() {
            public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
                Toast.makeText(MainActivity.this, "" + position, Toast.LENGTH_SHORT).show();

            }
        });

        //Displays the header, including players and word selected.
        //NOT FINISHED: Needs to show player pictures and also the word the player is making.
        GridView header = (GridView) findViewById(R.id.header);


    }

    //Draw lines between the letters.

    //Menu options within the app.
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

}