android - Toast 不显示 - Android

Question

我已经尝试了很多方法来显示我想要的 Toast(在 DrawView 类上)，以至于我真的不知道该在哪里运行了。

显然这很简单，但我遗漏了一些东西。我看过其他相关帖子，但没有成功。

有什么想法吗？

import android.app.Activity;
import android.os.Bundle;


public class MyActivity extends Activity{

    DrawView drawView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        drawView = new DrawView(this);
        setContentView(drawView);

    }

}

绘图 View 类:

import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;

import android.view.MotionEvent;
import android.view.View;
import android.widget.Toast;


public class DrawView extends View implements View.OnTouchListener{

    Paint paint = new Paint();

    public DrawView(MyActivity myActivity) {
        super(myActivity);

        setBackgroundColor(Color.WHITE);
        paint.setColor(Color.BLACK);

    }

    @Override
    protected void onDraw(Canvas canvas) {

        canvas.drawText("I'm text in a canvas!", 10, 10, paint);

    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {

        if(event.getAction() == MotionEvent.ACTION_DOWN){

            Toast.makeText(getContext(),"I'm a Toast!",Toast.LENGTH_SHORT).show();

        }

        return false;

    }

}

Answer 1

public class DrawView extends View  {

Paint paint = new Paint();
private Context context;

public DrawView(MainActivity context) {
    super(context);
    this.context = context;
    setBackgroundColor(Color.WHITE);
    paint.setColor(Color.BLACK);
}

@Override
protected void onDraw(Canvas canvas) {

    canvas.drawText("I'm text in a canvas!", 10, 10, paint);

}

@Override
public boolean onTouchEvent(MotionEvent event) {

    if (event.getAction() == MotionEvent.ACTION_DOWN) {

        Toast.makeText(context, "I'm a Toast!", Toast.LENGTH_SHORT).show();

    }

    return false;

}}